HomeMy WebLinkAbout1602 Butler St Technical - BuildingTECHNICAL
Permit 0
Address 6oZ 5 50 '.e-r 5
Project description 36' ).e,
13,4' h
E•QivNel
Date the permit vves---fi-Raled oG otl'
Number of technical pages �Z
00N 1 of 31
*t. oF
Post Frame Building Calculations Prepared By
RAMON M RIBA, P E
4627 MANOR PARK DR NW
ROCHESTER, MN 55901
TEL (507) 287 -0086
EFAX (707) 929 -1588
EMAIL RMRIBA @CHARTER NET
Date
Owner
Address
County
City, State
Building Span
Building Length
Eave Height
Roof Pitch
Avg Roof Height
Design
Seismic Design Category
Wind Zone 100Mph
Exposure C
Enclosed Structure YES
Roof Live Load 25 00 psf
Roof Dead Load 3 3 psf
Ceiling Load 1 0 psf
Soil 2000/150 psf
LOAD CALCULATIONS
WIND LOAD
Primary Frames and Systems Method 1 Normal Force Method
Design wind pressures for main wind force resisting systems are given by Table
1609 6 2 1(1) p 322 These pressures are multiplied by the height /exposure
coefficient in Table 1609 6 2 1(4) and the importance factor from Table 1604 5
The combined height exposure and gust factor coefficient shall be evaluated at
the mean roof height for pressures on roofs and leeward walls
ROOF
INCREASE Ce @<15 (((DELTA Ce Ce @<15' 10) (MEAN ROOF height 15))
1 21 (((1 29 1 21) 10) (16 67 15)
WALLS
1 237 for mean roof height
EXPIRES
October 16, 2004
BILL SIPE
1602 S BUTLER ST
PORT ANGELES, WA
32 ft
36 ft
14 ft
4 12
16 67 ft
IBC -00
1
1 21 for eave height of windward wall
Basic wind speed 100 mph
Iw importance factor for wind 1
H1 and H2 are given by Figure 1 Building Schematic Wind pressures have
positive signs for inward pressures and negative signs for outward
pressures suction
3 922 psf -13 368 psf
H2 5 33 1
1
1 1
H1 14 1 1
14 320 psf -12 384 psf
1 1
1 1
1 1
Figure 1 Building Schematic
Wind perpendicular to the roof ridge
where qWW design windward wall pressure psf
qWR design windward roof pressure psf
qLW design leeward wall pressure psf
qLR design leeward roof pressure psf
qWW 14 320 psf
qWR 3 922 psf
qLR -13 368 psf
qLW -12 384 psf
Earthquake Load
Occupancy Category 4
Since the building is one story and has an occupancy category 4, we may
use the simplified static lateral force procedure
Not having any site specific soil condition data, a Site Class Definition D'
is used
Page 2 of 31
t
Geographical location of building
1602 S BUTLER ST
PORT ANGELES WA
Building natural period
T 0 020 (h)
T 0 020 (16 67) 0 75 0 165 sec
Since T TO 2 0 2 sec, Sa Fa Ss
Since we have a framing system to support gravity loads and shear walls
to carry lateral loads our building falls into the Building Frame
Systems category
In addition our building is a light -frame structure with shear walls
consisting of metal cladding instead of plywood sheeting, so
R 6 5 32)
Determine the weight of the structure
Wtotal WSideWall WEndWalls WRoof (Bender Woeste, p 13)
WSideWall Length Eave Height psf 2 walls
WSideWall 36 ft 14 ft 2 5 psf 2 walls
2520 00 lb
WEndWall (Span Eave Height 2 walls) (Span Roof Height) psf
WEndWall (32 ft 14 ft 2 walls) (32 ft 5 33 ft) 2 5 psf
1546 67 lb
Wroof (Span Overhang) (Length Overhang) Deadload
WRoof (32 ft 0 ft 0 ft) (36 ft 0 ft) 4 3 psf
5159 24 lb
WTotal 2520 00 lb 1546 67 lb 5159 24 lb
9,226 lb
Determine the seismic coefficient
Page 3 of 31
For a site class D
Fa 1 44
Fv 2 24
Ss 0 64
S1 0 315
Thus
SDS (2/3) Fa Ss
SDS (2/3) 1 44 0 64 0 614
SD1 (2/3) Fv S1
SD1 (2/3) 2 24 0 315 0 470
Cs 1 2 SDS R
1 2* 0 614 6 5= 0 113
For the simplified procedure, the base shear is calculated as follows
V Cs W
V 0 113 9 226 lb
1 046 lb
Determine the Redundancy Factor
p must be between 1 and 1 5 1< p 1 5
Eccentricity Analysis
Accidental Eccentricity e 5 %L
F Shearwall force due to eccentricity
V Story Shear
F 05V
ri 55V) (10 /Lw)) V
Page 4 of 31
ri 5 5/ Lw
One story i 1
ri Rmax
Ab ground floor area
p 2 (20 /(Rmax sqr(Ab)))
p 2 (20 (0 172 sqr(1152)))
p -1 428
Then p 1
1 1 =1 5 OK
WALL GIRT DESIGN
Wall Girts (40 375 BETWEEN) 2 x 6 1650f -1 3E MSR 12' bays
Tributary Area (48 in 12 in) 12 sft 48 sft
From Table TABLE 1609 6 2 1(2)
Wind pressure 25 600 psf
Standard Girts
BENDING
P 25 600 psf
W 25 29 psf (1 ft ^2 144 ^2) 41 875 in 7 35 pli
Mmax wL ^2 8
16627 31 in -lbs
SM ((b 2) d) 6
Page 5 of 31
(Bender Woeste, p 16)
(Hoyle Woeste, p 381)
(NDS 3 3 2, eqn 3 3 -4 p 16)
SM 7 56 in ^3
Fb Mmax /SM
16627 31 in -lbs 7 56 in ^3
2198 65 psi
Fb' Fb (CD CL Cfu CR)
CD 1 6
CL (beam stability factor) 1 0
Cfu 1
Cr 1 15
p 28)
