某钢筋混凝土T形截面简支梁，计算跨度6m，T形截面尺寸为：b=250mm，h=650mm，
。采用C30混凝土，纵筋为HRB400级，配置纵筋
。荷载效应的标准组合值Mk=550kN·m，准永久组合值Mq=450kN·m。最外层纵筋的混凝土保护层厚度30mm，活荷载的准永久值系数为0.5，结构安全等级二级。取as=70mm。
试问，纵向受拉钢筋应变不均匀系数ψ，与下列何项数值最为接近（）。
A．0.980
B．0.970
C．1.000
D．1.003
参考答案：A
解析：
解答如下：
根据《混凝土结构设计规范》7.1.2条：
Scientists say they have found key clues（线索）into how long we will live. One of them is a firm __21___. British researchers believe a firm strong handshake is not just a __22___ of confidence but also an indicator of a long life. Lead author Dr Rachel Cooper of University College London said her study looked __23___ 33 different reports on the __24___ of handshakes. The research involved more than 50,000 men and women and __25___ 40 years. Dr Cooper concluded that __26___ with weaker handshakes were 70 per cent more likely to die earlier than those with the __27___ handshakes. She concludes that people with a firm strong handshake __28___ from a happy childhood that __29___ a healthy diet and __30___ of exercise. The new study, __31___ in the British Medical Journal, also found other signs of living a longer life. These 'measures of __32___ capability' include walking at a faster pace, getting out of a chair quickly, and being able to __33___ on one leg. The study showed that slow walkers were almost three times __34___ to die at a younger age than those who walked quickly and actively. Those who __35___ to get up from their armchairs were twice as likely to die earlier than those who sprang __36___ their chairs. Dr Cooper believes there __37___ more research into the link __38___ physical capability and a long life. “Research that helps people to __39___ a long and healthy life is ever more important to help provide for an ageing __40___.” she said.
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