HomeMy WebLinkAbout1993_Structural Recommendations Report_Monte Clark Engineering= MONTE CLARK ENGINEERING
STRUCTURAL CONSULTANTS
November 17, 1993
LINCOLN SCHOOL MUSEUM: STRUCTURAL RECOMMENDATIONS REPORT
We have completed our review of the structural condition of the existing Lincoln School. The
recommendations resulting from that review are contained in this report. In addition to the
information obtained through visual observations and calculations, we have reviewed and
incorporated the information presented in a report by Mahan and DeSalvo Consulting Engineers
dated August 31, 1988 entitled "REPORT OF INSPECTION, ANALYSIS AND
RECOMMENDATIONS FOR REPAIR OF LINCOLN SCHOOL AND ADDITIONS". This
report will not duplicate the information contained in that document, but will attempt to build on
that information to develop specific recommendation for strengthening the structure. This
information can then be used to develop an accurate estimate of the costs required for renovation.
MAIN BUILDING (Original construction)
ROOF AND SECOND FLOOR CEILING
• Create a diaphragm at the second floor ceiling level. Accomplish this by adding one layer of
plywood to all of the second floor ceiling, either above or below ceiling joists.
• Connect four existing fifteen foot long concrete walls, on each side of the second floor
cloak rooms, to the ceiling and roof diaphragm above. Accomplish this by constructing a
wood stud wall sheathed with 1/2" plywood each side from the top of the concrete walls
(at second floor ceiling level) to the roof sheathing above. Connections to the new wood
shearwalls would be made at the second floor ceiling level and roof level.
• Connect two existing concrete walls located between second floor classrooms to the ceiling
diaphragm above. Accomplish this'by bolting a steel angle and wood ledger to the top of
the wall to provide ceiling diaphragm connections.
• Install wall ties with rosettes at the perimeter of the second floor ceiling at 6-0" spacing.
• Install wall ties with rosettes at the perimeter of the roof where roof extends more than
4'-0" above second floor ceiling level. Space at 6-0" o.c.
SECOND FLOOR
• Connect the second floor concrete joists to the East and West walls for adequate shear
transfer. Accomplish this with wall ties with rosettes as noted below.
• Install wall ties with rosettes at the perimeter of the second floor.
• Brace the second floor balcony parapets.
216 First Avenue South, Suite 250
Seattle, Washington 98104
Tel (2n6)623-166i • Fax (206) 623-3773
ln7StWmmn.Suite I
Ketchikan, Alaska 49901
Tel (407122;-4161 - Fax (4071247.73s3
FIRST FLOOR
• Repair damaged existing concrete slab on grade concrete.
• Replace timber subfloor as required for museum functions.
WALLS
• Tuckpoint exterior walls as required.
• Install parapet braces where parapet height exceeds 1.5 times the wall thickness.
• Strongback the masonry piers between the large windows on the front and rear elevations
with steel beams. (Approximate beam size will be T.S. 6x6x 1/2)
EAST AND WEST WING ADDITIONS
ROOF
• Remove existing roofing.
• Add 1/2" plywood sheathing to the top of existing roof sheathing to create a diaphragm.
• Provide new attachments of the new roof diaphragm sheathing to the perimeter walls.
• Install wall ties with rosettes at the perimeter of the roofs.
• Connect roof joist to interior bearing walls and trusses with steel strap ties at 4'-0" o.c.
rFLOOR
• Replace East Wing wood floor where rotten or deteriorated. Use either compacted fill and a
concrete slab on grade or wood, beam, post and spread footing construction.
WALLS
• Rebuild portion of southeast brick wall approximately six feet in length that has significantly
deteriorated due to roof downspout water washing of the mortar.
• :Tuckpoint exterior walls as required.
• Install parapet braces where parapet height exceeds 1.5 times the wall thickness.
• Install new crawl space vents where crawl space occurs.
LIBRARY ADDITION AND EXISTING SERVICE BUILDING
GENERAL
• Replace roof and second floor framing where rotten or deteriorated.
• Install 1/2" plywood sheathing at roof and second floors for a diaphragm.
• Install wall ties with rosettes at the perimeter of the roofs and second floor.
• Strengthen existing masonry walls used as shear walls.
• Rebuild cracked portion of the fan room south wall.
• Brace parapets.
• Tuckpoint exterior walls as required.
ADDITIONAL INFORMATION
The original building second floor concrete joists have been calculated. to have an allowable
.superimposed load carrying capacity of approximately 65 psf. Assuming a ceiling load of 10
psf and a new flooring load of 5 psf, the resulting live load carrying capacity is
approximately 50 psf.
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