FbMax 1650 psi 1 6 1 1* 1 15 2640 psi
2198 65 psi 2640 psi, Therefore wind load checks OK
Therefore use 2 x 6 1650f -1 3E MSR with 2 10d common nails each end
Roof Purlins (12' bays 2 x 6 HEM -FIR2 24 oc
Assumptions
Dead Load Calcs
0 06 2 0 12 psf
ROOF PURLIN DESIGN
4 12 roof slope (18 435 degree roof angle)
Trusses spaced 12 -ft o c
Purlin span 11 875 -ft
24 in purlin spacing
1 43 psf dead load
(NDS 3 3 3 1 p 16)
(NDS Supp Table 4C, p 34)
(NDS 4 3 4
Steel average thickness 0157 in (Vic West Steel)
Steel weight 490 pcf (Lindley Whitaker, Table 6 -1, p 137)
Therefore 490 pcf 0157 in 12 in (40 625 in /36 in) 723 psf
Fiberglass blanket and Batt insulation 06 lb /ft ^2 /in
(Manbeck, et al Table 6 1, p 132)
The following formula shall be used to determine the density in lb /ft ^3 of
wood (NDS Supp p 8)
density 62 4 [G 1 G(0 009) (m c [1 m c 100]
Page 6 of 31
(NDS 3 3 2, eqn 3 3 -2, p 16)
(NDS Table 2 3 1 p 9)
in which
G specific gravity of wood 0 43 for Hem Fir(NDS Table 8A, p 56)
m c moisture content of wood
density 62 4 (0 43 (1 (0 43 0 009 0 19))) (1 (0 19 100))
lb /ft ^3
Lumber density per unit area lb /ft ^3 144 in ^2 0 187 lb(ft ^3 /in ^2)
Unif distributed load (1 5 in 5 5 in 0 187 lb /(ft ^3 in ^2) (1 ft)
(12 in 24 in)
5)
0 770 psf
1 613 psf 0 723 psf 0 12 psf 0 770 psf
Dead Load is 1 613 psf
25 00 psf roof snow load
Cd 1 15 for snow
Page 7 of 31
BENDING
SNOW LOAD
Wt [25 00 psf (24 12 ft cos 18 435)] (1 613 psf 24 12 ft)
(UBC Eqn 12 -12 p 2-
50 6619 04 plf
Wt 50 6619 04 plf 12 in /ft 4 222 pli
Solve for the bending moment and bending moment and bending stress about
the x -x axis (Hoyle Woeste p 320)
Mxx Wt cos L 2 8
Mxx ((4 222 pli cos 18 435) 141 7386 5 in 2) 8
9533 811 in -lb
Sxx (1 5 in (5 5 in 2)) 6 7 56 in 3 (NDS Supp p 8)
fbxx Mxx in -lb Sxx in 9533 811 in -lb 7 56 in
(NDS Eqn 3 3 2, p 16)
1260 669 psi
Fbxx' Fb (CD CL CF CR)
Fb 850 psi
CD 1 15
(NDS Table 2 3 1 p 5)
(NDS Supp Table 4C, p 35)
(UBC Section 2316 2 Amend 6 p 2 -291)
CL 1 (NDS 3 3 3 3, p 16)
CF 1 3
Cr 1 15 (NDS 4 3 4, p 28)
Fbxx 850 psi 1 15 1 1 3 1 15 1461 36 psi
1260 669 psi 1461 36 psi therefore bending stress for snow load checks OK
DESIGN DIAPHRAGMS
Background
The diaphragm panel systems have been tested for shear capacity using
recommendations from ASTM E455 -76 Static Load Testing of Framed Floor or
Roof Diaphragm Constructions for Buildings and ASAE EP484 Diaphragm
Design of Metal -Clad Post -Frame Rectangular Buildings
Limitations
The relative impact on shear strength of each component from the diaphragm
testing has not been defined The characteristics of the metal cladding and
fasteners specified herein meet or exceed the tested products The
characteristics of the framing lumber meet or exceed the Specific Gravity
G of the tested product, Spruce- Pine -Fir G 0 42
Diaphragm Testing Data Applicability
Applicable for buildings that utilize the method of diaphragm design to
resist design wind loads The test data are not applicable for roofs with
skylights Diaphragm Testing Results Table 1
Diaphragm Testing Results Table 1
Maximum
Shear Intensity
I (lbs /ft)
Roof Wall
Sections Sections
110 lbs /ft 160 lbs /ft
Construction
Page 8 of 31
Field Screws #10 x 1 -1/2 next to each major
rib 9 o c
Top Bottom Screws #14 x 1 -1/2 at BOTH
sides of each major rib
164 lbs /ft 173 lbs /ft Field Screws #10 x 1 -1/2 next to each major
rib 9 o c
Top Bottom Screws #10 x 1 -1/2 at BOTH
sides of each major rib
Stitch Screws #12 x 5/8 at 9 -3/8 on center
through all overlaps
1997 UBC Table 23- II -I -1
598 6 lbs /ft 7/16 osb applied directly to framing with 8d
Calculate the Maximum Roof Shear Intensity, I (lbs /ft) This is the shear
per foot of slope length that occurs at the end walls of the building
common nails 2 on center at panel edges
6 on center intermediate framing members
Per footnote number #1 SG 0 42 use
Structural 1 base value of 730# 82
(Per footnote #4 panels applied long
dimensions over studs use 15/32 values)
When the wall columns are supported at floor level so as to prevent
rotation of the base of the column the Maximum Roof Shear Intensity
I (lbs /ft) can be calculated by
I 3/8 qww H1 L qlw H1 L qwr H2 L
qlr H2 L 2 W
(The Alumax Roof Diaphragm Brochure 1991)
where qww design windward wall pressure (psf)
qwr design windward roof pressure (psf)
qlw design leeward wall pressure (psf)
qlr design leeward roof pressure (psf)
L the building length in feet
W the building width in feet
