土工袋减振与耗能的数值模拟

土工袋减振效果良好且造价低、施工简单，现研究与应用多基于现场重复试验，而少见有减振机制研究。根据土工袋的消能减振作用原理，利用离散单元法，建立土工袋减振过程中能量耗散方程；模拟单一竖向加载条件下各部分的能量耗散，从能量守恒角度对计算结果进行合理性分析，验证所建立的能量耗散方程与计算方法的正确性；然后利用经验计算模型，对土工袋单体进行1 000 N/s加载速率条件下3次循环加载时各部分能量耗散数值模拟，定量研究土工袋单体的减振效果。理论研究表明，土工袋袋子及袋内材料总消耗能量百分比随着加荷与卸荷的进行而呈“波浪状”增减趋势，占总能量的百分比在75%以上，可以起到较好的消能效果。

Numerical simulation of vibration reduction and energy dissipation of soilbags

Soilbags have been understood to be cheap and easy to acquire as well as vibration reduction. However, the research on the effect of soilbag vibration reduction is only based on test results at present; the mechanism of it has rarely been studied. Based on the principle of soilbag energy dissipation, the discrete element method is used to build energy dissipation equation during the process of soilbag vibration reduction. Firstly, using the discrete element method to establish every part of soilbag energy dissipation equations, through numerical simulation of a single soilbag under simple vertical loading condition, from energy conservation perspective to verify that the calculation of each part of the energy is reasonable; meanwhile, the correctness of the established equations of energy dissipation is proved; and then energy dissipation of a single soilbag is simulated from quantitative perspective by using the verified energy dissipation equation under the cyclic loading rate of 1 000 N/s three times. The numerical simulation results show that the percentage of total soilbag and its inside particles energy consumption exhibit obvious wavy shaped fluctuating with loading and unloading; the percentage of it is over 75% of the total energy; this means soilbag can play a good effect on energy dissipation.