BASE PLATE/BOLT CHECK - USER'S GUIDE - rev1 As part of standard pipe support allowable load calculations, support base or end plate as well as anchor bolts, should be designed so a s to resist tension, shear, and bending experienced by the support itself. This program is created to check adequacy of a given base plate details based on the ca lculated reactions to the base or end plate. (Note: Input required on all green boxes)
1. PARAMETERS:
1. Select Anchor Bolt 2. Input base plate dimension B 3. Input base plate dimension D 4. Input base plate dimension C 5. Input base plate thickness 6. Input no. of bolts at tension side 7. Input bolt hole diameter 8. Select Member Size (Structural Steel Shapes) 9. Input base plate loads (reactions) 10. Input allowable stresses for plate and bolting materials Ft=Allowable stress in tension for anchor bolt Fv=allowable stress in shear for anchor bolt f'c=allowable compressive stress of concrete (default is 20.8 Mpa) Fb=allowable bending stress of plate (Fb=Fy/1.5 where Fy=Yield Stress)
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11. Obtain value of Xn/d from the graph below. Use values of x/d and P to obtain this value.
Stress calculations are done automatically. For Bending Stress c heck of the base plate, whenever allowable bending stress is not sa tisfied, program calculates "recommended thicknesss" of the plate.
Rev 0 1
Date 20-Jan-06 01-Feb-06
2
BASE PLATE CALCULATION PROCEDURE Parameters: B, D: C: t: Nb: do: Ab: dt: d: u: g: R:
base plate dimensions center to center distance between outer bolt holes Q base plate thickness no. of holes at tension side effective outside diameter of anchor bolts area of bolt distance of outer bolt hole to the edge of the plate effective depth of the plate distance from the flange face of dt the column to the edge of the plate distance from the flange face of the column to the outer bolt hole C bolt hole diameter
Mx u
N g
t
R
d
B
B=D Allowable Stress: Fb = 157 Mpa (Allowable bending stress of the plate, Fb = Fy/1.5) Ft = 120 Mpa (Allowable tension stress of anchor bolt) Fv = 70 Mpa (Allowable Shear Stress of Anchor bolt) Fy = 235 Mpa (Yield Strength of JIS SS 400)
Effective Anchor Bolt Diameter (db): Anchor db Bolt (mm) M16 14.701 M20 18.376 M22 20.376 M24 22.051 M27 25.051 Strength of Expansion Anchor Bolt : Anchor Size Allow Load (KN) Bolt (in) Tension Shear M16 5/8 26.7 41.2 M20 3/4 38.9 60 M22 7/8 43 79.8 M24 1 39.7 117.5 M27 1 1/4 95.5 181.6 The values listed above are ultimate load capacities in kiloNewtons for carbon steel and stainless steel power stud which should be reduced by a minimum safety factor of 4 to determine the allowable working load. Strength of concrete is f'c = 2000psi
2
3
Design Procedure Calculate e (load eccentricity): e = Mx/N If e > D/6 + dt/3, tension governs on base plate Calculate x/d ratio: x/d = (e - 0.5D)/(D-dt) Calculate P: P = (Ab x Nb)/(BXd) Given the values of x/d and P, obtain value of Xn/d from the graph below:
Calculate Xn: Xn = (Xn/d) x d
Anchor Bolt Check:
When Expansion Anchor Bolt is required:
1. Check at tension: ft ≤ Ft, Ft = 120 Mpa ft = T/Ab T = Z/Nb Z = N*(e-0.5D+xn/3) / (D-dt-xn/3)
1. Check at tension, T ≤ Tallow 2. Check at shear, Q ≤ Qallow Note: Refer to allowable loads of Expansion Anchor Bolts above.
2. Check at Shear: fv ≤ Fv, Fv = 70 Mpa fv = Q/Ab 3. Check at Combined Tension and Shear: 1.4fto - 1.6fv = fts; fts ≤ fto note: fto = Ft therefore, fts = 1.4Ft - 1.6fv ≤ Ft
4
Base Plate Check: u g
σc
Xn g
R+2g
Check Compressive Strength: σc ≤ f'c, f'c = 20.8 Mpa (to be decided by Civil) σc=２*N*(e+0.5D-dt) / {D*xn*(D-dt-xn/3)} Check Bending Stress: fb ≤ Fb, Fb = 157 Mpa fb = 3σc(u/t) [1-(u/3Xn)] ; if fb > Fb, calculate required thickness, treq 0.5 treq = u * { 3*σc / fb’ * (1 – u/(3xn))} Check Bending Stress due to Anchor Bolt Tensile Force fb ≤ Fb, Fb = 157 Mpa fb＝Ｍ／Ｚ M=Txg Z=1/6x(R + 2g) x t
Rev
Date 0
20-Jan-06
1 01-Feb-06
5
BASE PLATE / BOLT CHECK
INPUT REQUIRED ON ALL "GREEN" BOX.
