塔吊基礎(chǔ)設(shè)計(jì)(四樁)5510

1、塔吊基礎(chǔ)設(shè)計(jì)(四樁)計(jì)算書工程名稱：華力特大廈編制單位：深圳超卓工程有限公司1.計(jì)算參數(shù)(1)基本參數(shù)采用1臺QZT63A(5510)塔式起重機(jī)，塔身尺寸1.70m,地下室開挖深度為-5.00m；現(xiàn)場地面標(biāo)高 0.00m,承臺面標(biāo)高-1.50m ;采用預(yù)應(yīng)力管樁基礎(chǔ)，地下水位-3.00m。1)塔吊基礎(chǔ)受力情況荷載工況基礎(chǔ)荷載P(kN)M(kN. m)FkFhMMZ工作狀態(tài)950.0030.001600.00340.00非工作狀態(tài)850.0070.001800.000Fk =基礎(chǔ)頂面所受垂直力Fh =基礎(chǔ)頂面所受水平力M =基礎(chǔ)頂面所受傾覆力矩M =基礎(chǔ)所受扭矩塔吊基礎(chǔ)受力示意圖比較樁基礎(chǔ)塔吊的

2、工作狀態(tài)和非工作狀態(tài)的受力情況，塔吊基礎(chǔ)按非工作狀態(tài)計(jì)算如圖Fk=850.00kN,F h=70.00kNM=1800.00+70.00 X 1.4 0=1898.00kN . mFk =850.00X 1.35=1147.50 kN,Fh =70.00 X 1.35=94.50 kNMk=(1800.00+70.00 X 1.40) X 1.35=2562.30kN- m2)樁頂以下巖土力學(xué)資料序 號地層名稱厚度L(m)極限側(cè)阻力標(biāo) 準(zhǔn)值 q§k( kPa極限端阻力標(biāo)準(zhǔn)值 qpk(kPa)qsiki(kN/m)抗拔系數(shù)入i入 i qsiki (kN/m)1砂質(zhì)粘土0.2040.00

3、9000.008.000.403.20樁長0.20Zj qsik* Li8.00Zj 入 i qsik* Li3.203)基礎(chǔ)設(shè)計(jì)主要參數(shù)基礎(chǔ)樁采用 4根。500預(yù)應(yīng)力管樁，樁頂標(biāo)高-2.90m ;樁混凝土等級C25,f c=11.90N/mm2 ,Ec=2.80 X 104N/mm； ft=1.27N/mm2,樁長 0.20m,壁厚 125mm 鋼筋 HRB335 f y=300.00N/mm2,Es=2.00 X 105N/mn2承臺尺寸長(a)=5.00m,寬(b)=5.00m,高(h)=1.50m ;樁中心與承臺中心 2.00m,承臺面標(biāo)高-1.50m；承臺混凝土等級 C35, f t

4、=1.57N/mm2,f c=16.70N/mm2, 丫羥=25kN/m3G=abh 丫 羥=5.00 X 5.00 X 1.50 X 25=937.50 kN2 .樁頂作用效應(yīng)計(jì)算(1)豎向力1)軸心豎向力作用下Z=(Fk + G)/n=(850.00+937.50)/4=446.88kN2)偏心豎向力作用下按照Mx作用在對角線進(jìn)行計(jì)算，M=M=1898.00kN. m yi=2.00 x2 0.5 =2.83mZ =(F k+G)/n ± My" 2 yi2=(850.00+937.50)/4 ±(1898.00 X2.83)/(2 X2.832)=446.8

5、8 ± 335.34Nmax=782.22kN, N kmin=111.54kN (基樁不承受豎向拉力 )(2)水平力Hk =Fh/n=70.00/4=17.50kN3 .單樁允許承載力特征值計(jì)算管樁夕卜徑 d=500mm=0.50m 內(nèi)徑 d1=500-2X 125=250mm=0.25m, hb=0.20hb/d=0.20/0.50=0.40,入 p =0.16X0.4 0=0.06(1)單樁豎向極限承載力標(biāo)準(zhǔn)值計(jì)算A=it (d 2-d 12)/4= 3.14 X(0.50 2-0.25 2)/4=0.15m 2,Api =兀 d12/4= 3.14 X 0.25 2/4=0.

