?hs?800???h?0????1/4?800????1230??14?0.898
对Ⅰ-Ⅰ斜截面
?1x??0x?0.472(介于0.3~3之间) 剪切系数 ??1.750.472?1?1.188
?hs?ftb0h0?0.898?1.188?1430?6.0?1.23
?11259kN>2Nmax?4617kN (满足要求)
对Ⅱ-Ⅱ斜截面
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?1y??0y?1.203 剪切系数 ??1.751.203?1?0.794
?hs?ftb0h0?0.898?0.794?1430?4.0?1.23
?5016.5kN>2Nmax?4617kN (满足要求)
④承台受弯承载力计算 按公式计算
Mx??NMiyi?2?2308.5?1.8?8310.6kN·m mm2
Asx?x0.9fyh0?8310.6?1060.9?360?1230?20925?20854选用34 28@120,AsMymm2,沿平行y轴方向均匀布置。
??NMixi?2?2308.5?0.90?4155.3kN·m
Asy?y0.9fyh0?4155.3?1060.9?360?1202?10682?10670mm2
选用42 18@140,As⑤局部受压计算
mm2,沿平行x轴方向均匀布置。
承台混凝土强度等级低于柱和桩的混凝土强度等级,应按《混凝土结构设计规范》验算柱下和桩上承台的局部受压承载力,柱的混凝土强度等级C60,承台的混凝土强度等级C30,需要局压验算: 柱局压验算:
Ab??a?b??3b??0.8?2?0.6??3?0.6?3.6m2
Al?ab?0.8?0.6?0.48m2
?l?AbAl?3.60.48?2.74 36
fcc?0.85fc?0.85?14.3?12.155N/mm32
>
Fl?w?lfccAl?1?2.74?12.155?10?0.48?15986KN1.35?8386?11321.1KN
桩局压验算:不需要验算
柱对承台局压验算满足 桩对承台局压验算满足 (6)桩基沉降 柱⑧按有扩散计算
?c?(18.1x1.7?15.1x4.3?18.9x2.9?18.5x3.9?15.5x6.0?17.5?5.1?20?1.1?21?1.8)?464.71
Pok?Pk???Fk?GA/kc??c?7014?19?(5.2?2?25.2?tan8)?(3.2?2?25.2?tan8)?(2.1?25.2)(5.2?2?25.2?tan8)?(3.2?2?25.2?tan8)???? (-18.1x1.7?15.1x4.3?18.9x2.9?18.5x3.9?15.5x6.0?17.5?5.1?20?1.1?21?1.8) ?109.55KPa
?
Z1?0Z2?1.0 zbLb?1(5.2?2?25.2?tan8)2?0.1946???0.2496
?1.1946?S??b??Pok?109.55??4??1.0?0.2496?0??2.9mm?0.002?4800?9.6mm?4Z2??4Z?1??0.4?Esi?15?按不扩散计算
?qsiai2??l??0.1?34?4.3?18?2.9?36?38??3.9?6.0?20?5.1?58?1.1?78?1.8?100??965.6 3??Pok?Pk??c?Fk?Gk?(5.2?3.2)?qsialiA?7014?20?5.2?3.2?2.1-(5.2?3.2)??qsiali5.2?3.2??23.93KPa
Pok=0
?S=0
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