|
Page 14 of 14 ! ESR-1917
<br /> Given:
<br /> 17-
<br /> Two '/,inch KB-TZ anchors under A t Taub„ +A AN 1.5h,r
<br /> static tension load as shown.
<br /> hxr= 3.25 in. ._._ _. _._ _
<br /> Normal wt. concrete,f,=3,000 psi 1
<br /> No supplementary reinforcing.
<br /> s=6"
<br /> Assume uncracked concrete. E
<br /> Condition B per ACI 318 D.4.4 c) .... -C�' - - - -
<br /> Calculate the allowable tension load for Lt
<br /> this configuration. �W 1.5her
<br /> 1.5h,( I c=4'
<br /> A-A
<br /> Calculation per ACI 318-02 Appendix D and this report. Code Report
<br /> Ref. Ref.
<br /> Step 1. Calculate steel capacity: ON, =OnA 1, =0.75 x 2.0.101 x 106,000=16,0591b D.5.1.2 Table 3
<br /> Check whether fx is not greater than 1.9fa and 125,000 psi. D.4.4 a)
<br /> Step 3. Calculate concrete breakout strength of anchor in tension:
<br /> §4.1.2
<br /> N,.� _-vC V,,,Nwed,Nwc,Nwcp,NNb D.5.2.1 §4.1.3
<br /> NCO
<br /> Step 3a. Verify minimum member thickness,spacing and edge distance: D.8 Table 3
<br /> h,,,,,=6 in.56 in. .:ok 2.375,5.75 Fig.4
<br /> slo e= 2.375-5.75 =_3.0
<br /> p 3.5-2.375
<br /> For cm;n =4 in 3.5,2.375
<br /> 2.375 controls
<br /> S.0 =5.75-[(2.375-4.0)(-3.0)]=0.875<2.375in<6in:.ok 0.875 c,
<br /> 4
<br /> Step 3b. For AH check 1.5hd =1.5(3.25)=4.88 in>C 3.0ha, =3(3.25)=9.75 in>s Table 3
<br /> D.5.2.1
<br /> Step 3c. Calculate Am and AN for the anchorage: A. =9h" =9 x(3.25)' =95.1 in'
<br /> D.5.2.1 Table 3
<br /> A„ =(1.5h„ +c)(3h„ +s)=[1.5x(3.25)+4[3x(3.25)+61=139.8in' <2 A� :.ok
<br /> Step 3d. Determine w,r,N: e,v =0 1 o D.5.2.4 -
<br /> Step 3e. Calculate Nb: Ne =k, Vf7 h� ' =17 x V3,000 x 3.25" =5,456 Ib D.5.2.2 Table 3
<br /> Step 3f. Calculate modification factor for edge distance: wed,,v=0.7+0.3;.5(3.25) -0.95 D.5.2.5 Table 3
<br /> Step 3g. w,,N =1.41 (uncracked concrete) D.5.2.6 Table 3
<br /> c;1.5h,f 4 1.5(3.25)
<br /> Step 3h. Calculate modification factor for splitting: w,.p„v =ma check:7.5 =0.53; 7 5 _-0.65
<br /> §4.1.3
<br /> i.sh,� Table 3
<br /> O.tiS>0.53:.-controls
<br /> C,
<br /> Step 3i. Calculate ON,,�: (DN�,0.65 x 139.8 x 1 00 x 0.95 x 1.41 x 5,456 x 0.65=4,539 Ib D.5.2.1 §4.1.2
<br /> 95.1 D.4.4 c) Table 3
<br /> Step 4. Check pullout strength: Per Table 3, (PnNp.,,rc=0.65x2x5,515 Ib '3po0 =7,852 Ib>4539 .'.OK D.5.3.2 §4.1.5
<br /> J 2600 0.4.4 c) Table 3
<br /> Step 5. Controlling strength: (PNcby=4,539 Ib< mnN n< ONs mN�bg controls D.4.1.2 Table 3
<br /> Step 6. Convert value to ASD: T,,,w„,= A 579 = 3,242 Ib. _ 4.2.
<br /> I.4 §
<br /> FIGURE 6--EXAMPLE CALCULATION
<br />
|