广州市轨道交通二十一号线工程路基抗震性测试研究

Seismic Test of the Subgrade of Guangzhou Rail Transit Line 21

摘要:

传统路基动模量法大都进行单路基抗震性能分析，缺乏复合路基抗震性能分析，存在较高的偏差。对广州市轨道交通二十一号线工程路基抗震性进行测试，分析该地地质条件后，通过标准贯入实验法判断原始路基土质液化情况，使用瑞典条分法测试原始路基的抗震性能，判别出该路基液化土层滑动安全系数低、抗震稳定性差，应对其进行复合路基加固。通过圆弧滑动法对加固后的复合路基中碎石桩桩网结构路基以及CFG桩桩网结构路基进行抗震性测试。实验结果表明，所提方法抗干扰性能强且测试结果精度高。

Abstract:

The traditional dynamic modulus method for subgrade analysis provides results with high deviation because it mainly focuses on the seismic performance of a single roadbed and not the seismic performance of composite subgrades. A seismic test method for the subgrade analysis of Guangzhou Rail Transit Line 21 is proposed. After the analysis of geological conditions, the soil liquefaction of the original subgrade is assessed through the standard penetration test. On this basis, the Swedish strip method is used to test the seismic performance of the original subgrade. Results show that the liquefied soil of the subgrade has low safety and poor seismic stability. Thus, the composite roadbed should be reinforced. The seismic performance of the reinforced subgrade is tested through the circular sliding method. Experimental results show that the proposed method has strong antijamming performance and high accuracy.