西弥浦泵闸工程混凝土劣化力学试验研究

Experimental Study on Concrete Deterioration Mechanics of Ximipu Pump Sluice Project

为研究西弥浦泵闸工程混凝土在干湿作用下的力学劣化特征,设计并开展了常规干湿与物化侵蚀干湿的室内力学试验。试验得出:(1)干湿作用对混凝土劣化效应高于常规水浸泡;常规水浸泡时间因素不会影响混凝土应变破坏特征;增大围压,混凝土受水浸泡劣化效应会减弱。(2)化学溶液浸泡下,时间愈长,试样应力受削弱愈显著,且劣化效应超过干湿物理作用;当改变化学溶液浓度,试样应力应变形态特征保持一致,浸泡浓度对混凝土承载能力影响在130 g/L更显著;在较小浓度的化学溶液中,混凝土具有一定抗侵蚀能力。研究结果揭示了水工混凝土力学劣化机理。

In order to study the changes in mechanical degradation characteristics of concrete in the Ximipu pump gate project under different environmental dry and wet conditions,indoor testing methods were used to design and carry out mechanical tests under conventional dry and wet conditions and physical and chemical erosion dry and wet conditions.The test results show that the mechanical deterioration effect of dry wet physical action on concrete is higher than that of conventional water immersion.The conventional water immersion time factor does not affect the strain failure characteristics of concrete,and remains consistent under the same confining pressure.Increasing the confining pressure will weaken the deterioration effect of concrete soaked in water.When immersed in a chemical solution for more than 24 hours,the sample exhibits strong plastic strain characteristics,while after reaching a peak below 24 hours,it exhibits strain softening characteristics.Under the immersion of chemical solution,the longer the time,the more significantly the stress of the sample is weakened,and it exceeds the physical effects of dry and wet on the concrete.When the concentration of the chemical solution is changed,the stress-strain morphology characteristics of the sample are consistent.The soaking concentration has a more significant impact on the bearing capacity of concrete at 130g/L.Under a certain chemical solution concentration,concrete has corrosion resistance.The paper is helpful to the experimental study on mechanical deterioration of hydraulic concrete.