复杂应力状态下孔隙水压力对混凝土抗压强度的影响

发布时间：2019-05-16 02:16

【摘要】：将Terzaghi(太沙基)有效应力原理引入到饱和混凝土力学性质的研究中,探讨复杂受力环境下孔隙水压力对混凝土抗压强度的影响机制,建立了符合混凝土材料自身微结构特点的有效应力原理表达式,推导出三向一般应力状态下的孔隙水压力系数公式,用其预测不同围压下混凝土的抗压强度,并在应力空间压子午面内定量描述干燥混凝土及饱和混凝土基体真实应力加载路径的变化,所得到的趋势与试验结果相吻合.研究表明:孔隙水压力的存在改变了混凝土基体真实应力在应力空间的加载过程,从而改变了混凝土材料应力达到峰值时所对应的抗压强度;与干燥混凝土相比,准静态工况下饱和混凝土在各种应力状态下的抗压强度均有所降低,且受初始静水压力、孔隙率及加载路径的影响.从基体真实应力的角度揭示了复杂应力状态下孔隙水压力对饱和混凝土抗压强度的影响机理.
[Abstract]:The effective stress principle of Terzaghi is introduced into the study of mechanical properties of saturated concrete, and the influence mechanism of pore water pressure on compressive strength of concrete under complex stress environment is discussed. The expression of effective stress principle in accordance with the microstructure characteristics of concrete material is established, and the formula of pore water pressure coefficient under three-way general stress state is derived, which can be used to predict the compressive strength of concrete under different confining pressures. The variation of the real stress loading path of dry concrete and saturated concrete matrix is quantitatively described in the meridian plane of stress space pressure, and the obtained trend is in good agreement with the experimental results. The results show that the existence of pore water pressure changes the loading process of the real stress in the stress space of the concrete matrix, thus changing the compressive strength corresponding to the peak stress of the concrete material. Compared with dry concrete, the compressive strength of saturated concrete under quasi-static conditions is lower than that of dry concrete under various stress conditions, and is affected by the initial hydrostatic pressure, porosity and loading path. From the point of view of real stress of matrix, the influence mechanism of pore water pressure on compressive strength of saturated concrete under complex stress is revealed.
【作者单位】：华北水利水电大学水利学院;大连理工大学海岸和近海工程国家重点实验室;黄河勘测规划设计有限公司;
【基金】：国家自然科学基金资助项目(51009020,51209094,51408223,51109081,51309101) 大连理工大学海岸和近海工程国家重点实验室开放基金资助项目(LP1401)
【分类号】：TU528

【共引文献】