H1 the outside wall height not inside clear)
H2 the height from the eave to the ridge
Where
I [3/8 ((14 320 psf 14 ft 36 ft) -12 384 psf 14 ft
36 ft)) ((3 922 psf 5 33 ft 36 ft)
-13 368 psf 5 33 ft 36 ft))] (2 32 ft)
I 100 56 lbs /ft
The following minimum diaphragm requirements are needed
Page 9 of 31
Field Screws #10 x 1 -1/2 next to each major rib 9" o c Top Bottom
Screws #14 x 1 -1/2 at BOTH sides of each major rib
Calculate the Maximum Endwall Shear Load Vendwall (lbs /ft), by multiplying
the maximum roof shear intensity I, by the building end -wall width W
(Bender Woeste, p A -30 A -33)
Vendwall I W
Vendwall 3 217 95 lbs 100 56 lbs /ft 32 ft
Calculate the Allowable End -Wall Shear Capacity, SC
BACKWALL
SC W DW R
DW the door or opening width in feet, or distance between end -wall
structural posts surrounding the door, whichever is greater If more
than one door is installed DW is the total of door widths
R the allowable end -wall shear strength in lbs /ft from Table 1
Multiplying this value by the one -third increase in allowable stresses
for all combinations including W or E, We end up with the following
R 160 lb /ft 1 33 212 8 lb /ft
SC back endwall 6,809 6 lbs (32 ft 0 ft) 212 8 lbs /ft
SC W DW R
R 160 lb /ft 1 33 212 8 lb /ft
SC front endwall 851 2 lbs (32 ft 28 ft) 212 8 lbs /ft
Checking by equation for adequacy
Vendwall SC
3,217 95 lbs 5107 2 851 2 lbs
R 160 lb /ft 1 33 212 8 lb /ft
Column Calculations
Step 1 Calculate the roof diaphragm stiffness Ch by using a stiffness
adjustment procedure based upon the total number of sheet -to- purlin
fasteners
Aside from panel end fasteners panel length is proportional to the number
of fasteners when the pattern of sheet -to- purlin fasteners in the
diaphragm is maintained for the predicted building diaphragm
This is taken from the Design of Commercial Post -Frame Buildings (1997)
where
1 P a
C1 2 DeltaS b
for a simple beam test where
P 0 4 Pultimate
(ASAE EP484 1, Eqn 4, p 526)
Page 10 of 31
Putimate ultimate strength of panel
P 0 4 9600
P 3840
DeltaS deflection at P adjusted for sinking supports
DeltaS 0 235
a Frame Spacing
a 12 ft
b test panel length parallel -to- corrugations
b 11 667 ft
C1
1 3840 12 ft
2 0 235 11 667 ft
01 8 403 41 lb /in stiffness of the test panel
Calculate Stiffness of One Roof Slope
b a
C2 01
b Sf
where
C2 stiffness of diaphragm being predicted(lb /in
01 stiffness of test panel (lb /in
b roof slope length(ft)
b test panel length
a width of test panel(ft)
Sf frame spacing of diaphragm being predicted(ft)
b 16 ft cos 18 435
Page 11 of 31
(Townsend p 4)
(Townsend, p 4)
(Anderson Bundy Ch 6)
b' 16 87 ft
a 12 ft
Sf 12 ft
C2 11,810 63 lb /in 8,403 41 lb /in 16 87 ft 12 ft) (12 ft
12 ft)
Calculate Stiffness of Roof with Two Equal Sides
The stiffness of the entire roof diaphragm with two equal sides can be
calcuated by the following equation (Anderson Bundy)
Ch 2 C2 cos ^2 roof slope
where
Ch roof diaphragm stiffness(lb /in
Ch 2 11 810 63 lb /in Cos ^2 18 435)
Ch 21 259 13 lb /in
STEP 2 Calculate k the frame stiffness
k (6 E I) (H1 ^2 ((0 7 d) H1)
E modulus of elasticity of the post psi
E' E CI
CI 95
(NDS Table 2 3 1 1, p 11)
E' 1300000 psi 95 1235000 psi (NDS Supp Table 4D, p 39) See Hem -Fir
I moment of inertia of the post in ^4
I b x d"3 12
256 00 6 8 "3 12
H1 wall height in inches
H1 168 in
d embedment depth in inches
d 40 00 in
k 342 913 lb /in (6 1235000 psi 256 00 in'4) ((168 in ^2)
7 40 00 in 168 in))
STEP 3 Calculate R the lateral restraining force of the roof
diaphragm (Bender Woeste, p 45)
The lateral restraining force can be calculated as follows
(Skaggs Eqn 2)
For full Wind combinations
R Sf ((Hi (qww qlw) ((2 8 d) (3 H1))) (8
((0 7 d) H1)) H2 (qwr qlr))
(Skaggs Eqn 1)
(NDS Supp
R 12 ft ((14 ft (14 320 psf -12 384 psf)
((2 8 3 333 ft) (3 10 333 ft))) (8 7 3 000 ft)
10 333 ft)) 5 33 ft (3 922 psf -13 368 psf))
Page 12 of 31
p 8)
R 2,869 00 lbs
For 1/2 Wind combinations
R Sf ((H1 ((qww /2) (qlw /2)) ((2 8 d) (3 H1))) (8
((0 7 d) H1)) H2 ((qwr /2) (qlr /2)))
R 12 ft ((14 ft (14 320/2 psf -12 384/2psf)
((2 8 3 333 ft) (3 10 333 ft))) (8 7 3 000 ft)
10 333 ft)) 5 33 ft (3 922/2 psf -13 368/2 psf))
R 1 434 50 lbs
STEP 4 Calculate the Diaphragm Factor mD (Bender Woeste, p 45 -46)
First we must determine the ratio of frame -to -roof diaphragm stiffness
k Ch 0 0161 342 913 lb /in 21,259 13 lb /in (Bender Woeste, p 45)
Frames 4
From Table 1 of Skaggs mD 0 96
