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123 W. Spruce St., Missoula, MT 59802
www.dcengineering.net
August 13, 2012
Salmon School District
900 Sharkey Street
Salmon, ID 83467
Structural Observation and Seismic Evaluation
Pioneer Elementary School
907 Sharkey Street
Salmon, ID 83467
EXECUTIVE SUMMARY
DC Engineering Job No:
Date of Visual Observation:
Attendees:
12SAL01
July 10, 2012
Joe Lane, DC Engineering
Ken Armstrong, Salmon School District
Standards:
• 2009 International Building Code
• 2009 International Existing Building Code
• ASCE/SEI 7-05 Minimum Design Loads for Buildings and Other Structures
• Idaho General Safety and Health Standards 2006 Rev-3
• ASCE/SEI 31-03 Seismic Evaluation of Existing Building
Historical Building:
No
Emergency Earthquake Shelter:
No
Level of Seismicity:
High
Performance Level:
Life Safety
Building Data:
Building Name:
Building Use:
Year Built:
Years of Additions/Alterations:
Height:
Construction Type:
Pioneer Elementary School
School Facility Serving Grades K-4
1959
1978*, 1995*, and 1998*
One story with a mechanical mezzanine
Unreinforced stack bond masonry walls with
wood diaphragm; Wood post and beam system;
Concrete stem wall and footing foundation
*Year of construction may differ from what is listed. These dates were obtained from verbal
conversations with Ken Armstrong of the Salmon School District.
Pioneer Elementary School, Salmon, ID
Reference Documents:
• Architectural and Structural Construction Drawings, by
Charles W Johnston – Architect
Date: April 17, 1958
• Preliminary Site Evaluation
(Soils Investigation at 104 S. Warpath St., Salmon, ID) by,
Stephen F. Freiburger, PE, J-U-B Engineers, Inc
Date: January 6, 2001
Report No: 58048
• FEMA 310 Structural Evaluation Report of the Pioneer Elementary, by
Terrol Bateman, PE, Engineering Structural Solutions
Date: July 2007
Report No: 07241
• Pioneer Elementary School Visual Assessment, by
Janene A. Welch, PE, SE, Stapley Engineering
Date: June 23, 2009
Report No: 09051.L01
• Compressive Strength of Drilled Concrete Cores, by
Strata Geo-tech
Date: May 21, 2012
Report No: B012123A
• Pioneer Elementary School Visual Assessment, by
Janene A. Welch, PE, SE, Stapley Engineering
Date: July 17, 2012
Report No: 12060.L01
1.0 GENERAL
Scope:
This report is in response to the request of the Salmon School District for
DC Engineering to perform a visual structural observation of the Pioneer
Elementary School. Prior to the visual observation, I met with Joey Foote,
Superintendent of the Salmon School District, and Ken Armstrong, Facilities
Maintenance Manager of the Salmon School District, to discuss the intent
and scope of this report.
The visual observation of the building and surrounding property consists of
the following scope of work:
• On site survey of the building to ascertain the lateral and gravity
structural framing systems, evidence of any seismic upgrades during
past additions, and the general condition of the building.
• Review of the above mentioned Reference Documents.
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Pioneer Elementary School, Salmon, ID
•
•
•
•
Review of general geological information of the site attainable from
the United States Geological Survey (USGS) and the Idaho
Geological Survey.
Assessment of the structure to support environmental loads
including snow and seismic.
Identify structural vulnerabilities of both the gravity and seismic
resisting systems.
Development of my professional opinion on the adequacy of the
structure to support prescribed loads based on findings, published
materials, and engineering judgment.
Limitations:
This report has been prepared using the same level of competency for
professional structural engineering services presently maintained by other
practicing professional consultants performing similar work in the region.
This report has been prepared to meet the needs of the Salmon School
District and may not meet the needs of other parties.
The review of the structure was limited to available information. A visual
observation of the site was performed by Joe Lane on July 10, 2012. The
contents of this report are not intended to provide a complete structural
analysis of the building; limited structural calculations were performed.
Information provided to DC Engineering by the Salmon School District is
assumed to be reliable and comprehensive. A comprehensive cost
analysis of the recommended structural upgrades will not be performed.
Code related issues not pertaining to the structural system such as Means
of Egress, ADA requirements, energy efficiencies, fire ratings, and et cetera
have not been explored in detail and were not part of the scope of this
report. The report may briefly mention potential problems related to some
code issues outside of the structural system and these potential problems
should be investigated further by a professional with knowledge of the
subject matter.
Gravity Assessment:
The purpose of a gravity assessment is to determine the adequacy of a
structure to support gravity loads including: dead (self-weight of structure),
live (loads applied to the structure from occupants and their possessions),
snow, and rain. A visual observation along with as-built or construction
drawing are used to determine the size and material properties of the
structural elements.
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Pioneer Elementary School, Salmon, ID
Seismic Assessment:
The purposed of a seismic assessment is to determine the adequacy of a
structure to support earthquake loads and to identify structural
vulnerabilities in the seismic resisting system. Structural seismic
vulnerabilities are dependent on geological properties of the site, proximity
to seismic sources, and the physical properties of the structure. This report
uses information from the United States Geological Survey (USGS) to
determine the seismicity at the site; the building is then given a Level of
Seismicity classification in accordance with the ASCE 31-03.
A Tier 1 seismic evaluation, as defined by the ASCE 31-03, will be
conducted to investigate the physical and geological seismic hazards. A
visual observation along with as-built or construction drawings are used to
determine physical properties of the seismic resisting system including the
following: size, material strength, age of construction, and deterioration.
The seismic assessment is intended to identify potential deficiencies or
weaknesses that could contribute to the overall vulnerability of the structural
system. Other items that can contribute to the structural system’s
vulnerability are: completeness of load path, geometry of the building,
redundancy, types of materials used, detailing, adjacent structures, site
topography, and general condition of the structure.
Jurisdictional Requirements:
A phone conversation was conducted with Gary Goodman on July 12, 2012
to address any jurisdictional requirements of the structural evaluation. Gary
Goodman is the Building Inspector for the City of Salmon, ID and the
Administrator for the Lemhi County Building Department. The city currently
has adopted the 2009 International Building Code and has no requirements
for building investigations. The city requires a roof snow load of 25psf to be
used for design of new buildings that are in the vicinity of the Pioneer
Elementary School. It should be noted that the Idaho Association of
Building Officials recommends that a ground snow load of 35 psf should be
used for design of buildings in this area. The recommended 35 psf ground
snow load would then be used to calculate a roof snow load of 27 psf.
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Pioneer Elementary School, Salmon, ID
2.0 SEISMIC HISTORY
Background:
The potential seismic hazard of a site has several variables that impact the
probability of occurrence and intensity of an earthquake. Some variables
that affect the intensity of an earthquake are: building type, earthquake
magnitude, distance to epicenter, proximity to known faults, and soil
characteristics including, site classification, soil amplification, and
liquefaction. Large magnitude earthquakes have a lower probability of
occurring while lower magnitude earthquakes have a higher probability of
occurring for a given time period.
The following is from the Idaho Geological Survey’s website: “Geological
and seismological studies show that earthquakes are likely to happen in
any of several active zones in Idaho and adjacent states. Idaho is ranked
fifth highest in the nation for earthquake hazard. Only California, Nevada,
Utah, and Alaska have a greater overall hazard. Idaho has experienced
the two largest earthquakes in the contiguous United States in the last
thirty years—the 1959 Hebgen Lake earthquake (M7.5) and the 1983
Borah Peak earthquake (M7.3). Both tremors caused fatalities and millions
of dollars in damage. In all parts of Idaho, the historical record of
seismicity reveals at least a moderate threat from earthquakes.”
The subject property is classified as having a High Level of Seismicity as
defined by the ASCE 31-03. The Level of Seismicity is quantified by the
peak ground acceleration of an earthquake having a 2% probability of
exceedance in 50 years, or having a return interval of 2,500 years. The
values for peak ground acceleration are provided by the Unites States
Geological Survey. Under the 2009 International Building Code the
building would be classified as being in a Seismic Design Category D.
