砂卵石地层盾构施工地表沉降分析及对策

摘要

Settlement is still one of the important problems to be controlled during shield tunnelling. For the characteristics of geologic condition in sand and cobble stratum, the settlement has the features ： hysteresis, concealment, and abruptness. So the problem becomes an urgent problem to be solved. Based on the practice of Chengdu Metro Line 1 and Line 2, the settlements are measured and the data are summarized and analyzed. The settlement laws are found out, which provide the basis to take measures to solve the settlement. The measures can reduce the settlement effectively.%盾构法隧道施工时地表沉降仍然是施工控制中的突出问题之一。砂卵石地层中,由于地质条件的特殊性,地表沉降具有滞后性、隐蔽性、突发性,危害极大,是工程中急待解决的问题。结合成都地铁1号线盾构隧道的工程实践,对地表沉降进行监控量测,并对监控数据进行统计分析,找出变化规律,有针对性地采取相应的治理措施,较好地解决了富水砂卵石地层地表沉降问题。