问题 单项选择题

图14-36所示刚架,C截面的转角位移(顺时针为正)为()。

A.Mι/3EI

B.Mι/6EI

C.Mι/2EI

D.-Mι/6EI

答案

参考答案:D

解析:

荷载作用下仅有竖向杆件有弯矩图,虚拟单位力也是只有竖向杆件有弯矩图,利用图乘法求得位移为:-Mι/6EI(逆时针),因此正确答案选择D。

选择题
阅读理解

阅读理解。

     A recent report says about 18% of China teenagers can have problems with their minds. Some students

become worried because they have to study very hard. Others have trouble getting on well with people like

their parents and classmates.

     Zhang Qiang, a Junior 2 student from China, could not understand his teachers in class and was doing

badly in his lessons. He was afraid of exams. When he looked at the exam paper, he couldn't think of anything

to write.   

     Another student, a 15-year-old girl called Wu Yan from Guangdong often argued (争吵) with her

classmates even her parents because of some different ideas. She became so angry with them that she

started  to cut her finger with a knife.

      However, many students who have problems won't go for advice or help. Some think they will look

stupid if they go to see a doctor. Others don't want to talk about their secrets. In order to solve the teenagers'

problems, here is some advice:

     ● Talk to your parents or teachers often.

     ● Take part in group activities and play sports.

     ● Go to see a doctor if you feel unhappy or unwell.

1. Some students became worried because of  _____. 

A. their study

B. their teachers

C. their hobbies

D. their clothes

2. Wu Yan cut her finger with a knife because _____.

A. she was afraid of exams

B. she had no money for a new shirt

C. she could not understand her teachers in class

D. she often argue with her classmates and her parents

3. How many pieces of advice are given to the teenagers who have problems in this passage?

A. Two.

B. Three.

C. Four.

D. Five.