The most notable recent earthquake occurred on December 12, 2011,
having a magnitude of 2.6 and an epicenter approximately 5 kilometers
from the building site.
Faults:
Some of the faults that are in relative close proximity to the site are listed
in Table 1 – Site Proximity to Known Faults. The faults noted in Table 1
are major and lesser Holocene faults as listed by the Idaho Geological
Survey; these faults have all moved in the last 10,000 years. Most notable
are the lesser Holocene Borah Peak Scarps that moved in 1983. This is
not a comprehensive study of the faults and it should be noted that the
faults in the state of Montana have not been listed. Earthquakes do not
always occur along known faults; most notably the 1997 Northridge
Earthquake in California did not occur along a known fault. Figure 1 is a
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Pioneer Elementary School, Salmon, ID
map of the fault locations provided by the Idaho Geological Survey in
conjunction with Google Earth.
Table 1 – Site Proximity to Known Faults
Fault Name
Beaverhead Fault
Lemhi Fault
Lost River Fault
Lone Pine Peak Fault
Borah Peak Scarps Fault
41
59
78
88
117
Approximate Distance
Kilometers
Kilometers
Kilometers
Kilometers
Kilometers
SITE
LOST
RIVER
FAULT
LEMHI
FAULT
LONE
PINE
PEAK
FAULT
BEAVERHEAD FAULT
BORAH PEAK SCARPS
Figure 1 – Regional Fault Map (Idaho Geological Survey)
Soil Amplification:
Soil amplification is based on the site’s soil properties and profile. Soils can
either amplify or dissipate seismic energy as it moves from the epicenter to
the building site. Soft soils such as alluviums tend to amplify seismic waves
while stiff soils such as bedrock tend to de-amplify seismic waves.
Amplification can occur when seismic waves pass from rock into less rigid
material such as soil. Amplification can cause a building to experience
increased seismic motion.
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Pioneer Elementary School, Salmon, ID
Soil amplification for this site was based on the Preliminary Site Evaluation
of the soils by J-U-B Engineers (2000) which indicates a clayey top soil over
a layer of clay over gravel. The soil is assumed to be a Site Class D for
purposes of this evaluation. Soils at the site are expected to cause
moderate amplification of seismic energy.
Liquefaction:
According to the Idaho Geological Survey, “Liquefaction occurs during
strong earthquake ground shaking when saturated, cohesionless earth
materials lose strength due to high excess pore-water pressure. The
consequences of liquefaction can be catastrophic, including destruction of
railways, roads, bridge abutments, and building foundations. Liquefaction
susceptibility is highest in artificial fills and loose, sandy deposits that are
saturated with water. Such deposits may occur adjacent to rivers, streams,
and lakes, even in a semi-arid region like southern Idaho. Irrigation may
also increase liquefaction susceptibility by saturating deposits.”
The USGS, Idaho Geological Survey and other sources have mapped
liquefaction susceptibility in some regions of Idaho. Regional mapping for
Salmon, ID was not available to determine a more accurate assessment of
the potential hazard for liquefaction in this area. Based upon available data,
it is assumed that the potential for liquefaction to result from a seismic event
is low.
3.0 SITE AND BUILDING DATA
The Pioneer Elementary school was designed in 1958 by Charles W.
Johnston – Architect, and Robert J. Smith – Associate. Construction on the
school was completed circa 1959. When completed, the school consisted of
12 classrooms, 6 bathrooms, administration offices, a multi-purpose room,
boiler room, kitchen, and areas for general storage. The total building area
when completed was about 19,500 square feet.
The drawings state that the building was designed under the UBC. The
drawings state a roof design live load of 30 psf. Design live loads are also
stated for the slab on grade loading. Snow loads, wind loads, and seismic
loads were not outlined in the drawings. The drawings stated an assumed
allowable bearing pressure of 1,000 psf and that all footings “shall rest on
undisturbed earth” with a minimum embed of 8 inches. There was no
geotechnical report referenced or any further reference to soil preparation in
the drawings. The drawings stated that glued-laminated beams were to have
an allowable bending stress of 2,400 psi. All other material properties were
not listed on the drawings. The drawings do not specify any reinforcing in the
masonry walls.
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Pioneer Elementary School, Salmon, ID
The building site is situated on the northern corner of the intersection of
Sharkey St. and Highway 93 in Salmon, Idaho. The building site is relatively
flat with little elevation change around the site, see Photo 01. The Pioneer
Elementary School is located adjacent to the Middle School and across the
street from the school district offices.
The entire building is supported on conventional reinforced concrete footings
and stem walls with an interior slab on grade. The slab on grade is noted in
the drawings to be 4 inches thick and reinforced with “reinforcing mesh 6x6
10/10”. There is an approximately 5’-0” wide x 4’-8” tall steam tunnel that is
located directly beneath the floor slab with piping in it that was previously used
to serve steam to the building for heat. The tunnel runs continuous along the
outside edge of the building beneath the classrooms, multi-purpose room,
kitchen, and boiler room. The steam tunnel turns to the west where it exits the
building and runs underneath the sidewalk to the serve the middle school and
shop building.
The southeast portion of the building contains the kitchen, multi-purpose, and
boiler rooms and is one story. There is a mechanical mezzanine over the
storage room and bathrooms that are adjacent to the multi-purpose room.
There is an office mezzanine above the kitchen. The mechanical mezzanine
is framed with 2x8 ceiling joists that are supported by 2x6 walls with a gypsum
board finish each side on top of reinforced concrete footings. The average
roof height at the southeast portion of the building is approximately 17ft. Roof
construction over the multipurpose room consists of straight 3x6 tongue and
groove decking over 7” wide radial glued-laminated beams with varying depth
at 12’-0” on center supported by 16’ tall 8” x 7” glued-laminated columns. The
glued-laminated columns are partially concealed in a full height 2x6 wall on
both the east and west side of the multi-purpose room. On the south end of
the room is a full height 12” stack bond masonry wall. On the north side of the
room is an 8’-0” tall masonry wall with a 2x6 wall framed on top it continuous
to the roof.
The rest of the building is also one story with an average roof height of
approximately 13’-6”. Typical construction consists of continuous windows
along the outside edge of the classrooms with built up (3) 2x4 posts between
windows at 6’-0” on center. The classrooms are separated from the
breezeway/hallway with a partial height masonry wall extending 7’-4” above
the floor. There are clerestory windows on top of the masonry that extend to
the roof framing above. The outside edge of the breezeway/hallway was
originally constructed with 3” diameter pipe columns at 18’-0” on center.
Demising walls between the classrooms were constructed of 2x6 studs with a
½” gypsum board finish on each side of the wall. There were no footings
constructed under the demising walls. Roof construction consists of straight
2x6 tongue and groove over glued-laminated beams spaced at 6’-0” on
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Pioneer Elementary School, Salmon, ID
center. The glued-laminated beams are supported on the outer edges of the
building by the (3) 2x4 posts and the 3” diameter pipe columns that are noted
above. The glue-laminated beams are supported at the ridge by another
glued-laminated beam that spans 30’-0” between built up (4) 2x6 posts that
are located in the demising walls between the classrooms. These posts are
supported on conventional reinforced concrete isolated pad footings
There have been several renovations and additions to the building over the
years. Construction drawings were not available for any of the renovations
and additions. Around 1978 the covered breezeways were framed in with
what appears to be 2x4 stud walls with gypsum board to provide enclosed
hallway access to all the classrooms. The hallway skylights and clerestory
windows were covered with sheathing attached to existing framing with limited
or no nailing. The building was given a new standing seam metal roof around
this same time. Original roof construction was some form of an insulated
membrane roof with gravel over the top of the membrane.
