2. Design Criteria
Facility Type: Residential Building
Location : Arlington, TX
Floor: One Storey
Plan Area: 12ft x 20ft ( Two Rooms)
Wood used: Southern Pine
Building Height: 13 ft
Eaves Height: 3ft
Floor Height: 10 ft
8. ASD Adjustment Factors
Load Duration Factor CD 1.25
Wet Service Factor CM 1
Temperature factor Ct 1
Beam Stability Factor CL 1
Size Factor CF depends on size
Flat Use Factor Cfu 1
Incising factor Ci 1
Repettitive Member factor Cr 1
Column Stability factor Cp 0.211
Buckling Stiffness Factor CT 1
Bearing Area factor Cb 1
9. Truss Design
Tension Member Design
Dead Load: 21 psf
Roof Live Load: 20 psf
Wind load: 16.63 psf
Most critical combination was D+Lr
Critical Load: 32.8 psf
Truss spaced at 4 ft.
Tension force: 0.6 kips
The member No. 2- Southern Pine 2’’ x
3’’ was found suitable for the tension
force
Compression Member Design
Dead Load: 21 psf
Roof Live Load: 20 psf
Wind load: 16.63 psf
Most critical combination was D+Lr
Critical Load: 32.8 psf
Truss spaced at 4 ft.
Most Critical Compression force: 0.85 kips
The member No. 2- Southern Pine 2’’ x 3’’
was found suitable for the compresssion
force
10. Beam Design
Designed according NDS provisions( ASD Method)
Beam Length: 10ft
No. 2 Southern Pine
Design for Flexure
Actual Bending Stress: 775.4 psi
Allowable bending stress: 1443.75 psi Bending OK
Design for Shear
Actual Shear Stress: 59.76 psi
Allowable shear Stress: 240.625 psi Shear OK
Check for Deflection
Allowable deflection: 0.5 in
Actual deflection: 0.078 in Deflection OK
Beam Size selected 4’’ x 10’’
11. Column Design
Reference design value( Compressive stress) Fc= 1450 psi
Column Length: 10 ft
Designed as a fixed- hinged column ke= 0.8
No. 2 Southern Pine
Axial compressive force in the end column: 1332 lb
Axial compressive force in the middle column: 2664 lb
Axial capacity of the column 4” X 4” = 6457.93 lb
USE COLUMN 4” x 4” SIZE
12. Panel Design
2’’ framing members spaced at 24’’
Total design load: 41 lb/ft
3 ply Panels selected with span rating 24/16
Design for Flexure:
Max Bending moment: 196 lbin
Panel Bending strength FbS’: 400 lbin/ ft of panel width Bending OK
Design for shear
Maximum Shear: 46.125 lb
Panel Shear through the thickness FvTv ‘: 71.25 lb Shear OK
Design for deflection
Allowable deflection: 0.095 in
Actual deflection: 0.0732 in Deflection OK
USE 3 ply Panels of thickness 7/16 inches
13. Wind Load Design
ASCE 7-10, Wind Speed 115 mph,
Exposure category B
Wind Pressure 24.46 psf
Uniform Wind load of 220.14 lb/ft at
roof.
Diaphragm dimension= 20 X 12
Designed based on SDPWS
Diaphragm and Shear Wall design
with Chord member design and
Deflection check
14. Diaphragm Design
Reaction at ends = R = 2201.4 lb
Shear at Diaphragm = v= 183.45 plf
Tension = Compression in Chord = 5504 lb
Selected wood structural panel using table 4.2A designed as
Blocked from SDPWS.
Selected 5/16” nominal panel thickness of structural grade 1.
6d nail size with nail spacing at diaphragm and nail spacing at
other panel edges to be 6in.
From Table 4.2A, Allowable shear = 295 plf > Shear at
Diaphragm = v= 183.45 plf. OK
15. Chord Design
Max moment= 11007 lb-ft.
Tension = Compression in Chord = 5504 lb
Assume two No 2, 2X6 Southern Pine dimensional
lumber as chord members
Allowable Tension = 10890 lb > 5504 lb, OK
Allowable Compression = 7474 lb > 5504 lb, OK
Deflection Checked as per 4.2.2 of SDPWS
Calculated deflection = 0.176 < Allowable
deflection = .45in, OK
16. Shear Wall Design
Unit Shear at Shear wall= v= 183.45 plf
Designed as per Section 4.3 for SDPWS.
Shear wall in N-S direction does not have any opening in our
case.
Selected wood structural panel using table 4.3A Wood Based
panels from SDPWS.
Used 5/16” nominal panel thickness- Structural 1 grade.
6d nail size and, min fastener penetration in framing member
to be 1-1/4 with panel edge fastener spacing to be 6 in.
Allowable shear = 280 plf > Shear at Diaphragm = v= 183.45
plf. OK
17. Shear Wall Design
Moment at base= 33021 lb-ft.
Tension = Compression in Chord = 2751 lb
Assume No 2, 2X6 Southern Pine dimensional lumber as
chord members
Allowable Tension = 10890 lb > 2751 lb, OK
Allowable Compression = 3835 lb > 2751 lb, OK
Deflection Checked as per 4.3.2 of SDPWS
Calculated deflection = 0.41 < Allowable deflection =
.45in, OK
