1、一根简支搁置的钢筋混凝土梁宽50cm,高100cm,跨距6m,单位长度重量12.4KN/m,试判别下列各题:
①自重情况下,梁的路中弯矩两支座处剪力分别为;·dzÒóJØbbs.3c3t.comã¨x«|ø1
②在梁的跨中施加50KN集中荷载,则梁跨中弯矩和支座剪力分别为;·dzÒóJØbbs.3c3t.comã¨x«|ø1
③在梁的二个三分点处(即距2个支座各2米处)各施加30KN荷载,则梁跨中弯矩和支座剪力分别为。·dzÒóJØbbs.3c3t.comã¨x«|ø1
2、某工程对一根长40m的预应力混凝土空心桩进行静载桩试验,要求进行到地基土破坏,桩身截面尺寸为500mm×500mm。空心直径200mm,桩顶和桩端各有2m空心段,预计沉桩最大试验荷载36000KN。·dzÒóJØbbs.3c3t.comã¨x«|ø1
①试桩与锚桩之间中心距不得小于()·dzÒóJØbbs.3c3t.comã¨x«|ø1
②试验采用快速维持荷载法,每级加载和卸载时间分别为()·dzÒóJØbbs.3c3t.comã¨x«|ø1
③各级荷载及桩顶对应沉降见下表·dzÒóJØbbs.3c3t.comã¨x«|ø1
荷载KN·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 600·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 900·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 1200·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 1500·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 1800·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 2100·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 2400·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 2700·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 300·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 3300·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 3600·dzÒóJØbbs.3c3t.comã¨x«|ø1
|
沉降mm·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 2.1·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 3.8·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 5.7·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 8.0·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 10.5·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 13.2·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 16.3·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 19.6·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 23.4·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 44.5·dzÒóJØbbs.3c3t.comã¨x«|ø1
| 76.8·dzÒóJØbbs.3c3t.comã¨x«|ø1
|
·dzÒóJØbbs.3c3t.comã¨x«|ø1
沉桩极限承载力()·dzÒóJØbbs.3c3t.comã¨x«|ø1
④试验时采用10根对称布置的锚桩,锚桩尺寸与试桩相同,锚桩主筋采用Φ25钢筋,抗拉强度设计值为310KPa,则每根锚桩至少配置()根Φ25钢筋,写出计算过程。·dzÒóJØbbs.3c3t.comã¨x«|ø1
⑥桩的极限端阻力(),写出计算过程。·dzÒóJØbbs.3c3t.comã¨x«|ø1
5、某梁跨中载面处测点布置如下图所示,已知ε1=-90με,ε2=-80με,ε3=10με,ε4=100με,ε5=110με,E=30GPa,截面宽b=100mm,截面高h=200mm,求该截面上的轴力N和弯矩My·dzÒóJØbbs.3c3t.comã¨x«|ø1
·dzÒóJØbbs.3c3t.comã¨x«|ø1
·dzÒóJØbbs.3c3t.comã¨x«|ø1
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