昆明泥炭质土地铁盾构等代层压缩模量试验研究

EXPERIMENTAL STUDY ON COMPRESSIVE MODULUS OF METRO SHIELD GENERATION ZONE IN KUNMING CUMULOSOLS

在城市地铁盾构施工过程中,地表沉降是重要的工程问题之一,不但影响地铁隧道的安全建设,更直接关系到周边紧临建筑物的正常运营。等代层压缩模量是控制地表沉降的关键参数,特别是软弱土层中的地铁盾构。等代层注浆材料与土体的混合比例关系、注浆后的养护时间是直接影响其压缩模量的重要因素。本文依托昆明地铁3号线石咀段泥炭质土层盾构工程,进行注浆材料与泥炭质土的不同比例关系及不同养护时间条件下的压缩模量试验研究。探索泥炭质土层中盾构等代层中浆体与土体的合理比例关系,并提出注浆后何时能达到预期的等代层压缩模量,为泥炭质土地区地铁盾构施工提供参考。

In the construction process of city metro shield,the ground surface subsidence is one of the most important engineering problems, which not only affects the safety of the subway tunnel construction, but also directly relates to the normal operation of the surrounding buildings. The compressive modulus of generation zone is one of the key shield parameters that control the ground surface subsidence, especially to the shield tunneling in soft soil zone. The mixing proportion of the generation zone grouting material and the soil, and the waiting time after grouting are the important factors that affect the compressive modulus. This paper is based on the cumulosol shield tunneling project of Kunming Metro Line 3 Shiju section, with a compressive modulus test of mixtures which havedifferent proportions of grouting materials and cumulosol and different curing times. The reasonable proportion relationship between the shield generation zone paste in the cumulosol zone and the soil are explored. The time to get expected compressive modulus of generation zone after grouting is put forward, which can provide reference for the shield tunneling construction in the cumulosol area.