MEMBER:
M16 ANCHOR BOLT 5/8 ANCHOR BOLT SIZE (in)
A6 Ft= Fv= f'c= Fb=
u
1. PARAMETERS: B= 260 D= 260 C= 180 t= 12 Nb= 2 do= 14.701 Ab= 169.74 dt= 40 d= 220 u= 97.5 G= 57.5 R= 19
N mm mm mm mm pcs mm 2 mm mm mm mm mm mm
Q Z
G
Mpa Mpa Mpa Mpa
t Check tension at bolt:
R
Ｍx
Check shear at bolt: Check tension at expansion bolt:
dt
Check shear at expansion bolt: Check compressive strength of concrete:
C□
d
B
Check Bending Stress: ｱﾝｶｰﾎﾞﾙﾄの引張力による底板曲げ応力
BASE PLATE LOADING: 4,513 N N= 2,158 N Q= 3,379,355 N.mm Mx=
D□
eccentricity e=Mx/N 748.80 5 mm if e>(D/6)+(dt/3), base plate is under tension. (D/6)+(dt/3)= 56.666667 (plate is under tension) Calculation for Xn: x = e-0.5D = 618.805 mm x/d = 2.8 obtain value of Xn/d ratio from Graph. P=(Ab x Nb)/(B x d) 0.006 0.350 , therefore Xn/d Xn = 77.0 2. BOLT/EXPANSION BOLT CHECK Check tension at bolt: 44.1 Mpa 92.9 Mpa ft＝Ｔ／Ａb＝ ≦ T = Z/Nb = 7483.2727 N Z = N*(e-0.5D+xn/3) / (D-dt-xn/3) = 14,966.5 N Check shear at bolt: fv= Q / Ab =
120 70 20.8 157
3.2 Mpa
Combined Stresses (Tension and Shear): fts = 1.4fto - 1.6t = 92.9 Mpa fts ≦ fto fto = Ft
Judge OK
≦
70 Mpa
OK
≦
120 Mpa
OK
Check tension at expansion bolt (if required): M16 T= 7,483.3 N
≦
6,675.0 N
NG
Check shear at expansion bolt (if required): M16 Q= 539.5 N
≦
10,300.0 N
OK
3. BASE PLATE CHECK Check compressive strength of concrete: σc = ２*N*(e+0.5D-dt) / {D*xn*(D-dt-xn/3)} 1.95 Mpa σc= Check Bending Stress: 2 fb = 3σc(u/t) [1-(u/3Xn)] fb= 222.7 Mpa
≦
20.8 Mpa
≦
157 Mpa required t
Check Bending Stress due to anchor bolt tensile force: fb＝Ｍ／Ｚ＝ 133.8 Mpa ≦ M=TxG= 430,288.2 N.mm 2 3 Z=1/6x(R + 2G)xt = 3,216.0 mm
157 Mpa
OK
NG 24.7
mm
OK
allowable stress for tension on bolt allowable stress for shear on bolt allowable compressive stress of concrete at 28 days allowable bending stress on plate
0.474 0.045 1.121 0.052 0.094 1.419 0.852
OK OK NG OK OK NG OK
BASE PLATE / BOLT CHECK
INPUT REQUIRED ON ALL "GREEN" BOX.
MEMBER:
M22 ANCHOR BOLT 7/8 ANCHOR BOLT SIZE (in)
16 σt= fv= f'c= fb=
u
1. PARAMETERS: B= 500 D= 500 C= 440 t= 19 Nb= 2 do= 20.376 Ab= 326.08 dt= 30 d= 470 u= 46.8 G= 16.8 R= 26
N mm mm mm mm pcs mm 2 mm mm mm mm mm mm
Q Z
G
t Ｍx
Check shear at bolt: Check tension at expansion bolt:
dt
Check shear at expansion bolt: Check compressive strength of concrete:
C□
d
B
Check Bending Stress: ｱﾝｶｰﾎﾞﾙﾄの引張力による底板曲げ応力
D□
eccentricity e=Mx/N 750.000 mm if e>(D/6)+(dt/3), base plate is under tension. (D/6)+(dt/3)= 93.333333 (plate is under tension) Calculation for Xn: x = e-0.5D = 500.000 mm x/d = 1.1 obtain value of Xn/d ratio from Graph. P=(Ab x Nb)/(B x d)= 0.003 0.320 , therefore Xn/d Xn = 150.4 2. BOLT/EXPANSION BOLT CHECK Check tension at bolt: ft＝Ｔ／Ａb＝ 82.7 Mpa 82.9 Mpa ≦ T = Z/Nb = 26958.542 N 53,917.1 N Z = N*(e-0.5D+xn/3) / (D-dt-xn/3) = 9.5 Mpa
Combined Stresses (Tension and Shear): fts = 1.4fto - 1.6t = 82.9 Mpa fts ≦ fto fto = Ft
Judge OK
≦
70 Mpa
OK
≦
12 0 Mpa
OK
Check tension at expansion bolt (if required): M22 T= 26,958.5 N
≦
10,750.0 N
NG
Check shear at expansion bolt (if required): M22 Q= 3,086.3 N
≦
19,950.0 N
OK
3. BASE PLATE CHECK Check compressive strength of concrete: σc = ２*N*(e+0.5D-dt) / {D*xn*(D-dt-xn/3)} σc= 2.53 Mpa Check Bending Stress: 2 fb = 3σc(u/t) [1-(u/3Xn)] fb=
Mpa Mpa Mpa Mpa
Check tension at bolt:
R
BASE PLATE LOADING: 41,150 N N= 12,345 N Q= Mx= 30,862,500 N.mm
Check shear at bolt: fv= Q Ab =
120 70 20.8 157
41.2 Mpa
≦
20.8 Mpa
OK
≦
15 7 Mpa
OK
15 7 Mpa
OK
Check Bending Stress due to anchor bolt tensile force: fb＝Ｍ／Ｚ＝ 126.3 Mpa ≦ 452,903.5 N.mm M=TxG= 2 3 Z=1/6x(R + 2G)xt = 3,585.9 mm
allowable stress for tension on bolt allowable stress for shear on bolt allowable compressive stress of concrete at 28 days allowable bending stress on plate
0.998 0.135 2.508 0.155 0.122 0.263 0.804
OK OK NG OK OK OK OK