Two more renovations occurred in the 1990’s. The first was circa 1995 and
consisted of 2 new classrooms being added on to the north-west end of the
building, see Photo 02. Around this same time 3 additional mechanical rooms
were constructed adjacent to the multi-purpose room and a mezzanine office
was framed in with stairs above the kitchen. Construction at this time
consisted of conventional continuous concrete footings and stem wall with 2x4
walls. The roof framing over the mechanical rooms consists of 2x roof joists
with a plywood roof diaphragm. The roof framing over the two new
classrooms consists of custom-made wood trusses plated with light-gauge
steel and nailed to the truss.
Circa 1998, a new library and 2 new classrooms were added south of the
east-west wing and to the east of the north-south wing, see Photo 03. This
addition was offset from the breezeway walls that had previously been framed
in by approximately 3ft and separated by a new wall constructed of running
bond concrete-masonry-units on two sides of the addition. The other two
sides of the addition was framed with 2x walls. After completion of this
addition the approximate square footage of the building is now 28,900 square
feet.
It does not appear that lateral loads (earthquake and wind) were taken into
consideration when the building was designed and constructed. The
drawings do not detail out any connection for transfer of diaphragm forces to
shear walls and there is no detailing for the out of plane support of the
unreinforced masonry walls. The drawings suggest that there are no chords
and collectors to transfer lateral forces to the few full height masonry walls that
are in the building. This is typical for buildings designed and constructed
during this time. Notable non-structural elements present at the time the
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Pioneer Elementary School, Salmon, ID
building was originally constructed are the following: hanging fluorescent lights
throughout the building, a 20” x 60” water storage heater on a pipe stand that
sits 5’-6” above the floor, and a heating and ventilation unit on the mechanical
mezzanine. The drawings do not state how any of these non-structural
elements are to be braced. Seismic design of non-structural elements was not
introduced into building codes until after completion of this building.
4.0 ASSUMPTIONS
The soils at the site have been assumed to be consistent with the findings
of a Preliminary Site Evaluation report by J-U-B Engineers for the property
located at 104 South Warpath, Salmon, Idaho. The Pioneer Elementary
building is approximately 0.25 miles west of the property located at 104
South Warpath. The ground elevation at the school is approximately 10
feet lower than the ground elevation at 104 South Warpath. The top 1-2
feet of soil is assumed to be clayey topsoil with silt. Below the clayey
topsoil with silt is a layer of fat clay extending down to about 5 feet below
grade. Gravels were generally encountered below 5 feet. Ground water
depths ranged from 5 feet to 8 feet below grade. The field investigation for
this report was performed on December 22, 2000. It is assumed that
ground water would be encountered closer to the surface in the spring and
summer months.
Based on the soil assumptions noted above the soil was classified as a Site
Class D for purposes of this report.
Based upon a visual observation of the soil and previous reports by Structural
Engineering Solutions (2007) and Stapley Engineering (2009), it is assumed
that there are sulfates in the soil. It is also assumed that the clayey soil has
high contents of montmorillonite, the main component of bentonite.
5.0 FINDINGS
Observation:
The building appeared to have been maintained in a clean and working
manner over the past 50+ years. There were numerous signs of wear and
tear that would be expected in a building of this age. The windows on the
exterior portion of the building appear to be from the original construction.
When standing next to these windows I could feel the temperature differential
between the outside and inside of the building. I assume the windows
perform poorly from an energy efficiency standpoint.
The wing of the building that is orientated east-west had an unpleasant smell
to it. The source of the smell was not identifiable. At the time of the
observation, the carpets had recently been shampooed throughout the
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Pioneer Elementary School, Salmon, ID
building. I do not believe that the shampooing of the carpets was the result of
the smell. No mold, dry-rot, foundation settlement, or insect infestation was
observed.
It was observed that there is not a fire sprinkler system in the building. The
building does contain an automated fire alarm. It is possible that the current
walls in the building are insufficient to prevent the spreading of fire in the case
of an event. There did not appear to be a fire separation wall between the
classrooms and the hallway corridor.
All gable walls at the original building, with the exception of the full height
masonry wall on the south side of the multi-purpose room, were constructed
of partial height masonry with 2x6 walls framed up to the roof on top of the
masonry. The 2x6’s are spaced at 32” on center are clad with a corrugated
plastic on the outside and no finish or insulation on the inside, see Photo 04.
The gable wall on the north side of the multi-purpose room is now clad on the
inside with gypsum board. Ken Armstrong stated that this was done 10-12
years ago and that no insulation was added at this time. The amount of uninsulated gable walls should be further investigated for energy efficiencies.
There was one interior 2x wood partition wall that I was able to move at the
base by hand. It appeared that there was no anchorage from the wall to the
slab at this location.
There were signs of foundation deterioration around the perimeter of the
building, see Photos 05 and 06. At a couple locations on the west side of the
building, rebar was exposed at the top of the concrete stem wall, see Photo
07. It appeared that someone had tried to patch this before and the material
used to patch the exposed rebar had fallen off again. Cause of the initial
foundation deterioration is assumed to be caused by a chemical attack from
sulfates in the soil. It is also possible that the concrete has little entrained air
in it, which makes it susceptible to freeze-thaw deterioration. Freeze-thaw
deterioration occurs when water gets in the cracks of the concrete and then
temperatures lower causing the water to freeze. As the water freezes, it
expands and results in cracking of the concrete.
At the front entry of the building there was minor cracking at the end of two of
the 12” masonry walls. At one of the locations cracking is presumed to be
caused by the wall being supported on an 8” stem wall causing some uneven
stress distribution in the wall and resulting in a minor crack, see Photo 08. At
the other location cracking is presumed to be caused by the lack of foundation
support due to deterioration of the concrete stem wall, see 09, and 10. The
mortar on the exterior of the building appeared to be intact and of sound
condition; this can most likely be attributed to the paint finish protecting the
mortar form climatic conditions such as wind and rain.
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Pioneer Elementary School, Salmon, ID
In the office mezzanine over the kitchen, I observed Ken Armstrong try to
remove a piece of wood trim at the top of the masonry wall. This was done by
prying a flat screw driver against the face of the masonry and under the piece
of wood trim. The masonry appeared to crumble easily under the prying force
and this method was abandoned. The masonry mortar at this same location
crumbled easily when I ran my fingers over the joints with light pressure. The
piece of trim was later removed using a different procedure. With the top of
the wall exposed, I was able to observe that one cell was reinforced with what
appeared to be a ½” diameter bar. Grout in the reinforced cell stopped 3
courses (12”) short of the top of the wall. The top of the wall was inspected for
rebar over a width of 8 cells (5’-4”) and this was the only piece of rebar visible.
In the empty cells, I was able to observe approximately 6 feet down into the
cell. I was not able to see any sign of horizontal reinforcing in the wall. There
was no other rebar observed in the masonry walls and the construction
drawings did not specify masonry reinforcing; therefore, it is assumed, the
masonry walls are unreinforced for purposes of this evaluation.
In two of the classrooms, I observed the concrete slab on grade heaving
approximately 1” above the rest of the floor. The slab was covered by carpet
that was not removed for further observance. I believe this is being caused by
the montmorillonite soil that is directly below the slab. As the moisture content
in the soil rises due to seasonal changes, the soil will swell causing localized
areas of high pressure on the underneath side of the slab. I also believe that
the sulfates in the soil are casing the interior slabs to deteriorate faster than
normal. I was told by Ken Armstrong that once the heave in the slab goes
down that the concrete quickly deteriorates and leaves a depressed area in
the slab. Ken said that the school district has already replaced the slab on
grades in 7 of the classrooms, see Photo 11.
The roof framing connecting to the concrete masonry wall that was
constructed during the 1998 addition was observed to have in sufficient
connections to brace the masonry wall for out of plane seismic loads, see
Photo 19.
The steam tunnel was observed under the sidewalk where it exits the building.
The concrete walls and slab appeared to be in good condition. The
underneath side of the sidewalk was observed form inside the steam tunnel.
There was exposed rebar in one location with unconsolidated concrete and
aggregate pockets around it, see Photo 12. It appears that the rebar
exposure is a result of faulty construction and not deterioration of the
concrete. In some locations where the galvanized form deck was still in place,
it was deteriorating and falling down, see Photo 13. The concrete sidewalk
when observed from the top appeared to be in good condition.