STEP 5 Calculate Shear at Top of the Windward Post
The Shear at the top of each post is calculated by the following
(Skaggs Eqn 3)
For full Wind combinations
V 1 2 ((R mD) Sf ((H1 (qww qlw) ((2 8 d) (3 H1))
(8 ((0 7 d) H1)) H2 (qwr qlr)))
V 1 2 2 869 00 lb 0 96 12 ft ((14 ft
(14 320 psf -12 384 psf) ((2 8 3 333 ft) (3 14 ft)))
(8 ((0 7 3 333 ft) 14 ft)) 5 33 ft (3 922 psf
-13 368 psf)))
V 916 42 lb
For 1/2 Wind combinations
V 1 2 ((R mD) Sf ((H1 ((qww /2) (qlw /2)) ((2 8 d)
(3 H1))) (8 ((0 7 d) H1)) H2 ((qwr /2) (qlr /2))))
V 1 2 2 869 00 lb 0 96 12 ft ((14 ft
(14 320/2 psf -12 384/2 psf) ((2 8 3 333 ft) (3 14 ft)))
(8 ((0 7 3 333 ft) 14 ft)) 5 33 ft (3 922/2 psf
-13 368/2 psf)))
V 458 21 lb
STEP 6 Calculate Maximum Post Moments M1 and M2
(Bender Woeste, p 46 -47)
The moment at the groundline can be calculated as follows
Page 13 of 31
k1 0 97 (the correction factor from Table 2 of Skaggs)
For full Wind combinations
M1 kl H1 (V ((Sf qww H1) 2)) (Skaggs Eqn 4)
M1 0 97 14 ft 916 42 lb ((12 ft 14 320 psf
14 ft) 2)) 12 in
M1 29 670 04 in -lb
For 1/2 Wind combinations
M1 kl H1 (V ((Sf (qww /2) H1) 2)) (Skaggs Eqn 4)
M1 0 97 14 ft 458 21 lb ((12 ft (14 320 psf /2)
14 ft) 2)) 12 in
M1 21 249 96 in -lb
If V is positive the maximum positive moment moment above groundline
can be calculated
k2 1 13 (the correction factor from Table 3 of Skaggs)
For full Wind combinations
M2 k2 (V ^2 (2 Sf qww)) (Skaggs Eqn 5)
M2 1 13 916 42 lb ^2 (2 12 ft 14 320 psf)) 12 in
M2 2,825 68 in -lb
For 1/2 Wind combinations
M2 k2 (V ^2 (2 Sf (qww /2))) (Skaggs Eqn 5)
M2 1 13 458 21 lb ^2 (2 12 ft (14 320 psf /2))) 12 in
M2 1,412 84 in -lb
STEP 7 Calculate Axial Compression Force in Post
Sf is the frame spacing
W width of building feet
S 25 00 psf roof snow load
DT 3 3 psf top chord dead load
DB 1 psf bottom chord dead load
D L W S/2 (IBC)
Page 14 of 31
Pf ((Sf W) 2) ((S 2) DT DB (((3 qwr) qlr) 4))
(H2 (2 W)) ((R mD) (Sf H2 (qlr qwr)))
Pf ((12 ft 32 ft) 2) ((25 00 psf 2) 3 3 psf
1 0 psf (((3 3 922 psf) -13 368 psf) 4)) (5 33 ft
(2 32 ft)) 2,869 00 lb 0 96 (12 ft 5 33 ft
-13 368 psf 3 922 psf)))
3,048 09 lb
D L S W /2 (IBC
Pf ((Sf W) 2) (S DT DB (((3 (qwr /2)) (qlr /2)) 4))
(H2 (2 W)) ((R mD) (Sf H2 ((qlr /2) (qwr /2))))
Pf ((12 ft 32 ft) 2) ((25 00 psf 2) 3 3 psf
1 0 psf (((3 3 922 /2 psf) -13 368 /2 psf) 4)) (5 33 ft
(2 32 ft)) 2,869 00 lb 0 96 (12 ft 5 33 ft
-13 368 /2 psf 3 922 /2 psf)))
5,750 00 lb
Page 15 of 31
NOTE It was found that Deadload Snowload windload /2 controlled both
the groundline moment adequacy and post adequacy in the positive
moment region
STEP 8 Check Post Adequacy at Groundline
fc Pf A
A b d
A 6 in 8 in 48 00 in ^2
D L W S/2 (IBC)
fc 63 50 psi 3 048 09 lb 48 00 in ^2
D L S W /2 (IBC)
fc 119 79 psi 5,750 00 lb 48 00 in ^2
The allowable compressive stress in the post is given by
Fc Fc (CD CM CF CP CI) (NDS Table 2 3 1 p 9)
Fc 850 psi actual compression stress parallel -to -grain
(NDS Supp Table 4D, p 39) See Hem -Fir
CD the load duration factor for wind of 1 6 (NDS Table 2 3 2) 1997 UBC
2316 Table 2 3 2 footnote 2 provides, 1 6 may be used for members
and nailed and bolted connections exhibiting Mode III or IV behavior,
except that the increases for wind are not combined with the increase
allowed in Section 1612 3 The 60- percent increase shall not apply to
the allowable shear values in Tables 23 -II -H, 23- II,I -1 23- II -I -2,
23 -II J or in Section 2315 3
Since the post will be subjected to wet conditions at and below the
groundline, we choose
Page 16 of 31
CM (Wet service factor) 0 91 (NDS Supp Table 4D, p 37)
CF 1 (NDS Supp Table 4D p 37)
Since the column is laterally supported from all sides at the groundline,
the column stability factor is
CP 1 (NDS 3 7 1 1 p 22)
CI 0 85 (NDS Table 2 3 1 1 p 11)
F'c 1051 96 psi 850 psi 1 6 1 0 91 1 0 85
Using the full bending moment at groundline the bending stress in the post
is given by
Fbl Ml S
S 64 00 in ^3
For full Wind combinations
Fbl 729 37 psi 29,670 04 in -lb 64 00 in ^3
For 1/2 Wind combinations
Fbl 364 68 psi 21 249 96 in -lb 64 00 in ^3
The allowable bending stress is given by
Fb' Fb (CD CM CL CF CI CR) (NDS Table 2 3 1 p 9)
Fb 975 psi (NDS Supp Table 4D p 39) See Hem -Fir
CD 1 6 (IBC)
Cm 1 (NDS Supp Table 4D p 37)
Cfu 1 (NDS Supp Table 4D p 37)
Cr 1 (NDS Supp Table 4C p 34)
CL 1 (NDS 3 3 3 1, p 16)
CF 1 (NDS Supp Table 4D, p 37)
CI 0 85 (NDS Table 2 3 1 1, p 11)
Fb 975 psi 1 6 1 1 1 0 85 1 1 1326 psi
