问题 单项选择题

某框架结构办公楼边柱的截面尺寸为800mm×800mm,采用泥浆护壁钻孔灌注桩两桩承台独立基础。荷载效应标准组合时,作用于基础承台顶面的竖向力Fk=5800kN,水平力Hk=200kN,力矩Mk=350kN·m,基础及其以上土的加权平均重度取20kN/m3,承台及柱的混凝土强度等级均为C35。抗震设防烈度7度,设计基本地震加速度值0.10g,设计地震分组第一组。钻孔灌注桩直径800mm,承台厚度1600mm,h0取1500mm。基础剖面及土层条件见图1-14。
提示:1.本题按《建筑桩基技术规范》(JGJ 94—2008)作答。
2.C35混凝土,ft=1.57N/mm2


试问,地表下5.5m深处液化判别标准贯入锤击数临界值Ncr,与下列何项数值最为接近
提示:按《建筑抗震设计规范》(GB 50011—2010)作答。

答案

参考答案:B

解析: 根据《抗规》4.3.4条,[*]
对于粉砂ρc=3 β=0.8
查表4.3.4 N0=7 ds=5.5 dw=3.5
Ncr=7×0.8[ln(0.6×5.5+1.5)-0.1×3.5]=6.8 取7

阅读理解

When the earthquake hit Japan on March 11,workers in a supermarket in Japan didn’t run away when they felt the shaking. Instead, they held on to the shelves and tried to stop the goods(货物)from falling down.

Reporters from NHK, the country’s largest TV station, stayed calm in front of cameras during the earthquake, even though some were facing real danger.

The earthquake was the most powerful one to hit Japan in the country’s history. But Japan’s reaction(反应) to the accident has shown that it is the most earthquake-prepared country in the world. The calm the Japanese showed during and after the quake has impressed the world.

This is because Japan has “an earthquake culture”.Japanese people are taught how to prepare for and react to earthquakes from a young age.

Schools in Japan organize earthquake practices every month. They make students become familiar with being in an earthquake.

Japan also has a good earthquake warning system(警报系统).Warnings were broadcast on television, radio and mobile phones nine seconds after experts(专家)first knew about the quake on March 11.

The warning system is unable to predict earthquakes. But it can usually alert people about 15 seconds before they feel the effects. Even 15 or 20 seconds can be enough time to save people’s lives.

小题1:How did Japanese people react when the big earthquake hit Japan on March 11?

A.They felt angry.

B.They were scared.

C.They stayed calm.

D.They were frustrated.小题2:Which of the following is TRUE according to the passage?

A.Japan’s reaction to the earthquake impressed the world.

B.Japanese schools organize earthquake practice every day.

C.Japan has a warning system that can predict earthquakes.

D.Japanese people learn about earthquake safety only from universities.小题3:.After experts first knew about the quake on March 11,warnings were not broadcast ____.

A.on radio

B.on the movie

C.on television

D.on mobile phones小题4:What does the underlined word “alert”mean in Chinese?

A.改善

B.提高

C.提醒

D.改变小题5:What does the story mainly tell us about?

A.Japan’s earthquake culture.

B.The bad results caused by the earthquake.

C.Japanese people were scared after the earthquake.

D.Japanese people were homeless after the earthquake.

单项选择题