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Pioneer Elementary School, Salmon, ID
Non-structural items that were observed include the following: in-line
propane heaters, a heating and venting unit, ductwork, and basketball
hoops. The heating and ventilation unit on the mechanical mezzanine
was originally detailed to have vibration isolators. Currently the piece of
equipment sits on neoprene pads and is not anchored to the wood curb
that it is sitting on. The wood curb is not anchored to the mezzanine, see
Photo 14. In-line heaters had been installed sometime in the last 30 years
in each room and are hanging from the roof framing above. The in-line
heaters were not adequately braced for seismic resistance, see Photo 15.
All ductwork that was observed in the building was hanging more than 12”
below the roof framing and was not adequately braced for seismic
resistance. The basketball hoops in the multi-purpose room appeared to
be adequately braced for seismic resistance.
There was no sign that there had been any seismic upgrades to the building.
Further, it did not appear that there were any structural upgrades performed
since the building had originally been constructed. The two additions in the
1990’s appear to have a positive impact on the lateral stability of the building.
However, since there are no drags or collectors present in the diaphragms,
the overall effect of these two additions do little to improve the seismic
performance of the building. All adjacent buildings are located a safe distance
away from the building and do not represent a hazard.
Structural Deficiencies:
Structural checklists from the ASCE 31-03 detailing my findings of the seismic
evaluation have been provided in the appendix. These findings identify
several structural seismic deficiencies.
The building has physical characteristics that add to the potential of a seismic
failure. The building has an irregular footprint. The building did not appear to
contain a complete load path in any direction to resist seismic loads and
therefore has zero redundancy. Redundancy is preferable and required for
some buildings by modern day building codes. The partial height masonry
walls do not provide lateral stability to the building and none of the masonry
walls are braced to resist out of plane forces. The masonry joints on the
interior of the building appear to be deteriorating and it is assumed that
stresses in masonry resulting from a seismic event would exceed allowable
design stresses. The building has several deficiencies for transferring inplane forces to the shear walls including: insufficient connections of
diaphragms to masonry walls, and there are no identifiable drags, collectors,
cross ties, or chords present in the diaphragms. The diaphragm aspect ratios
and spans are larger than that acceptable for diaphragms constructed of
straight sheathing. The isolated pad footings at the interior of the building do
not contain adequate ties to resist seismic forces without consideration of the
soil (this is based on the assumption that the soil is classified as Site Class D).
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Pioneer Elementary School, Salmon, ID
The glass elevations (Photos 16 and 17) along the classroom wings, the
reliance on rigid diaphragm action and the lack of drags and connections
represents a significant seismic vulnerability in the building.
Review of Prior Reports:
A prior report by Stapley Engineering (2012), states that the roof truss over
the addition at the north end of the building have connections that are
overstressed by as much as 66%, considering a 27 psf snow load. Using the
25 psf snow load as directed by the building official, would result in the roof
truss connections being overstressed by 61%.
A prior FEMA 310 report by Engineering Structural Solutions (2007) provides
a cost estimate for structural upgrades. The report noted that all foundation
walls and footings should be removed and replaced with an estimated cost of
$2.8 million. It is my opinion that seismic upgrades to the foundation would
not necessitate the entire foundation being replaced and that upgrade costs
would be substantially less than the $2.8 million noted in Engineering
Structural Solutions’ (2007) report. A cost analysis was not performed by DC
Engineering.
6.0 CONCLUSIONS AND RECOMMENDATIONS
General Inference:
The deterioration and cracking in the concrete foundation appears to be only
cosmetic and does not have an impact on the structural integrity of the
building. The deterioration in foundation should be monitored and maintained
as necessary or it is possible that it could lead to structural stability issues.
The concrete stem wall with the exposed rebar should be repaired to
eliminate the possibility of further deterioration. This should be designed and
detailed by a professional. The observed masonry cracking appears to be
only cosmetic with no impact to the structural integrity of the building.
The slab on grades in the building should be monitored for future heaving and
should be replaced as necessary to prevent tripping hazards. There are a few
different options to mitigate this from occurring in the future when a slab is
replaced. Possibilities included providing reinforcing in the slabs, utilizing type
V cement, and treating the soil with a lime application. Replacement of the
slabs should be done under the direction of a professional and further
investigation should be done during demolition. The soils under the slab
should also be investigated at this point.
The lack of observed firewalls in the building presents a concern. I believe a
study should be done to determine if there is a life-safety risk and any
deficiencies should be mitigated.
Page 14
Pioneer Elementary School, Salmon, ID
Building Stability Assessment:
The building is noted to have several physical and material deficiencies that
are known to lead to instability in whole or part of the building under gravity
and earthquake loads. The un-braced partial height masonry walls represent
a potential falling hazard. The unreinforced full height masonry walls in
conjunction with possible mortar issues add to the overall instability of the
building. Stack bond masonry walls are known to perform poorly in seismic
events. In addition, all of the deficiencies noted above further reduce the
overall lateral stability of the building.
Compared to buildings constructed in accordance with the International
Building code; I would consider the overall lateral stability of the building to be
very low.
Recommendations:
The roof trusses over the addition at the north end of the building should be
repaired or replaced under the supervision of a professional engineer. The
Idaho General Safety & Health Standards published by the Idaho Division of
Building Safety (IGSHS) defines a dangerous building under section 030.09.
IGSHS section 030.09.d states the following: “A dangerous building, structure,
or facility exists whenever the stress in any materials, member, or portion
thereof, due to all live and dead loads, is more than one and one-half ( 1½)
times the working stress or stress allowed in the Building Code for new
buildings of similar structure, purpose, or location.” As calculated by Stapley
Engineering, the roof truss connections are overstressed by 61%. This 61%
overstress meets the definition of a dangerous building. According to this
definition of a dangerous building, it is my recommendation that actions are
taken by the Salmon School District to mitigate the possible failure of the roof
trusses. This should be done before winter and heavy snows are expected.
The following non-structural components should be braced to resist seismic
loads: all in-line propane heaters, the heating and venting unit, and ductwork
throughout the building in accordance with current code recommendations.
Due to the number of deficiencies in the building, I would recommend
mitigating seismic hazards by having a design professional perform a Tier 2
Evaluation in accordance with the ASCE 31-03 to address the deficiencies
identified in the Tier 1 Evaluation stated earlier in this report. It is anticipated
that deficiencies will be identified in the Tier 2 Evaluation. After the Tier 2
Evaluation is complete, the design professional could choose to perform a
Tier 3 Evaluation or mitigate potential hazards by providing a design for
seismic upgrades. This decision to perform a Tier 3 Evaluation should be
based on economic impact or other advantages of providing a Tier 3
Evaluation. It is my recommendation that a Tier 2 Evaluation is performed in
Page 15
Pioneer Elementary School, Salmon, ID
conjunction with a design for seismic upgrades to mitigate the potential
hazards and to not have a Tier 3 Evaluation performed. Upon completion of
the seismic upgrade design, I recommend that the school board have a plan
to allow for construction to start.
I do not believe there is an immediate life safety risk in the building except
for the trusses at the northern addition due to snow loads. However,
immediate is a relative term and the life safety risks from a seismic event
are high and efforts to mitigate these risks should be taken. All upgrades
and retrofits should be done under the supervision of a professional
engineer with knowledge and experience of the type of work being
performed.
7.0 PRIORITIZED LIST OF DEFICIENCIES
7.1
7.2
7.3
Repair roof trusses over the addition at the north end of the building
to accommodate design snow loads.
Brace all non-structural components to resist seismic loads.
Have a Tier 2 Evaluation in accordance with the ASCE 31performed
in conjunction with a design for seismic upgrades. Seismic upgrades
should be constructed as soon as possible.
If you have any questions regarding the content of this report, please feel
free to contact me to discuss. DC Engineering would be happy to further
assist the Salmon School District in any capacity deemed necessary.