The interaction equation for checking bending about one axis and
compression is
CSI (Fc F c) ^2 (Fbl (F b (1 (Fc FcE)))) 1 0
(NDS Eqn 3 9 -3 p 23)
For a laterally supported beam column that is restrained from buckling
and twisting the interaction equation can be written as follows
CSI1 (Fc F'C) ^2 Fbl F b =1
D L W S/2 (IBC)
CSI1 63 50 psi 1051 96 psi) ^2) 729 37 psi 1326 psi)
CSI1 0 004 0 55 0 55 1
D L S W /2 (IBC)
CSI1 119 79 psi 1051 96 psi) ^2) 364 68 psi 1326 psi)
CSI1 0 013 0 28 0 29 1
STEP 9 Check Post Adequacy at Positive Moment Region
Fc Pf A
A b d
D L W S/2 (IBC)
fc 63 50 psi 3 048 09 lb 48 00 in ^2
D L S W /2 (IBC)
fc 119 79 psi 5 750 00 lb 48 00 in ^2
Page 17 of 31
The allowable compressive stress is given by
Fc Fc (CD CP CM CI CT CF) (NDS Table 2 3 1 p 9)
Fc 850 psi (NDS Supp Table 4D, p 39)
CD 1 6
To calculate the column stability factor CP, we begin by determining
the effective column length
Le Ke 1 (NDS 3 7 1 2 p 22)
Ke buckling length coefficient for compression members 0 8 for a
propped cantilever
le 126 8 in 0 8 158 5 in
Fc FcE
119 79 psi 1474 79 psi
Fc* Fc(CD CM Ct CF CI)
Fc* 1156 psi 850 psi 1 6 1 0 1 0 85
Cp ((1 (FCE Fc (2 c))
SQR(((1 (FCE Fc (2 c)) ^2
((FCE Fc* psi) c))
Cp ((1 (1474 79 psi 1156 psi)) (2 0 8))
SQR(((1 (1474 79 psi 1156 psi)) (2 0 8)) ^2
((1474 79 psi 1156 psi) 0 8))
0 768
Page 18 of 31
KcE 0 3 for visually graded lumber (NDS 3 7 1 5 p 22)
c= 0 8 for sawn lumber (NDS 3 7 1 5 p 22)
E E CI
CI 0 95 (NDS Table 2 3 1 1, p 11)
E 1300000 psi 0 95 1235000 psi (NDS Supp Table 4D p 39) See Hem -Fir
FcE (KcE E) (Le d)"2 (NDS 3 7 1 5 p 22)
FcE 1474 79 psi (0 3 1235000 psi) (158 5 in 8 in) ^2
To use Eqn 3 9 -3 in the NDS the values must satisfy the following equation
(NDS 3 9 2, p 23)
(NDS 3 7 1 5, p 22)
(NDS 3 7 1 5 p 22)
CI 0 85 (NDS Table 2 3 1 1, p 11)
F c 804 0870551 psi 850 psi 1 6 0 768 0 85 1
Calculating the bending stress in the positive moment region
For full Wind combinations
Fb2 44 15 psi 2,825 68 in -lb 64 00 in ^3
For 1/2 Wind combinations
Fb2 22 08 psi 1,412 84 in -lb 64 00 in ^3
The allowable stress is given by
Fb Fb (CD CL CI CF CFU CM) (NDS Table 2 3 1, p 9)
Fb 975 psi (NDS Supp Table 4D p 39) See Hem -Fir
CD 1 6
Page 19 of 31
CI 0 85 (NDS Table 2 3 1 1, p 11)
CL ((1 (FbE Fb 1 9) SQR((((1 (FbE Fb 1 9) ^2)
((FbE Fb 0 95)) (NDS Eqn 3 3 3 1 p 16)
Lu Ke 1 (NDS 3 7 1 2, p 22)
Lu 126 80 in 0 8 158 5 in
le 233 31 in 1 84 126 80 in (NDS Table 3 3 3 p 17)
RB SQR(Le d) b ^2 (NDS Eqn 3 3 -5 p 16)
RB 0 99 SQR(( 233 31 in 8 in) 6 in ^2)
FbE (KbE E) RB ^2
KbE 439 Euler buckling coefficient for beams
FBE 554,137 10 psi (0 439 1235000 psi) 0 99 in ^2
Fb' Fb CD CI CM CF)
Fb 1 326 00 psi 975 psi 1 6 0 85 1 1
CL 1 000 (NDS 3 3 3 1, p 16)
CM 1
CF 1 (NDS Supp Table 4D, p 37)
Cfu 1 (NDS Supp Table 4D p 37)
Fbl' 1 325 84 psi 975 psi 1 6 1 000 0 85 1 1 1 1
The interaction applies again
CSI2 (Fc F C) ^2 Fbl F b =1 (NDS Eqn 3 9 -3, p 23)
D L W S/2
CSI2 0 11 =1
D L S W /2
CSI2 0 08 =1
Bond Strength Of Concrete -To -Wood (Hoyle Woeste, p 335 -336)
The direct bearing capacity under vertical load depends on the bearing
capacity of the soil against the end of the post and the frictional
resistance between the post and the soil, without producing much end
Page 20 of 31
bearing pressure at the butt Interestingly it has been determined
that firm backfilling of the hole with compacted soil, sand soil
concrete or concrete is a more effective way of increasing vertical
force resistance than placing mats of footings of concrete beneath the
butt ends Concrete encasement of the post in the ground contact area
enlarges the friction surface and can generally be credited with a wood
to concrete bond strength of 30 psi
Strength ((b in 2) (d in 2)) embed in 30 psi
33600 lb ((6 in 2) (8 in 2)) 40 00 in 30 psi
25 00 psf 3 3 psf 1 psf) 30 ft /2 5 14 12 ft 6465 6 lb
6465 6 lb 33600 lb
Therefore no concrete footing pad is required below columns
FOUNDATION UPLIFT
From ASAE EP486 the following equation calculates the soil uplift
resistance of a 32 004 in deep post with a concrete collar 26 in thick
x 24 in diameter (Walker Woeste p 163)
The presumed type 4 soil has a soil friction angle 26 degrees and density
85 lb /ft ^3 (Walker Woeste Appendix E Table 1 p 340)
a soil density
85 lb /ft ^3 (Walker Woeste Appendix E Table 1 p 340)
C concrete density
150 lb /ft ^3 (Walker Woeste p 163)
G gravity acceleration constant
1 0 lbf /lb