6、05m 2QSk=uEq-ki =Tt d匯 qsiki =3.14 X 0.50 X 8.00=12.56 kNQk=qpk(Aj + 入 pApi )=9000.00 X (0.15+0.06 X 0.05)=1377.00 kN, Qk= Qsk+ Qk=12.56+1377.00=1389.56kNR=1/KQk=1/2 X 1389.56=694.78 kN(2)樁基豎向承載力計(jì)算1)軸心豎向力作用下Z=446.88kN v R=694.78kN,豎向承載力滿足要求。2)偏心豎向力作用下Zmax=782.22kN < R=1.2 X 694.78=833.74kN,豎向承載力滿

7、足要求。4 .樁基水平承載力驗(yàn)算(1)單樁水平承載力特征值計(jì)算I=兀(d4-d 14)/64= 3.14 X (0.50 4-0.25 4)/64=0.0029m 4EI=EcI= 2.80 X 107x 0.0 029=81200kN.m2查表得：m=6.00 x 103kN/m4, Xoa=0.010m bo=0.9(1.5d+0.5)=1.13m=1130mma =(mbo/ E cI) 0.2=(6.00 X 1000X 1.13/81200) 0.2=0.61a L=0.61 X 0.20=0.12 <4,按 a L=0.12,查表得：u x=0.053RHa=0.75 X (

8、 a 3EI/ u x) x oa=0.75 X (0.61 3X81200/0.053) X 0.01=2608.14 kN(2)樁基水平承載力計(jì)算Hk=17.50kN v Ra=2608.14kN,水平承載力滿足要求。5 .抗拔樁基承載力驗(yàn)算(1)抗拔極限承載力標(biāo)準(zhǔn)值計(jì)算Tgk=1/nuiN 入 iqsikLi=1/4 X(2.00 X 2+0.50) X 4X 3.20=14.40 kNTuk=S 入 iqsikUiLi =3.20 X 3.14 X 0.50=5.02 kN(2)抗拔承載力計(jì)算Ggp=Ggpi+Ggp2=5.00 X 5.00 X0X 18.80/4 + 5.00 X

9、5.00 X 0.10 X (18.80-10)/4=5.50kNG=Gi + G2=0.15 X0.10 X25+0.15 X0.10 X(2 5-10)=0.60kNTgk/2+Ggp=14.40/2+5.50=12.70kNTuk/2+Gp=5.02/2+0.60=3.11kN由于基樁不承受豎向拉力，故基樁呈整體性和非整體性破壞的抗拔承載力滿足要求。6 .抗傾覆驗(yàn)算ftS覆點(diǎn)基坑深度-5.00傾覆點(diǎn)示意圖a1 =2.00+0.50/2=2.25m,b i =2.00 X 2+0.50/2=4.25 m傾覆力矩 MW =府 Fhh=1800+70.00 X (5.00 -1.50)=204

10、5.00kN m抗傾覆力矩 Mk = (Fk+G) a+2(Tuk/2+Gp)bi=(850.00+937 .50) X 2.25+2X(5.02/2+0.60) X 4.25=4048.31 kN. mM抗/M 傾=4048.31/2045.00=1.98抗傾覆驗(yàn)算1.98 >1.6，滿足要求。7 .樁身承載力驗(yàn)算(1)正截面受壓承載力計(jì)算0 5按照 M作用在對角線進(jìn)行計(jì)算，M=M=2562.30kN . m yi=2.00 X2 =2.83mZ=(Fk +1.2Gk)/n ± My" 2 yi2=(1147.50+1.2 X 937.50)/4 ±(25

