问题 问答题

试述影响水泥混凝土强度的主要原因及提高强度的主要措施。

答案

参考答案:影响硬化后水泥混凝土强度的因素包括:水泥的强度和水灰比;集料特性;浆集比:湿度、温度及龄期;试件形状与尺寸、试件温度及加载方式等试验条件。
提高混凝土强度的措施主要包括:选用高强度等级水泥和早强型水泥;采用低水灰比和浆集比;掺加混凝土外加剂和掺合料;采用湿热处理(如蒸汽养护和蒸压养护);采用机械搅拌和振捣等。

阅读理解

阅读理解。

     NewYork Tuesday April 12-Dustin Hoffman fan Pamela Crack got the shock of her life when the

movie star telephoned her as she was doing her housework.. Crack, 58, said she was "flabbergasted"

when she picked up the phone and heard the star at the other end.

     "It's not every day you get a Hollywood superstar phoning you when you're doing the housework,"

Crack told The Sun, "It was a moment I'll never forget."

     Hoffman was in the back of a London taxi driven by Crack's husband, Dave, when he made the call

after being told Pamela was a fan. Dave Crack later became the star of Hoffman's speech at the Bafta

award ceremony Sunday, where the 62-year-old American actor presented the Best Film award.

     "He said to give him a mention," Hoffman told the audience to a burst of laughter. "Cheers Dave."

Taxi driver Crack said the Hollywood star was a joy to drive from the moment he got into the taxi eating

a cheese and tomato sandwich.

      "I said 'You're that Dustin Hoffman, aren't you?' and he said, 'Yes I am-would you like a sandwich?'

I was a bit surprised but I took a sandwich from him and ate it hungrily."

1. How did Dustin Hoffman learn that Pamela was a fan?

A. He learned it at a dinner party.

B. He learned it from Dave Crack.

C. He learned it when he was at the Bafta ceremony.

D. He learned it when he was watching a Hollywood movie.

2. What does the underlined word "flabbergasted" in the first paragraph probably mean?

A. pleased.

B. honored.

C. frightened.

D. surprised.

3. What was Hoffman doing when he talked about Dave Crack?

A. He was riding in a taxi.

B. He was presenting the Best Film award.

C. He was talking to Pamela on the phone.

D. He was eating a cheese and tomato sandwich.

4.Which of the following is the correct order of events mentioned in the article?

a. Hoffman mentioned Dave's name in his speech at the ceremony.

b. He got into Dave Crack's taxi in London.

c. He telephoned Pamela Crack.

d. He talked to Dave Crack.

A. bdca

B. bdac

C. cbda

D. cdba

单项选择题