d embedment depth
40 00 in
t collar thickness
31 in
w collar width
24 in
Phi soil friction angle
26 degrees (Walker Woeste, Append E, Table 1 p 340)
Ap post cross sectional area
6 in 8 in
48 00 in ^2
h thickness of attached concrete (depth of collar)
31 in
d d h
then
U soil and foundation uplift resistance (in lb)
a 3 14 (d [w ^2 d w tan(Phi) d ^2 (3 tan(Phi)] d' Ap
85 3 14 ((9 00 [24 ^2 9 00 24 tan(26) 9 00 ^2 (3 tan(26)
9 00 48
5,254 67 lb
Constant Value
Uplift (TrussSpan Sidewall overhangs) Sidewall) 2)
{PSCCBLoad [((3 QWR) QLR) /4] H2 2 /TrussSpan 2
(QLR QWR)} (Bender Woeste, p 56)
-(32 ft 0 ft)* 12 ft) /2) (2 313 psf [((3 -3 922 psf)
-13 368 psf) /4] 5 33 ft 2/ 32 ft 2 -13 368 psf
(3 922 psf)1}
2003 44 lb
5,254 67 lb 2003 44 lb
Therefore collar is sufficient to resist uplift
The normal duration uplift (for truss -to- column 'connections) is
Load 2003 44 lb 1 6 1252 15 lb
BOLTS Design Values for Single Shear Connections (NDS Sec 8 2, p 53)
Page 21 of 31
Page 22 of 31
Wood -to -Wood Connections (NDS, 8 2 1)
Mode Im
Z (D Tm Fem) (4 KTheta)
1760 (0 625 in 6 2250 psi) (4 1 1988) (NDS, Eq 8 2 -1)
Mode Is
Z (D Ts Fes) (4 KTheta)
789 (0 625 in 2 75 in 2200 psi) (4 1 1988) (NDS Eq 8 2 -2)
Mode II
Z (K1 D Ts Fes) (3 6 KTheta)
2138 (2 440 0 625 in 2 75 in 2200 psi) (3 6 1 1988)
(NDS, Eq 8 2 -3)
Mode IIIm
Z (K2 D Tm Fem) (3 2 (1 (2 Re)) KTheta)
807 (1 118 0 625 in 6 in 2250 psi) (3 2 (1 (2 1 023))
1 1988)
(NDS Eq 8 2 -4)
(Note when a mode N/A the mode is not applicable
Mode IIIs
Z (K3 D Ts Fes) (3 2 (2 Re) KTheta)
486 (1 457 0 625 in 3 in 2200 psi) (3 2 (2 1 023) 1 1988)
(NDS Eq 8 2 -5)
Mode IV
Z (D (3 2 KTheta)) Sgr((2 Fem Fyb) (3 (1 Re)))
588 (0 625 in (3 2 1 1988)) Sgr((2 2250 psi 45000 psi) (3 (1
1 023)))
(NDS, Eq 8 2 -6)
Where
Kl ((Sqr(Re ((2 (Re 2)) (1 Rt Rt 2)) ((Rt 2)
(Re 3))))- (Re (1 Rt))) (1 Re)
2 440 ((Sqr(1 023 ((2 (1 023 2)) (1 2 18 2 18 2))
((2 18 2) (2 18 3)))) (1 023 (1 2 18))) (1 1 023)
(NDS 8 2 1)
K2 -1 Sqr((2 (1 Re)) (((2 Fyb) (1 (2 Re)) D 2)
(3 Fem (Tm 2))))
1 118 -1 Sgr((2 (1 1 023 (((2 45000 psi) (1 (2 1 023
0 625 in 2) (3 2250 psi (6 2))))
(NDS 8 2 1)
K3 -1 Sgr(((2 (1 Re)) Re)
(((2 Fyb) (2 Re) D 2) (3 Fem (Ts 2))))
1 457 -1 Sgr(((2 (1 1 023 1 023 (((2 45000 psi) (2 1 023
0 625 in 2) (3 2250 psi (2 75 2))))
(NDS 8 2 1)
Re Fem Fes (NDS 8 2 1)
1 023 2250 psi 2200 psi
Rt Tm Ts (NDS 8 2 1)
2 18 6 in 2 75 in
Tm Thickness of main (thicker) member inches
6 in
Ts Thickness of side (thinner) member, inches
2 75 in
Fem Dowel bearing strength of the main (thicker) member, psi
2250 psi (See NDS Table 8A p 53, Using Spruce -Pine Fir)
Fes Dowel bearing strength of the side (thinner) member, psi
2200 psi (See NDS Table 8A p 53 Using Spruce -Pine Fir)
Fyb Bending yield strength of bolt, psi
45000 psi
D nominal bolt diameter inches
0 625 in
KTheta 1 (ThetaMax 360)
1 1988 1 (71 57 360)
ThetaMax maximum angle of load to grain (0 Theta 90) for any
member in a connection
71 57
therefore
Z 486 lb
Load 2003 44 lb 1 6 1252 15 lb
1252 15 lb 486 lb 2 577 bolts 3 bolts
Page 23 of 31
Therefore use (3) 5/8 bolts thru
(NDS eq 12 3 -2)
Note Minimum edge end and on center spacings of 2 -1/2 must be maintained
ALTERNATE
The nominal nail or spike lateral design values, Z, shall be the lesser of
Mode Is
Z D ts Fes KD (NDS eq 12 3 -1)
where D nail or spike diameter, inches 0 177 inch
where ts thickness of side member in inches 2 75 in
where Fes dowel bearing strength of side member 3350 psi for HF
(NDS Table 12A)
where KD 10D 0 5 for 0 17 in D 0 25 in
KD 2 27 (10 0 177 0 177 in) 0 5
Z 718 33 lb 0 177 in 2 75 in 3350 psi 2 27
Mode IIIm
Z k1 D p Fem KD (1 2 Re)
where kl -1 SQR( 2 (1 Re) (2 Fyb (1 2 Re)
D ^2 3 Fem P ^2))
where Re Fem Fes
Where Fem dowel bearing strength of main member (member holding point)
Page 24 of 31
3350 psi for HemFir (NDS Table 12A)
Re 1 045 3500 3350
Where Fyb bending yield strength of nail of spike 115 000 psi
for 0 177 diameter threaded hardened -steel nails (NDS Table 12 3C fn 2)
where p penetration of nail or spike in main member 2 25 in
K1 1 123 -1 SQR(2 (1 1 045) (2 115 000 psi (1 2
1 045) 0 177 in ^2 /(3 3500 psi in ^2)))
Z 223 25 lb 1 123 0 177 in 2 in 3500 psi 2 27 (1 2 1 045)
Mode IIIs
Z k2 D ts Fem KD (2 Re)
where k2 -1 SQR((2 (1 Re) Re) (2 Fyb 2 Re)
D ^2 3 Fem is ^2))
K2 1 047 -1 SQR ((2 (1 1 045) 1 045) (2 115,000 psi
(2 1 045) 0 177 in ^2 (3 3500 psi 2 75 in ^2)))
Z 258 09 lb 1 047 0 177 in 2 75 in 3500 psi (2 27 (2 1 045)