11、62.30 X2.83)/(2 X2.832)=568.13 ±452.7 0Zmax=1020.83kN ,Nmin=115.43kNWc=0.85, WcfcA=0.85 X 11.90 X 1000X 0.15=1517.25 kN正截面受壓承載力 =1517.25kN >Zmax=1020.83kN,滿足要求。(2)預(yù)制樁插筋受拉承載力驗(yàn)算插筋采用 HRB335 fy=300.00N/mnf,取 420, As=4X 314=1256mnmfyA=300X1256=376800N=376.80 kNfyA=376.80kN >Nmin=115.43kN,正截面受拉

12、承載力滿足要求。 _ _2M傾/(4x iAs)= 2045.00 X 1000/(4 X 2.00 X 1256)=203.52 N/mmM傾/(4x iA)=203.52N/mm2300.00N/mm2,滿足要求。(3)承臺受沖切承載力驗(yàn)算1)塔身邊沖切承載力計(jì)算F, =F1.2 2 Qk=Fk =1147.50kN , ho=1.50-0.10=1.40m=1400mm3 hp=1.0+(2000-1500)/(2000-800) X (0.9 -1.0)=0.96a 0=2.00-0.50/2-1.70/2=0.90m, 入=a 0/h o=0.90/1.40=0.643 o=0.84

13、/(入 +0.2)=0.84/(0.64+0.2)=1.00Um=4X (1.70+1.40)=12.40m3 hp3 0umftho=0.96 X 1.00 X 12.40 X 1.57 X 1000 X 1.40=26164.99 kN承臺受沖切承載力 =26164.99kN >Ft=1147.50kN,滿足要求。2)角樁向上沖切力承載力計(jì)算N=N =Fk /n+ Mxy" Nyi2=1147.50/4+2562.30 X2.83/(2 X2.83 2)=739.58kN入 1x=入 1y= a 0/h o=0.90/1.40=0.64,c1=C2=0.50+0.25=0.

14、75mV=2N =2X739.58=1479.16 kN3 1x= 3 1y=0.56/(入 1x+0.2)=0.56/(0.64+0.2)=0.673 1x(c2+ a 1y/2)+ 3 1y(c1+ a 1x/2) 3 hpftho=0.67 X (0.75+0.90/2) X 2 X 0.96 X 1.57 X 1000X 1.40=3393.01 kN角樁向上沖切承載力 =3393.0kN >V=1479.16kN,滿足要求。3)承臺受剪切承載力驗(yàn)算Z =Fk /n+ Mxy" Nyi2=1147.50/4+2562.30 X2.83/(2 X2.83 2)=739.5

15、8kNV=2M =2X739.58=1479.16 kN3 hs=(800/h o) 1/4=(800/1400) 0.25=0.87,入=a 0/h o=0.90/1.40=0.64a =1.75/(入 +1)=1.75/(0.64+1)=1.07,b0=5.00m=5000mm3 hsa ftb0ho=0.87 X 1.07 X 1.57 X 1000X 5.00 X 1.40=10230.59 kN承臺受剪切承載力 =10230.59kN >V=1479.16kN,滿足要求。(4)承臺抗彎驗(yàn)算1)承臺彎矩計(jì)算N=Fk /n+ Mxy" 2yi2=1147.50/4+256

16、2.30 X2.83/(2 X2.83 2)=739.58kN,X i=2.00mM=S NX =2X 739.58 X 2.00=2958.32 kN.m2)承臺配筋計(jì)算 2承臺米用 HRB335 fy=300.00N/mmAs=M/0.9f yho=2958.32 X 10 6/(0.9 X 300X 1400)=7826 mrm 2取 2620 197mm 都J筋間距?黃足要求),As=26X 314=8164 mm承臺配筋面積8164mmi> 7826mm，滿足要求。承臺晉矩示意圖8.計(jì)算結(jié)果(1)基礎(chǔ)樁4根。500預(yù)應(yīng)力管樁，樁頂標(biāo)高-2.90m,樁長0.20m；樁混凝土等級 C25,壁厚125mm樁頂插筋420。(2)承臺長(a)=5.00m ,寬(b)=5.00m