Sincerely,
Joe Lane, PE
Engineer
8/13/12
Joe Chapman, PE, SE
Structural Department Manager
Enclosures:
Appendix A – ASCE 31-03 Seismic Evaluation of Existing Buildings
Checklists 3.7.15, 3.7.15S, 3.8, 3.9.1, and 3.9.2
Appendix B – Photographic Journal of Site Observation
Appendix C – Construction drawings from 1958
Appendix D – Prior Reports by Other Consultants
Page 16
Pioneer Elementary School, Salmon, ID
Appendix A – ASCE 31-03
Seismic Evaluation Checklists
• 3.7.15 Basic Structural Checklist for Building Type URM: Unreinforced
Masonry Bearing Walls with Flexible Diaphragms
• 3.7.15S Supplemental Structural Checklist for Building Type URM:
Unreinforced Masonry Bearing Walls with Flexible Diaphragms
• 3.8 Geologic Site Hazards and Foundation Checklist
• 3.9.1 Basic Nonstructural Component Checklist
• 3.9.2 Intermediate Nonstructural Component Checklist
Screening Phase (Tier 1)
3.7.15
Basic Structural Checklist for Building Type URM: Unreinforced Masonry
Bearing Walls with Flexible Diaphragms
This Basic Structural Checklist shall be completed where required by Table 3-2.
Each of the evaluation statements on this checklist shall be marked Compliant (C), Non-compliant
(NC), or Not Applicable (N/A) for a Tier 1 Evaluation. Compliant statements identify issues that are
acceptable according to the criteria of this standard, while non-compliant statements identify issues
that require further investigation. Certain statements may not apply to the buildings being evaluated.
For non-compliant evaluation statements, the design professional may choose to conduct further
investigation using the Tier 2 Special Procedure for Unreinforced Masonry or the Tier 3 Evaluation
Procedure.
C3.7.15
Basic Structural Checldist for Building Type URM
These buildings have bearing walls that cons~st of unreinforced (or lightly reit:tforced) brick, stone, or
concrete block masonry. Wood floor and roof :framing consists:9fwoodjoists, glulam beams, and
wood posts or small steel columns. Steel tloor and roof framing consists of st~I beams or open web
joists, steel girders, and steel columns. Lateral forces are resisted by Uie brick or concrete blo.ck.
masonry shear walls. Diaphragms consist of straight or diagonal lumber sheathing, structural wood
panels, or untapped metal deck, and are flexible relative to the walls. Foundat~ons consisfofbrick or
concrete spread footings or deep foundations.
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Building System
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C
NC
N/A
LOAD PATH : The structure shall contain a minimum of one complete load path for Life Safety
and Immediate Occupancy for seismic force effects from any horizontal direction that serves to
transfer the inertial forces from the mass to the foundation. (Tier 2: Sec. 4.3. 1. 1)
There does not appear to be a continuous load path in any direction.
C
NC
N/A
ADJACENT BUILDINGS: The clear distance between the building being evaluated and any
adjacent building shall be greater than 4 percent of the height of the shorter building for Life Safety
and Immediate Occupancy. (Tier 2: Sec. 4.3.1 .2)
C
NC
N/A
MEZZANINES: Interior mezzanine levels shall be braced independently from the main structure,
or shall be anchored to the lateral-force-resisting elements of the main structure. (Tier 2:
Sec. 4.3.1.3)
C
NC
N/A
WEAK STORY: The strength of the lateral-force-resisting system in any story shall not be less
than 80 percent of the strength in an adj acent story, above or below, for Life Safety and Immediate
Occupancy. (Tier 2: Sec. 4.3. 2.1)
C
NC
N/A
SOFT STORY: The stiffuess of the lateral-force-resisting system in any story shall not be less than
70 percent of the lateral·force-resisting system stiffness in an adjacent story above or below, or less
than 80 percent of the average lateral-force-resisting system stiffness of the three stories above or
below for Life Safety and Immediate Occupancy. (Tier 2: Sec. 4.3.2.2)
C
NC
N/A
GEOMETRY: There shall be no changes in horizontal dimension of the lateral-force-resisting
system of more than 30 percent in a story relative to adjacent stories for Life Safety and Immediate
Occupancy, excluding one-story penthouses and mezzanines. (Tia- 2: Sec. 4.32.3)
C
NC
N/A
VERTICAL DISCONTINUITIES: All vertical clements in the lateral-force-resisting system shall
be continuous to the foundation. (Tier 2: Sec. 4.3.2.4)
Interior masonry walls are partial height and are not continuous to the roof diaphragm. Interior gypboard shearwalls do not appear to have adequate foundation support or connections to foundation.
There doesn't not appear to be any connections to transfer diaphragm forces to shear walls.
3-98
Seismic Evaluation of Existing Buildings
ASCE 31-03
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C
NC
N/A
MASS: There shall be no change in effective mass more than 50 percent from one story to the next
for Life Safety and Immediate Occupancy. Light roofs, penthouses, and mezzanines need not be
considered. (Tier 2: Sec. 4.3.2.5)
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NC
N/A
DETERIORATION OF WOOD: There shall be no signs of decay, shrinkage, splitting, fire
damage, or sagging in any of the wood members, and none of the metal connection hardware shall
be deteriorated, broken, or loose. (Tier 2: Sec. 4.3.3. 1)
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NC
N/A
MASONRY UNITS: There shall be no visible deterioration of masonry units.
Sec. 4.3.3.7) There is minor cracking in the masonry but no signs of deterioration.
C
NC
N/A
MASONRY JOINTS: The mortar shall not be easily scraped away from the joints by hand with a
metal tool, and there shall be no areas of eroded mortar. (Tier 2: Sec. 4.3.3.8)
(Tier 2:
There are signs of mortar deterioration around the exterior of the building and mortar on the inside of the building crumbled when rubbed by hand.
C
NC
N/A
UN REINFORCED MASONRY WALL CRACKS: There shall be no existing diagonal cracks in
the wall elements greater than 1/8 inch for Life Safety and l/ 16 inch for Immediate Occupancy, or
out-of-plane offsets in the bed joint greater than 118 inch for Life Safety and 1/16 inch for
Immediate Occupancy, and shall not form an X pattern. (Tier 2: Sec. 4.3.3.11)
Lateral-Force-Resisting System
C
NC
N/A
REDUNDANCY: The number of lines of shear walls in each principal direction shall be greater
than or equal to 2 for life Safety and Immediate Occupancy. (Tier 2: Sec. 4.4.2. I .I)
There are no shear walls in the building that have been adequately detailed or constructed to properly transfer diaphragm forces to the foundation.
C
NC
N/A
SHEAR STRESS CHECK: The shear stress in the unreinforced masonry shear walls, calculated
using the Quick Check procedure of Section 3.5.3.3, shall be less than 30 psi for clay units and 70
psi for concrete units for Life Safety and Immediate Occupancy. (Tier 2: Sec. 4.4.2.5. I)
Shear stresses were not calculated but it assumed the stress will exceed 70 psi in some of the masonry walls do to inadequate
detailing and the limited number of full height shear walls.
Connections
C
NC
N/A
WALL ANCHORAGE: Exterior concrete or masonry wa lls that are dependent on the diaphragm
for lateral support shall be anchored for out-of-plane forces at each diaphragm level with steel
anchors, reinforcing dowels, or straps that are developed into the diaphragm. Connections shall
have adequate strength to resist the connection force calculated in the Quick Check procedure of
Section 3.5.3.7. (Tier2: Sec. 4.6.1.1} Interior masonry walls are not continuous to roof diaphragm and have no other form of
bracing. Exterior masonry walls do not appear to have any anchorage to resist out-of-plane forces; additionally this was not detailed in
the drawings.
