西南交通大学学报2024，Vol.59Issue(6)：1487-1496,10.DOI:10.3969/j.issn.0258-2724.20220642
巨型溶洞区深厚填筑体长期变形特性试验研究
Experimental Study on Long-Term Deformation Characteristics of Deep and Thick Fills in Giant Karst Cave
摘要
Abstract
In order to explore the variation of settlement and stress of the karst cave backfill and natural accumulation layer at different depths,a giant karst cave backfill project in the Yujingshan tunnel of Chengdu—Guiyang railway was studied.A 1∶100 laboratory centrifugal model test was carried out to analyze the long-term deformation law of the inhomogeneous natural soft accumulation layer at the bottom of the karst cave,in which the river sand with a particle size of less than 2 mm was used to simulate the karst cave backfill,and the western Sichuan clay was used to simulate the soft soil layer at the bottom of the karst cave.The reliability of the laboratory test was verified by field monitoring results.The results show that the deformation of the karst cave backfill basically reaches a stable state within 1.5 years after the termination of construction,and the deformation is about 86.9%of the total settlement;the deformation of the soft soil layer is the main component of the soil deformation at the bottom of the tunnel,and its deformation accounts for about 87.5%of the total settlement.The settlement at the bottom of the tunnel is positively correlated with the thickness of the soft soil layer,and when the thickness of the soft soil layer is less than 12.5 cm,it has less influence on the settlement at the bottom of the tunnel.The difference in settlement deformation between the model test and the on-site monitoring is only 3.83%,indicating that the experiments conducted in this article can reflect the long-term deformation characteristics of the soil at the bottom of the tunnel.关键词
深厚填筑体/长期变形/离心模型试验/软土层不均/现场监测Key words
deep and thick fills/long-term deformation/centrifugal model test/inhomogeneous soft layer/on-site monitoring分类
交通工程引用本文复制引用
苏芮,苏谦,贺琛方,董敏琪,王迅,郑余朝..巨型溶洞区深厚填筑体长期变形特性试验研究[J].西南交通大学学报,2024,59(6):1487-1496,10.基金项目
国家自然科学基金项目(51978588) （51978588）
