不同温度条件下冻结道砟力学特性研究

Study on mechanical properties of frozen ballast under different temperature conditions

无侧限抗压试验是研究道砟力学特性的重要手段。为探究冻结道砟在不同温度下细观力学特性以及准确的细观参数,利用离散元软件进行无侧限抗压模拟,采用平行黏结模型模拟冰对颗粒的胶结作用。结果表明:离散元与实验的抗压强度—位移曲线较为吻合。冻结道砟的抗压强度随温度降低而升高,细观方面冻结道砟的平行黏结刚度、黏结强度也呈现相同的规律,为后续相似材料抗压试验研究提供可靠的数值分析方法。

Unconfined compression test is an important means to study the mechanical properties of ballast.In order to explore the meso-mechanical properties and accurate meso-parameters of frozen ballast at different temperatures,the discrete element software was used for unconfined compression simulation,and the parallel bonding model was used to simulate the cementation effect of ice on particles.The results show that the discrete element is in good agreement with the compressive strength-displacement curve.The compressive strength of frozen ballast increases with the decrease of temperature,and the parallel bonding stiffness and bonding strength of frozen balast also show the same law in meso-view.It provides a reliable numerical analysis method for the subsequent compressive test of similar materials.