双向板按弹性方法计算实例

1、双向板按弹性方法计算实例楼盖平面布置双向板肋形楼盖梁板结构布置如图，钢筋混凝土板厚h150mm楼面面层为20mm厚水泥砂浆抹面(丫=20kN/m3)，板底为15mm厚石灰砂浆粉刷(Y17kN/m3)活载标准值q=5.4kN/m2混凝土为C35级板中受力筋及分布k筋采用级钢筋；梁中受力筋采用级钢筋；梁中箍筋和架立筋采用级钢筋。柱距为，板的弯矩折减系数为：为；均为图，楼盖平面布置板的荷载计算恒载20mm厚水泥砂浆抹面20,0.02二0.4Nm2/150mm钢筋混凝土板20,0.153.75KNm215mm石灰砂浆17,0.0150.26Nm/2标准值g0.4+3.75+0.26=4.41kKNm2

2、/活载标准值q5.4KNm2/k可变荷载效应起控制作用，=1.2=1.3GQTOC o 1-5 h z设计值g二1.2,4.41二5.292m2,设计值q二1.3,5.4二7.02m2荷载设计值p二g+q=5.292+7.02二12.312m2p二g+q/2二5.292+7.02/2二8.80m2p=q/2=7.02/2=3.51m2板的内力计算及配筋中间区格板B1l/1=1.0y计算跨度：l=6.9ml=6.9mxy单位板宽弯矩（KNm/m）跨中弯矩：荷载按棋盘布钢，系数（6pl2系数（1pl2x6pl2x0.0205,8.80+0.0429，3.51x系数（6pl2系数（x支座弯矩：荷载按

3、满布a支座Ma系数（）xb支座Mb系数（）y配筋计算：spl2xpl2x0.0205,8.80+0.0429,3.510.0513,12.312,6.92=30.070.0513,12.312,6.92=30.07,9=130mm,h=120mm。跨中正弯矩配筋选用0 x0y15.7615.76=270N/mm2yAs,minp=0.45f/f=0.45,1.57/270=0.262%minty=pbh=0.00262,1000,150=393mm2min跨中截面：Asx0.8M0.8,15.76,1064=378mm2Afh270,0.95,130s,minys0 x0.8M0.8,15.7

4、6,1064=410mm2fh270,0.95,120ys0y实配钢筋帕/10150,429mm2（方向相同）Asya支座.0.8,Ma0.8,30.07,106Aa=x=721mm2sxfh270,0.95,130ys0 x实配钢筋12150,754mm23.2边区格板B2计算跨度：l二6.9m,l二6.90.120.15+0.3二6.93m,l/1二1xyxy单位板宽弯矩(KNm/m)跨中弯矩：荷载按棋盘布(KNm/m)M系数（5pl2系数（）pl2（0.0261X8.80+0.0429x3.51）x6.92二18.11xxxM系数（5p12系数（5pl2（0.0219x8.80+0.04

5、29x3.51）x6.92二16.34yxx支座弯矩：荷载按满布b支座Mb系数（）pl20.05x12.312x69=29.31yxc支座Mc系数（）pl20.06x12.312x69=35.17xxd支座Md系数（）pl20.06x12.312x69=，35.17xx配筋计算：M18.11x106跨中截面A=x=543mm2sxfYh270 x0.95x130ys0 xM16.34x106A=y=531mm2syfyh270 x0.95x120ys0y实配钢筋10/12150,639mm2（方向相同）支座截面b支座支座弯矩取板B与板B计算中的较大值KN7m/m21Absy30.07x106=

6、977mm2270 x0.95x120实配钢筋1075,1047mm2c支座Acsx35.17x106270 x0.95x130=1055mm2实配钢筋10/1275,1277mm2d支座配筋计算见B33.3角区格板B3计算跨度：l=6.90.120.15+0.3=6.93mm,l=6.93mm,l/1=1.0 xyxy单位板宽弯矩（KNm/m5跨中弯矩：荷载按棋盘布（KNm/m5M系数（4pl2系数（）pl2（0.0281X8.8,0.0429x3.51）x6.932二19.11xxxM系数（4pl2系数（4pl2（0.0289x8.8,0.0429x3.51）x6.932二19.45yxx支座弯矩：荷载按满布d支座Md系数（4pl20.0677x12.312x6.932=40.03xx配筋计算：M19.11x106跨中截面A=x=573mm2sxfh270 x0.95x130ys0 xA=My=19.45x106=632mm2syfh270 x0.9