某带壁柱墙，截面尺寸如图所示，采用烧结普通砖MU10，M5水泥混合砂浆砌筑，砌体施工质量控制等级为B级。墙上支承截面尺寸为200mm×500mm的钢筋混凝土大梁，梁端埋置长度370mm。已知梁端支承压力设计值为75kN，上部轴向力的设计值为170kN。结构安全等级为二级。
对梁端支承处砌体的局部受压承载力验算，ψN0+N1≤ηγfA1的计算值，左右端项与下列何项数值最为接近（）。
A．80kN＞65kN
B．75kN＞68kN
C．90kN＞65kN
D．70kN＞68kN
参考答案：B
解析：
解答如下：
根据《砌体结构设计规范》5.2.4条：
Al=a0b=182.6×200=36520mm2
A0=370×370+2×155×240=211300mm2
A0/Al=211300/36520=5.79＞3.0，取ψ=0.0
ψN0+Nl=0+75=75kN＞ηγfAl=0.7×1.77×1.5×36520=67.9kN
Diane Ray was completely self-centered and very spoilt. Her parents gave her 36 she wanted, knowing that she would throw a temper tantrum(耍小孩脾气)if they did not. She would scream and kick and 37 on the floor drumming her heels. Her parents always 38 . That was why she was alone on the 39 , wearing an expensive swimsuit. It has taken a massive tantrum to 40 her parents to buy it. They were back at the beach-house, 41 from the tantrum she had thrown when they told her that it was too dangerous to go diving 42 . “Dangerous?” she had said. “You just don’t want me to have 43 . I’m going and if you try to stop me, I’ll scream.” “What are you doing ?” a voice asked. Diane jumped. She did not know that the man was there 44 he spoke . “I’m going diving, ” she answered. “You shouldn’t swim that day, ” the man 45 . “There is a storm coming up.” “You should mind your own 46 !” Diane replied and walked into the gentle waves. “If you go out there you’ll be 47 ,” the man called after her. She did not bother to reply. Diane slipped into the water and dived 48 until white caps began rolling in and it became harder to 49 against the current (水流). Saltwater hit against her face, making it 50 to breathe. Oh, why had she not listened to advice. Panicking, she began to 51 . Then, just as it seemed as if she would slip beneath the surface, she heard a 52 voice. “Hold on ! I’m coming.” With 53 , she saw the old man rowing an ancient-looking boat towards her. “I hope you’ve learned a lesson. You put us both in 54 , ” he shouted angrily, as he dragged her over the side of the 55 . Gratefully, Diane thanked him and ran towards the beach-house.
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