C
NC
N/A
WOOD LEDGERS: The connection between the wall panels and the diaphragm shall not induce
cross-grain bending or tension in the wood ledgers. (Tier 2: Sec. 4.6.1.2)
C
NC
N/A
TRANSFER TO SHEAR WALLS: Diaphragms shall be connected for transfer of loads to the
shear walls for Life Safety and the connections shall be able to develop the lesser of the shear
strength of the walls or diaphragms for Immediate Occupancy. (Tier 2 Sec. 4.6.2.1)
C
NC
N/A
GIRDER/COLUMN CONNECTION: There shall be a positive connection utilizing plates,
connection hardware, or straps between the girder and the column support. (Tier 2: Sec. 4.6.4.1)
The columns between the windows on the outside edge of the classroom do not have any positive connection utilizing plates, straps,
or connection hardware to the roof beams or above or the foundation. Additionally these columns are un-braced in both directions.
ASCE 31-03
Seismic Evaluation of Existing Buildings
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Supplemental Structural Checklist for Building Type URM: Unreinforced
Masonry Bearing Walls with Flexible Diaphragms
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This Supplemental Structural Checklist shall be completed where required by Table 3-2. The Basic
Structural Checklist shall be completed prior to completing this Supplemental Structural Checklist.
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NC
N/A
PROPORTIONS: The height-to-thickness ratio of the shear walls at each story shall be less than
the following for Life Safety and Immediate Occupancy (Tier 2: Sec. 4.4.2.5.2):
Top story of multi-story building
First story of multi-story building
All other conditions
C
NC
N/A
9
15
13
All full height masonry walls have a nominal
thickness of 8" and are taller than 8'-8"; therefore,
they exceed the height-to-thickness ratio of 13.
MASONRY LAY-UP: Filled collar joints of multi-wythe masonry walls shall have negligible
voids. (Tier 2: Sec. 4.4.2.5.3)
C
NC
N/A
CROSS TIES: There shall be continuous cross ties between diaphragm chords.
Sec. 4.5. 1.2) There was no sign of diaphragm chords or cross ties throughout the building.
C
NC
N/A
OPENINGS AT SHEAR WALLS: Diaphragm openings immediately adjacent to the shear walls
shall be less than 25 percent of the wall length for Life Safety and 15 percent of the wall length for
Immediate Occupancy. (Tier 2: Sec. 4.5.1.4) Adjacent to the masonry walls separating the classrooms from the hallway
C
NC
N/A
OPENINGS AT EXTERIOR MASONRY SHEAR WALLS: Diaphragm openings immediately
adjacent to exterior masonry shear walls shall not be greater than 8 feet long for Life Safety and 4
feet long for Immediate Occupancy. (Tier 2: Sec. 4.5.1 .6)
C
NC
N/A
PLAN IRREGULARITIES: There shall be tensile capacity to develop the strength of the
diaphragm at re--entrant comers or other locations of plan irregularities. This statement shall apply
to the Immediate Occupancy Performance Level only. (Tier 2: Sec. 4.5.1.7)
(Tier 2:
is where the old skylights used to be located. At some point the skylights were taken out and replaced with some form of sheathing. The
sheathing appears to have no positive connection to the rest of the roof framing.
Building is being evaluated to the Life Safety Level. Plan irregularities do exist and the roof diaphragm has not be strengthened at these
locations.
C
NC
N/A
DIAPHRAGM REINFORCEMENT AT OPENINGS: There shall be reinforcing around all
diaphragm openings larger than SO percent of the building width in either major plan dimension.
This statement shall apply to the Immediate Occupancy Performance Level only. (Tier 2:
Sec. 4.5. I .8)
C
NC
N/A
STRAIGHT SHEATHING: All straight sheathed diaphragms shall have aspect ratios less than 2to-1 for Life Safety and 1-to-1 for Immediate Occupancy in the direction being considered. (Tier 2:
The majority of diaphragm aspect ratios exceed 2-1. The roof diaphragm at the wing of the building that runs
Sec. 4.5.2.1) east-west has an aspect ratio of exceeding 4-1.
C
NC
N/A
SPANS: All wood diaphragms with spans greater than 24 feet for Life Safety and 12 feet for
Immediate Occupancy shall consist of wood structural panels or diagonal sheathing (Tier 2:
Sec. 4.5.2.2) All roof diaphragm spans in the building exceed 24 feet and are sheathed with straight 2x6 or 3x6 tongue and
grove decking.
C
NC
N/A
UNBLOCKED DIAPHRAGMS: All diagonally sheathed or unblocked wood structural panel
diaphragms shall have horizontal spans Jess than 40 feet for Life Safety and 30 feet for Immediate
Occupancy and shall have aspect ratios Jess than or equal to 4-to-1 for Life Safety and 3-to-1 for
Immediate Occupancy. (Tier 2: Sec. 4.5.2.3)
C
NC
N/A
NON-CONCRETE FILLED DIAPHRAGMS: Untopped metal deck diaphragms or metal deck
diaphragms with fill other than concrete shall consist of horizontal spans of less than 40 feet and
shall have span/depth ratios Jess than 4-to-1. This statement shall apply to the Immediate
Occupancy Perfonnance Level only. (Tier 2: Sec. 4.5.3.1)
Seismic Evaluation of Existing Buildings
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ASCE 31-03
Screening Phase (Tier 1)
C
NC
N/A
OTHER DIAPHRAGMS: The diaphragm shall not consist of a system other than wood, metal
deck. concrete, or horizontal bracing. (Tier 2: Sec. 4.5. 7.1)
Connections
C
NC
N/A
STIFFNESS OF WALL ANCHORS: Anchors of concrete or masonry walls to wood structural
elements shall be installed taut and shall be stiff enough to limit the relative movement between the
wall and the diaphragm to no greater than 1/8 inch prior to engagement of the onchors. (Tier 2:
Sec. 4.6.1.4) Wall anchors do exist to transfer in-plane or out-of-plane forces to the masonry walls.
C
NC
N/A
BEAM, GIRDER, AND TRUSS SUPPORTS: Beams, girders, and trusses supported by
unreinforced masonry walls or pilasters shall have independent secondary columns for support of
vertical loads. (Tier 2: Sec. 4.6.4.5)
Where unreinforced masonry walls support beams or girders, there are no secondary columns.
ASCE 31-03
Seismic Evaluation of Existing Buildings
3 -101
Screening Phase (Tier 1)
3.8
Geologic Site Hazards and Foundations Checklist
This Geologic Site Hazards and Foundations Checklist shall be completed where required by
Table 3-2.
Each of the evaluation statements on this checklist shall be marked Compliant (C), Non-compliant
(NC), or Not Applicable (N/A) for a Tier 1 Evaluation. Compliant statements identifY issues that are
acceptable according to the criteria of this standard, while non-compliant statements identifY issues
that require further investigation. Certain statements may not apply to the buildings being evaluated.
For non-compliant evaluation statements, the design professional may choose to conduct further
investigation using the corresponding Tier 2 Evaluation procedure; corresponding section numbers
are in parentheses following each evaluation statement.
Geologic Site Hazards
The following statements shall be completed for buildings in levels of high or moderate seismicity.
C
NC
N/A
LIQUEFACTION: Liquefaction-susceptible, saturated, loose granular soils that could jeopardize
the building's seismic performance shall not exist in the foundation soils at depths within 50 feet
under the building for Life Safety and Immediate Occupancy. (Tier 2: Sec. 4.7.1.1)
C
NC
N/A
SLOPE FAILURE: The building site shall be sufficiently remote from potential earthquakeinduced slope failures or rockfalls to be unaffected by such failures or shall be capable of
accommodating any predicted movements without fa ilure. (Tier 2: Sec. 4.7. 1.2)
C
NC
N/A
SURFACE FAULT RUPTURE: Surface fault rupture and surface displacement at the building site
is not anticipated. (Tier 2: Sec. 4.7.1.3)
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The following statement shall be completed for all Tier I building evaluations.
C
NC
N/A
FOUNDATION PERFORMANCE: There shall be no evidence of excessive foundation movement
such as settlement or heave that would affect the integrity or strength of the structure. (Tier 2:
Sec. 4. 7.2.1)
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The following statement shall be completed for buildings in levels of high or moderate seismicity being evaluated to the
Immediate Occupancy Performance Level.
