盾构施工引起环境振动的实用计算方法

A method to predict vibration responses induced by metro shield tunneling

在中心城区进行盾构施工引起的振动对环境的影响问题日渐突出,需要对盾构施工过程中可能产生的环境振动影响进行可靠地预测分析。本文以北京地铁8号线盾构施工为研究背景,针对典型工况,首先基于盾构作业面现场测试数据,利用灰关联熵方法和多元回归方法进行因素分析,提出了振动振源的主控因素(地层条件)及其量化特征参数(掌子面地层加权动弹性模量),影响振动的主要施工参数(刀盘扭矩、盾构总推力)。在此基础上,基于典型断面的环境振动响应现场测试,考虑振动在周围地层传播过程中的距离衰减与阻尼衰减,提出了盾构施工引起环境振动实用计算方法,并利用现场实测数据进行了方法的有效性验证。为盾构施工引起环境振动的预测、评估以及施工过程控制提供了有效的方法支撑,填补了国内外研究空白。

Environmental vibration responses induced by metro shield tunneling need to be predicted for evaluating these vibration impacts on the surrounding area. Metro shield tunneling for Beijing subway line NO.8 was studied. Analyses(the grey relation entropy method and the multiple regression analysis method) on field monitoring at the working face of the shield construction site suggests that the main factors controlling the shield construction vibration source are the stratum condition and its quantization characteristic parameter(the weighted dynamic elastic modulus of tunnel face stratum), and the cutter head torque and the gross propulsion. Furthermore, by studying field tests of the environmental vibration responses induced by metro shield construction, considering the distance attenuation regularities and the damping attenuation characteristics of the vibration propagation process in the surrounding stratum, a practical calculation method to predict the environmental vibration responses is found, and was approved by comparing predicted data against corresponding field recorded ones.