问题 问答题

已知地基土中某点的最大主应力σ1=600kPa,最小主应力σ3=200kPa,试求最大剪应力τmax及其作用方向,与大主应面成夹角α=15°的斜面上的正应力和剪应力。

答案

参考答案:

σ1=600kPa,σ3=200kPa,绘制莫尔应力圆(见下图)。

当2α=90°时τ=τmax=200kPa

当α=15°时

阅读理解

The Winter Olympics is also called the White Olympics.At this time,many colorful stamps are published to mark the great Games.The first stamps marking the opening came out on January 25th,1932 in the United States for the 3rd White Olympics. From then on,publishing stamps during the White Olympics became a rule.

During the 4th Winter Olympic Games a group of stamps were published in Germany in November l936. The five Olympics rings were drawn on the front of the sportswear.It was the first time that the rings appeared on the stamps of the White Olympics.

In the 1950s,the stamps of this kind became more colorful.When the White Olympics came,the host countries(主办国) as well as the non-host countries published stamps to mark those Games.China also published four stamps in February 1980 when the Chinese sportsmen began to take part in the White Olympics.

Japan is the only Asian country that has ever held the White Olympics.Altogether 14,500 million stamps were sold to raise money for this sports meeting.

Different kinds of sports were drawn on these small stamps.People can enjoy the beauty of the wonderful movements of some sportsmen.

小题1:The White Olympics and the Winter Olympics_________.

A.are the same thing

B.are different games

C.are not held in winter

D.are held in summer小题2:The world made it a rule to publish stamps to mark the great world games_______.

A.after the year 1936

B.after the 3rd White Olympics

C.before the 3rd White Olympics

D.before the year 1932小题3:Which of the following is TRUE?

A.Only the host countries can publish stamps to mark those Games.

B.Only the non-host countries can publish stamps to mark those Games.

C.All the countries can publish stamps to mark those Games.

D.Japan can’t publish stamps to mark those Games小题4:What may appear on the stamps of the White Olympics?

A.Basketball.

B.Table tennis.

C.Football.

D.Skating.

选择题