C
NC
N/A
DETERlORATION: There shall not be evidence that foundation elements have deteriorated due to
corrosion, sulfate attack, material breakdown, or other reasons in a manner that would affect the
integrity or strength of the structure. (Tier 2: Sec. 4. 7.2.2) There are visible signs of foundation deterioration
which is assumed to be caused by sulfate attack. However, this does not appear to affect the integrity or strength of the structure.
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The following statement shall be completed for all Tier I building evaluations.
C
NC
N/A
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POLE FOUNDATIONS: Pole foundations shall have a minimum embedment depth of 4 feet for
Life Safety and Immediate Occupancy. (Tier 2: Sec. 4.7.3.1)
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The following statements shall be completed for buildings in levels of moderate seismicity being evaluated to the
Immediate Occupancy Performance Level and for buildings in levels of high seismicity.
C
NC
ASCE 31-03
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OVERTURNING: The ratio of the horizontal dimension of the lateral-force-resisting system at the
foundation level to the building height (base/height) shall be greater than 0.6SD. (Tier 2:
Sec. 4.7.3.2) Was not calculated.
Seismic Evaluation of Existing Buildings
3-119
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Screening Phase (Tier 1)
C
NC
N/A
C
NC
N/A
DEEP FOUNDATIONS: Piles and piers shall be capable of transferring the lateral forces between
the structure and the soil. This statement shall apply to the Immediate Occupancy Perfonnance
Level only. (Tier 2: Sec. 4.7.3.4)
C
NC
N/A
SLOPING SITES: The di ffere nce in foundation embedment depth from one side of the building to
another shall not exceed one story in height. This statement shall apply to the lmmediate
Occupancy Perfonnance Level only. (Tier 2: Sec. 4. 7.3.5)
TIES BETWEEN FOUNDATION ELEMENTS: The foundation shall have ties adequate to resist
seismic forces where foo tings, piles, and piers are not reslrained by beams, slabs, or soils classified
as Class A, B, or C. (Section 3.5.2.3.1, Tier 2: Sec. 4. 7.3.3) Isolated pad footings are not tied to the rest of the
foundation. These isolated pad footings provided support for approximately 50% of the roof load.
3-120
Seismic Evaluation of Existing Buildings
ASCE31-03
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Basic Nonstructural Component Checklist
This Basic Nonstructural Component Checklist shall be completed where required by Table 3-2.
Each of the evaluation statements on this checklist shall be marked Compliant (C), Non-compliant
(NC), or Not Applicable (N/A) for a Tier I Evaluation. Compliant statements identify issues that are
acceptable according to the criteria of this standard, while non-compliant statements identify issues
that require further investigation. Certain statements may not apply to the buildings being evaluated.
For non-compliant evaluation statements, the design professional may choose to conduct further
investigation using the corresponding Tier 2 Evaluation procedure; corresponding section numbers
are in parentheses following each evaluation statement.
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Partitions
C
NC
N/A
UNREINFORCED MASONRY: Unreinforced masonry or hollow clay tile partitions shall be
braced at a spacing equal to or less than 10 feet in levels of low or moderate seismicity and 6 feet in
levels of high seismicity. (Tier 2: Sec. 4.8.1.1)
Cei1ing Systems
C
NC
N/A
SUPPORT: The integrated su~'Pended ceiling system shall not be used to laterally support the tops
of gypsum board, masonry, or hollow clay tile partitions. Gypsum board partitions need not be
evaluated where only the Basic Nonstructural Component Checklist is required by Table 3-2. (Tier
2: Sec. 4.8.2. 1)
Light Fixtures
C
NC
N/A
EMERGENCY LIGHTING: Emergency lighting shall be anchored or bmced to prevent falling
during an earthquake. (Tier 2: Sec. 4.8.3.1)
Cladding and Glazing
C
NC
N/A
CLADDING ANCHORS: Cladding components weighing more than I 0 psf shall be mechanically
anchored to the exterior wall framing at a spacing equal to or Jess than 4 feet. A spacing of up to 6
feet is permitted where only the Basic Non structural Component Checklist is required by Table 3-2.
(Tier 2: Sec. 4.8.4.1)
C
NC
N/A
DETER! ORATION: There shall be no evidence of deterioration, damage or corrosion in any of
the connection elements. (Tier 2: Sec. 4.8.4.2)
C
NC
N/A
CLADDING ISOLATION: For moment !Tame buildings of steel or concrete, panel connections
shall be detailed to accommodate a story drift ratio of 0.02. Panel connection detailing for a story
drift ratio ofO.Ol is permitted where only the Basic Nonstructural Component Checklist is required
by Table 3-2. (TiCT 2: Sec. 4.8.4.3)
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NC
N/A
N/A
MULTI-STORY PANELS: For multi-story panels attached at each floor level, panel connections
shall be detailed to accommodate a story drift ratio of 0.02. Panel connection detailing for a story
drift mtio ofO.O I is permitted where only the Basic Nonstructural Component Checklist is required
by Table 3-2. {Tier 2: Sec. 4.8.4.4)
BEARING CONNECTIONS: Where bearing connections are required, there shall be a minimum
of two bearing connections for each wall panel. (Tier 2: Sec. 4.8.4.5)
Seismic Evaluation Standard
ASCE 31-02
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NC
N/A
INSERTS: Where inserts are used in concrete connections, the inserts shall be anchored to
reinforcing steel or other positive anchorage. {Tier 2: Sec. 4.8.4.6)
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C
NC
N/A
PANEL CONNECTIONS: Exterior cladding panels shall be anchored out-of-plane with a
minimum of 4 connections for each wall panel. Two connections per wall panel are permitted
where only the Basic Nonstructural Component Checklist is required by Table 3-2. (Tier 2:
Sec. 4.8.4. 7)
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C
NC
N/A
0
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SHELF ANGLES: Masonry veneer shall be supported by shelf angles or other clements at each
floor 30 feet or more above ground for Life Safety and at each floor above the first floor for
Immediate Occupancy. (fier 2: Sec. 4.8.5.1)
C
NC
N/A
C
NC
N/A
WEAKENED PLANES: Masonry veneer shall be anchored to the back-up adjacent to weakened
planes, s uch as at the locations of fl ashing. (Tier 2: Sec. 4.8.5.3)
C
NC
N/A
DETERIORATION: There shall be no evidence of deterioration, damage, or corrosion in any of
the connection elements. (Tier 2: Sec. 4.8.5.4)
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TIES: Masonry veneer shall be connected to the back-up w ith corrosion-resistant ties. The ties
shall have a spacing equal to or less than 24 inches with a min imum of one tie for every 2-2/3
square feet. A spacing of up to 36 inches is permitted where only the Basic Nonstructural
Component Checklist is required by Table 3-2. (Tier 2: Sec. 4.8.5.2) The construction drawings specify
Corrugate G.I. Ties at 16" on center vertically and 32" on center horizontally.