Mode IV
Z (D ^2 KD) SQR((2 Fem Fyb) (3 (1 Re)))
Z 158 10 lb (0 177 in ^2 2 27) SQR((2 3500 psi 115,000 psi)
(3 (1 1 045)))
Mode IV governs, therefore Z 158 lb
Z' Z CD CM Ct Cd Ceg Cdi Ctn
CD 1 6
CM 1 0 for wood used in continuously dry conditions (NDS 7 3 3)
Ct 1 0 for wood which will not experience sustained exposure to
temperatures over 100 degrees F
Cd 1 00 p (12 D) 1 0 2 in (12 0 177 in)
Ceg does not apply nails not driven in the end grain
Cdi 1 0 for nails used in diaphragm construction
Ctn does not apply, not a toe nailed connection
NOTE For ease of application CD is applied to the load
Z 158 10 lb 158 lb 1 0 1 0 1 00* 1 0
Calculate required number of nails
Load 2003 44 lb 1 6 1252 15 lb
1252 15 lb 486 lb 158 10 lb /nail 4 846 nails 5 nails
(NDS Eq 12 3 -4)
(NDS Eq 12 3 -5)
(NDS 12 3 5)
(NDS 12 3 6)
Page 25 of 31
Therefore, use (1) 5/8 in bolt through plus 5 40d threaded hardened nail
According to NDS p 27 paragraph 7 1 1 1 'mixed fastener connections shall
be based on tests or other analysis (see 1 1 1 4) In completing the
previous design, we added a bolt allowable value to nail values Based upon
our experience with truss uplift at post connections such designs have
performed satisfactorily and thereby meet the requirements of the NDS
Sidewall Embedment
Determine the required column embedment
h Base moment V
h 2 70 in 29 670 04 ft -lb 916 42 lb) 12 inches
S1 Column Depth Lateral Soil Bearing Pressure 2 3
S1 333 33 lb 3 333 ft 2000 lb -ft 2 3
The Lateral Soil Bearing values may be increased the amount of the
designated value for each additional foot of depth to a maximum of
15 times the designated value Isolated poles for uses such as
poles used to support buildings that are not adversely affected by a
1/2 -inch motion at ground surface due to short -term lateral loads may
be designed using lateral bearing values equal to two times the
tabulated values
Additionally, an increase of one third shall be permitted when considering
load combinations, including wind or earthquake loads, as permitted by
2
A (2 34 P) (S1 diameter)
A 2 490 (2 34 916 42 in -lb) (333 33 lb 2 00)
d (A 2) (1 Sqr(1 ((4 36 h) A))
d 4 501ft (2 490 2) (1 SQR(1 ((4 36 3 333 ft) 2 490
Therefore Depth (d) 3 333 ft is adequate to withstand lateral loads
Determine the required diameter of the concrete column encasement
The allowable foundation pressure may be increased 20 percent for each
additional foot of width or depth (beyond one foot) to a maximum value
of 3 times the designated value
No increase for width is allowed for 1000 psf soil
AFP 3,333 33 psf 2000 psf (1 ((3 333 ft 1 ft) 20
((2 00 ft 1) 20
Load carrying capacity AFP PI r ^2
10 472 00 lbs 3 333 33 psf 3 1416 1 00 ft 2
Load on Footing (S DT DB) W 2 Sf
6,045 60 lbs (25 00 psf 3 3 psf 1 0 psf) 32 ft 2 (12 ft 2)
6,045 60 lbs 10 472 00 lbs
Therefore Diameter 24 in
Page 26 of 31
Embed 3 333 feet (40 00 in) deep in 2 58 foot (31 in) concrete
backfill with 24 in diameter
6 x 8 Rough HEM -FIR1 Sidewall columns are required
These columns are basically only subject to the wind load They are
supported at least at the roof line, but we will also support them at the
truss bottom chord line and use these braces for stabilizing the roof
trusses against wind uplift They also are embedded below grade in pole
footings Consider them as propped cantilevers (Barbera p 13)
Endwall Design Column Spacings 12 12
Eave Height 14 ft (168 in)
Overall heel height of roof truss at eave line 6 in
Unsupported length of column 126 8 in
BENDING
ENDWALL WIND COLUMN DESIGN
Page 27 of 31
P 14 320 psf
W 14 320 psf (1 ft ^2 144 in ^2) ((12 ft 12 ft) 2 12 in)
8 077 pli
Mmax wL ^2 8
8 077 pli 126 8 in ^2 8
16232 838 in -lbs
SM (W (D 2)) 6 (NDS 3 3 2 2 eqn 3 3 -4, p 16)
SM (6 in (6 in 2)) 6
SM 36 00 in A3
Fb Mmax SM
16232 838 in -lbs 36 00 in ^3
450 912 psi
Fb' Fb (CD CL CF Cfu CI) (NDS Table 2 3 1, p 9)
CD 1 6 (UBC Section 2316 2, Amend 6 fn 2 p 2 -291)
CL (beam stability factor) 1 0 (NDS 3 3 3 1 p 16)
CF 1
Page 28 of 31
Cfu 1 00 (NDS Supp Table 4D, p 39)
CI 0 85 (NDS Table 2 3 1 1, p 11)
Fb 575 psi 1 6 1 1 00 1 0 85 782 psi
450 912 psi 782 psi, therefore wind load checks ok
6 x 6 Rough Hem -Fir #2 Endwall columns are required
Endwall Truss to Column Calculations
Raw Nails
PSCCBLoad Steel Weight CCB Weight Purlin Weight Truss Weight
0 723 0 12 0 767 0 7
PSCCBLoad 2 31 psf
Qwr 3 922 psf
Qlr -13 368 psf
Sidewall 12 ft on center
TrussSpan 32
