土与水工结构接触面模型研究

Study on constitutive law of soil-hydraulic structure interface

为了研究土与混凝土接触面的力学性质,对其剪切过程中应力应变曲线的数学模型进行分析。把接触面结构势能分为摩擦势能和粘聚势能两部分,从能量耗散的角度分析接触面剪切破坏机理。从数学特征方程的角度揭示传统双曲线模型的缺陷。根据能量耗散假定,建立接触面应力应变新模型,并给出实验数据的拟合参数。根据库伦准则,推导接触面剪切模量的表达式;根据土与混凝土接触面试验结果统计,建立各参数的确定方法,推荐初步的取值范围。算例模拟说明新模型的正确性。研究成果可供相关的工程设计参考。

To properly understand the mechanical behaviors of soil-concrete interface,an analysis on mathematical modeling of its shear stress-strain curve is conducted.Its shear-resistance energy is divided into friction energy and cohesion energy,and its failure mechanism is analyzed from a angle of energy dissipation.A mathematical equation is used to reveal the weakness of conventional hyperbolic model.A new stress-strain model for the interface is developed by energy dissipation theory,and its fitted parameters are determined with experimental data of various kinds of such interfaces.A formula for tangent modulus of interface is obtained by Mohr-Coulomb criterion and the statistics of experimental data.A method is suggested to determine the parameters,and their empirical values are given.Simulation examples shows improved features of the proposed model.