Parapets, Cornices, Ornamentation, and Appendages
C
NC
N/A
URM PARAPETS: There shall be n o laterally unsupported unreinforced masonry parapets or
cornices with height-to-thickness ratios greater than 1.5. A height-to-thickness ratio of up to 2.5 is
permitted where on ly the Basic Nonstructural Component Checklist is required by Table 3-2. (Tier
2: Sec. 4.8.8. 1)
C
NC
N/A
CANOPIES: Canopies located at building exits shall be anchored to the structural framing at a
spacing of 6 feet or less. An anchorage spacing of up to I 0 feet is permitted where only the Basic
Nonstructural Component Checklist is required by Table 3-2. {Tier 2: Sec. 4.8.8.2)
Masonry Chimneys
C
NC
N/A
URM CHIMNEYS: 'No unreinforced masonry ch imney shall extend above the roof surface more
than twice the least dimension of the chimney. A height above the roof surface of up to three times
the least dimension of the chimney is permitted where only the Basic Nonstructural Component
Checklist is required by Table 3-2. (Tier 2: Sec. 4.8.9.1)
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Stairs
C
NC
N/A
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URM WALLS: W alls around stair enclosures shall not consist of unbraced hollow clay tile or
unreinforced masonry w ith a height-to-thickness ratio greater than 12-to-1. A height-to-thickness
ratio of up to 15-to-1 is permitted where only the Basic Nonstructural Component Checklist is
required by Table 3-2. (Tier 2: Sec. 4.8.10. 1)
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C
NC
ASCE 31·03
N/A
STAIR DETAILS: In moment frame structures, the connection between the stairs and the structure
shall not rely on s hallow a~chors in concrete. Alternatively, the stair details shall be capable of
accommodating the drift calculated us ing the Quick Check procedure of Section 3.5.3.1 without
including tension in the anchors. (Tier 2: Sec. 4.8.1 0.2)
Seismic Evaluation of Existing Buildings
3 ·123
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Building Contents and Furnishing
C
NC
N/A
TALL NARROW CONTENTS: Contents over 4 feet in height with a height-to-depth or height-towidth ratio greater than 3-to-1 shall be anchored to the floor slab or adjacent structural walls. A
height-to-depth or height-to-width ratio of up to 4-to-1 is pennitted where only the Basic
Nonstructural Component Checklist is required by Table 3-2. (Tier 2: Sec. 4.8.11.1)
Mechanical and Electrical Equipment
C
NC
N/A
EMERGENCY POWER: Equipment used as part of an emergency power system shall be mounted
to maintain continued operation after an earthquake. (Tier 2: Sec. 4.8.12. I)
C
NC
N/A
HAZARDOUS MATERIAL EQUIPMENT: HVAC or other equipment containing hazardous
material shall not have damaged supply lines or unbraced isolation supports. (Tier 2:
Sec. 4.8. 12.2)
C
NC
N/A
DETERIORATION: There shall be no evidence of deterioration, damage, or corrosion in any of
the anchorage or supports of mechanical or electrical equipment. (Tier 2: Sec. 4.8. J2.3)
C
NC
N/A
ATTACHED EQUIPMENT: Equipment weighing over 20 lb that is attached to ceilings, walls, or
other supports 4 feet above the floor level shall be braced. (Tier 2: Sec. 4.8.12.4)
None of the equipment was adequately braced.
Piping
C
NC
N/A
C
NC
N/A
FIRE SUPPRESSION PIPING: Fire suppression p1pmg shall be anchored and braced in
accordance with NFPA-13 (NFPA, 1996). (Tier 2: Sec. 4.8.13.1)
There are no fire sprinklers in the building.
FLEXIBLE COUPLINGS: Fluid, gas, and fire suppression piping shall have flexible couplings.
(Tier 2: Sec. 4.8. 13.2)
Hazardous Materials Storage and Distribution
C
NC
N/A
TOXIC SUBSTANCES: Toxic and hazardous substances stored in breakable containers shall be
restrained from falling by latched doors, shelf lips, wires, or other methods. (Tier 2: Sec. 4.8.15.1)
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3-124
Seismic Evaluation of Existing Buildings
ASCE 31·03
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Intermediate Nonstructural Component Checklist
This Intermediate Nonstructural Component Checklist shall be completed where required by
Table 3-2. The Basic Nonstructural Component Checklist shall be completed prior to completing
this Intermediate Nonstructural Component Checklist.
Ceiling Systems
C
NC
N/A
LAY-JN TILES: Lay-in tiles used in ceiling panels located at exits and corridors shall be secured
with clips. (Tier 2: Sec. 4.8.2.2)
C
NC
N/A
INTEGRATED CEILINGS: Integrated suspended ceilings at exits and corridors or weighing more
than 2 pounds per square foot shall be laterally restrained with a minimum of four diagonal wires or
rigid members attached to the structure above at a spacing equal to or less than I2 feet. (Tier 2:
Sec. 4.8.2.3)
C
NC
N/A
SUSPENDED LATH AND PLASTER: Ceilings consisting of suspended lath and plaster or
gypsum board shall be attached to resist seismic forces for every 12 square feet of area. (Tier 2:
Sec. 4.8.2.4)
Light Fixtures
C
NC
N/A
INDEPENDENT SUPPORT: Light fixtures in suspended grid ceilings shall be supported
independently of the ceiling suspension system by a minimum of two wires at diagonally opposite
comers of the fixtures. (Tier 2: Sec. 4.8.3.2)
Cladding and Glazing
C
NC
N/A
GLAZING: Glazing in curtain walls and individual panes over 16 square feet in area, located up to
a height of 10 feet above an exterior walking surface, shall have safety glazing. Such glazing
located over 10 feet above an exterior walking surface shall be laminated annealed or laminated
heat-strengthened safety glass or other glazing system that will remain in the frame when glass is
cracked. (Tier 2: Sec. 4.8.4.8)
Parapets, Cornices, Ornamentation, and Appendages
C
C
NC
NC
N/A
N/A
CONCRETE PARAPETS: Concrete parapets with height-to-thickness ratios greater than 2.5 shall
have vertical reinforcement. (Tier 2: Sec. 4.8.8.3)
APPENDAGES: Cornices, parapets, signs, and other appendages that extend above the highest
point of anchorage to the structure or cantilever from exterior wall faces and other exterior wall
ornamentation shall be reinforced and anchored to the structural system at a spacing equal to or less
than 10 feet for Life Safety and 6 feet for Immediate Occupancy. This requirement need not apply
to parapets or cornices compliant with Section 4.8.8.1 or 4.8.8.3. (Tier 2: Sec. 4.8.8.4)
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Masonry Chimneys
C
NC
N/A
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ANCHORAGE: Masonry chimneys shall be anchored at each floor level and the roof. (Tier 2: Sec.
4.8.9.2)
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ASCE 31-03
Seismic Evaluation of Existing Buildings
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Mechanical and Electrical Equipment
C
NC
N/A
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VIBRATION ISOLATORS: Equipment mounted on vibration isolators shall be equipped with
restraints or snubbers. (Tier 2: Sec. 4.8.12.5) The heating and ventilation unit on the mechanical mezzanine was
originally detailed to have vibration isolators. Currently the piece of equipment sits on neoprene pads and is not anchored to the wood
curb that it is sitting on. The wood curb is not anchored to the mezzanine.
Ducts
C
NC
N/A
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STAIR AND SMOKE DUCTS: Stair pressurization and smoke control ducts shall be braced and
shall have flexible connections at seismic joints. (Tier 2: Sec. 4.8. I4.1)
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3-126
Seismic Evaluation of Existing Buildings
ASCE 31..03
Appendix B – Photographic
Journal of Site Observation
by DC Engineering
Photo 01 – Building Site
Photo 02 – Classroom addition to southwest wing around 1995
Photo 03 – Library and classroom addition around 1998
Photo 04 – Typical gable wall construction, 2x studs on top of partial height masonry wall
Photo 05 – Foundation deterioration at west side of building
Photo 06 – Foundation deterioration at north side of building
Photo 07 – Exposed rebar in foundation at west side of building
Photo 08 – Minor crack in end of 12” masonry wall supported by 8” foundation at south side of building
Photo 09 – Minor crack in end of a 12” masonry wall at the south side of the building
Photo 10 – Foundation deterioration under end of 12” masonry wall
Photo 11 – Concrete slab deterioration in warehouse adjacent to Pioneer Elementary School , it is
assumed that the same process is happening to the slabs in the school that were covered by carpet and
not visible to inspect.
Photo 12 – Exposed rebar at underneath side of sidewalk over steam tunnel
Photo 13 – Galvanized form deck deteriorating at steam tunnel
Photo 14 – Heating and venting unit on wood curb
Photo 15 – In-line propane heaters and ductwork
Photo 16 – Glass elevation along the outside edge of classrooms on north side of building
Photo 17 – Glass elevation along the outside edge of classrooms on west side of building
Photo 18 – Cracks in glued-laminated beams at multipurpose room
Photo 19 – Concrete masonry unit wall at 1998 addition with lack of out of plane connections
Photo 20 – Partial height masonry wall and 2x walls with no sheathing and clad with corrugated plastic
at the 1995 addition to the southeast corner of the building