Total
DOL 1 6
Uplift (TrussSpan Sidewall overhangs) 2) Sidewall /2)
Endwall overhang)) PSCCBLoad [((3 -QWR) QLR) /4]
H2 ^2 /TrussSpan ^2 -QLR -QWR)}
Uplift -(32 ft 0 ft) 2) ((12 ft /2) 0 ft))
{2 31 psf [((3 -3 922 psf) -13 368 psf) /4]
5 33 ft ^2/ 32 ft ^2 -13 368 psf -(3 922 psf)} 640 95 lb
The nominal nail or spike lateral design values, Z shall be the lesser of
Mode Is
Z D ts Fes KD (NDS eq 12 3 -1)
where D nail or spike diameter, inches 0 148 inch
where ts thickness of side member in inches 1 5 in
where Fes dowel bearing strength of side member 3500 psi for SPF
(NDS Table 12A)
where KD 2 20 for D 0 17 in
Z 353 18 lb 0 148 in 1 5 in 3500 psi 2 20
Mode IIIm
Z k1 D p Fem KD (1 2 Re) (NDS eq 12 3-2)
where kl -1 SQR( 2 (1 Re) (2 Fyb (1 2 Re)
D ^2 3 Fem P ^2))
where Re Fem Fes
Where Fem dowel bearing strength of main member (member holding point)
3500 psi for HemFir (NDS Table 12A)
Re 1 000 3500 3500
Where Fyb bending yield strength of nail of spike 115,000 psi
for 0 148 diameter threaded hardened -steel nails (NDS Table 12 3C fn 2)
where p penetration of nail or spike in main member 1 5 in
K1 1 154 -1 SQR(2 (1 1 000) (2 115 000 psi (1 2
1 000) 0 148 in ^2 (3 3500 psi 1 5 in ^2)))
Z 135 86 lb 1 154 0 148 in 1 5 in 3500 psi 2 20 (1 2 1 000)
Mode IIIs
Z k2 D is Fem KD (2 Re)
where k2 -1 SQR((2 (1 Re) Re) (2 Fyb 2 Re)
D ^2 3 Fem is ^2))
K2 1 154 -1 SQR ((2 (1 1 000) 1 000) (2 115 000 psi
(2 1 000) 0 148 in ^2 (3 3500 psi 1 5 in ^2)))
Z 135 86 lb 1 154 0 148 in 1 5 in 3500 psi 2 20 (2 1 000)
Mode IV
Z (D ^2 KD) SQR((2 Fem Fyb) (3 (1 Re)))
(NDS Eq 12 3 -4)
Z 115 32 lb (0 148 in ^2 2 20) SQR((2 3500 psi 115 000 psi)
(3 (1 1 000)))
Therefore Z 184 52 lb
CM 1 0 for wood used in continuously dry conditions (NDS 7 3 3)
Ct 1 0 for wood which will not experience sustained exposure to
Page 29 of 31
Page 30 of 31
temperatures over 100 degrees F
Cd 0 84 p (12 D) 1 0 1 5 in (12 0 148 in)
(NDS Eq 12 3 -5)
Ceg does not apply, nails not driven in the end grain
Cdi 1 0 for nails not used in diaphragm construction
Ctn does not apply, not a toe nailed connection
Z 155 84 lb 100 89 lb 1 6 1 0 1 0 8446 1 1
Calculate required number of nails
400 60 lb 155 84 lb /nail 2 57 nails 3 nails
Therefore, use 3 10d commons
(NDS 12 3 5)
(NDS 12 3 6)
WARNING Added insulation, ceiling materials, lighting and HVAC equipment or
other loads imposed
upon the roof system BEYOND those stated above will reduce the overall capacity
of the structure and
its ability to resist the required design snow loads
Sources
Alumax Building Products 1992 Diaphragm Loading On Roofs and End Wall
Sections Alumax Building Products Testing Laboratories Perris
California
American Forest and Paper Association 1997 ANSI /AF &PA NDS -1997
National Design Specification for Wood Construction AF &PA,
Washington D C
American Lumber Standards Committee (ALSC) December 1999 Woodwords,
pg 41
Bender DA TD Skaggs, and F E Woeste 1990 Rigid Roof Design
for Post -Frame Buildings Paper #90 -4525 ASAE St Joseph MI
49085 -9659 1991 Applied Engineering in Agriculture 7(6) 755 -760
1991 Frame Building Professional 3 (6) 4 -11 30 -33
Bender DA TD Skaggs and F E Woeste 1992 Design of Side -Wall
Posts in Post -Frame Buildings Paper #92 -4541 ASAE St Joseph, MI
49085 -9659 referred to as Skaggs et al Also published in Frame
Building News, March 1993 Applied Engineering in Agriculture 9(2)
253 -259
Hoyle, R J and F E Woeste 1989 Wood Technology in the Design of
Structures Iowa State University Press Ames Iowa
International Conference of Building Officials (ICBO) 1997 Uniform
Building Code ICBO Whittier, CA
National Forest Products Association (NFPA) 1991 National Design
Specification (NDS) for Wood Construction Washington DC NFPA
USP Full Line Catalog Construction Hardware 1996 United Steel Products
Products Company, Inc Silver Metal Products, Inc
Pollock DG DA Bender and K G Gebremedhin 1996 Designing for
chord forces in post -frame roof diaphragms Frame Building News
Page 31 of 31
8 (5) 40 -44
Taylor, Steven E 1996 Earthquake considerations in post -frame building
design Frame Building News 9(1) 62 .1
Townsend Merl 1992 Diaphragm Loading on Roofs and End Wall Sections
Alumax Building Products Inc Perris Valley, CA
Uniform Building Code (UBC) 1997 International Conference of Building
Officials (ICBO) Whittier CA
Walker, John N Frank E Woeste 1992 Post -Frame Building Design
American Society of Agricultural Engineers