混凝土局部承压强度较其非局部承压时的强度为高,其主要原因是由于混凝土在局部承压下,周围混凝土起着横向约束作用。构件截面A_d与局部承压面A_c比值越大,周围混凝土对局部承压区的约束作用也越大,从而局部承压强度提高也越大。在我国钢筋混凝土结构设计规范(TJ10-74)中就根据混凝土套箍强化理论,规定了构件的局部承压强度提高系数以计 The local concrete compressive strength of concrete is higher than its non-local compressive strength. The main reason is that the surrounding concrete plays a lateral restraint role due to the concrete under partial pressure. The greater the ratio of the member section A_d and the partial pressure bearing surface A_c, the greater the confining effect of the surrounding concrete on the partial pressure zone, and the greater the local bearing strength. In China’s reinforced concrete structural design specification (TJ10-74), according to the reinforcement theory of concrete cuffs, the local compressive strength improvement coefficient of components is specified as