海水喷淋干湿循环持载RC受弯梁试验研究

为了解决沿海地区正常使用工作状态下承受较大持续荷载钢筋混凝土(reinforced concrete,RC)梁的力学性能劣化问题,通过实验室模拟经历180 d大气环境+180 d海水喷淋干湿循环(简称Ⅰ腐蚀)或180 d海水喷淋干湿循环+180 d大气环境(简称Ⅱ腐蚀)后,由静力加载试验测试RC梁试件力学性能劣化规律.试验结果,RC梁试件在不同持续荷载和一定腐蚀环境共同作用下,随着持续荷载增大其屈服荷载P_y、极限荷载P_m和延性系数u降幅变大.Ⅱ腐蚀梁试件的P_y、P_m和u降幅大于Ⅰ腐蚀梁试件的P_y、P_m和u降幅.梁试件的抗弯刚度随着持续荷载增大而降低.试验结果表明较大持续荷载与一定腐蚀环境共同作用对RC梁力学性能劣化影响明显.

Experimental Study of RC Flexural Beams Under Sustained Damage Load and Seawater Spraying Dry-Wet Cycles

In order to solve the problem of deterioration of mechanical properties of reinforced concrete (RC) beam in coastal zoneunder normal working condition of the larger load, the mechanical behavior deterioration of RC beam specimens was investigated by static loading test, after they experienced 180 d atmospheric environment and 180 d seawater spraying dry-wet cycle(Simplified byⅠcorrosion);or they experienced 180 d seawater spraying dry-wet cycles and180d atmospheric environment (Simplified by Ⅱcorrosion) by the laboratory simulation. Test results yielded load Py,limited load Pm,and ductility factor u of them decreased when the beam specimens were acted on by sustained damage load in Ⅰ corrosion (or Ⅱ corrosion); and PyPmand u decreased more with the sustained damage load increasing; the decrease of PyPmand u for the beam specimens inⅡcorrosion were greater than those of PyPmand u for the beam specimens inⅠcorrosion. The flexural stiffness of the beam specimens became smaller with the increase of the sustained damage load. The experimental results show that the effect on the mechanical properties of RC beams is obvious form the larger sustained damage load and certain corrosive environment.