问题 单项选择题

题11-14 某多层地下建筑采用泥浆护壁成孔的钻孔灌注桩基础,柱下设三桩等边承台,钻孔灌注桩直径为800mm,其混凝土强度等级为C30(f c =14.3N/mm2,γ=25kN/m3)。工程场地的地下水设防水位为-1.0m;有关地基各土层分布情况、土的参数、承台尺寸及桩身配筋等,详见图1-12。

在该工程的试桩中,由单桩竖向静载试验得到3根试验桩竖向极限承载力分别为7680kN、8540kN、8950kN。根据《建筑地基基础设计规范》(GB 50007—2002)的规定,试问,工程设计中所采用的桩竖向承载力特征值Ra(kN),与下列何项数值最为接近

A.(A) 3800

B.(B) 4000

C.(C) 4200

D.(D) 4400

答案

参考答案:A

解析:
根据《建筑地基基础设计规范》(GB 50007—2002)附录Q.0.10第6款:
对桩数三根或三根以下的柱下桩台,取最小值7680kN。
单桩竖向承载力特征值Ra=7680/2kN=3840kN

阅读理解

阅读理解。

     A sense of humor is just one of the many things shared by Alfred and Anthony Melillo, 64-year-old twin

brothers from East Haven who made history in February 2002. On Christmas Eve, 1992, Anthony had a heart

transplant from a 21-year-old donor. Two days before Valentine's Day in 2002, Alfred received a 19-year-ok

heart, marking the first time on record that twin adults each received heart transplants.

     "I'm 15 minutes older than him, but now I'm younger because of my heart and I'm not going to respect

him," Alfred said with a grin, pointing to his brother while talking to a roomful of reporters. who laughed

frequently at their jokes.

     While the twins knew that genetics might have played a role in their condition,they recognized that their

eating habits might have also contributed to their heart problems. "We'd put half a pound of butter on a steak. 

I overdid it on all the food that tasted good, so guess I deserved what I got for not dieting properly."

     The discussion moved to Anthony's recovery. In the five years since his heart transplant, he had been on

an exercise program where he regularly rode a bicycle for five miles, swam each day, and walked a couple

of miles. He was still on medication, but not nearly as much as Alfred, who was just in the early stage of his

recovery.

     "Right now I feel pretty young and I'm doing very well," Anthony said. "I feel like a new person."

     Alfred said his goal, of course, was to feel even better than his brother. But, he added, "I love my brother

very much. We're very close and I'm sure we'll do just fine."

1. This article is mainly about _____.

A. the danger of heart transplant surgery

B. becoming young by getting a new heart

C. the effect of' genetics on the heart

D. the twin brothers who received heart transplants

2. What did Alfred and Anthony have in common?

A. Lifespan. 

B. Career goals.

C. A sense of humor.

D. Love for bicycling.

3. What did Alfred and Anthony think caused their heart problems?

A. Exercise.

B. Diet.

C. Surgery.

D. Medicines.

4. Why did Alfred say, "I'm 15 minutes older than him, but now I'm younger because of my heart"? 

A. His heart transplant surgery was more successful than Anthony's.

B. His recovery from the heart surgery was faster than Anthony's.

C. His exercise program was better than Anthony's.

D. His new heart was younger than Anthony's.

问答题