盾构法双管隧道施工引起的地表沉降预测及特征分析

盾构法双管隧道施工产生的地表沉降预测方法按照不同的分析原理,可归纳为半经验分析法、理论分析法和数值分析法。分析了各种方法的优缺点,搜集国内外41条双管盾构隧道工程的地表沉降实测曲线,通过对曲线分布形态及其成因的分析以及地表最大沉降值数据的归纳整理,总结了双管隧道施工地表沉降分布的3大特点,即:1)地表沉降曲线主要呈现"单峰"和"双峰"2种形态,双管隧道间距及埋深是决定曲线形态的重要因素;2)影响地表沉降曲线形态的因素主要为地质和环境因素以及施工因素;3)地表最大沉降值与隧道埋深、双管隧道的间距、地层条件以及采用的盾构方法等均有密切的联系。

Prediction and Characteristic Analysis of Ground Surface Settlement Caused by Construction of Twin-tube Tunnels

Based on the different analysis principles, the methods used to predict the ground surface settlement caused by the construction of twin tube tunnels are classified into semi empirical analysis method, theoretical analysis method and numerical analysis method, whose advantages and disadvantages are analyzed. Curves of measured ground surface settlement caused by the construction of 41 twin tube tunnels at home and abroad are collected. Through the analysis on the shape and causes of the curves as well as the analysis on the data of the maximum ground surface settlement, the following three main characteristics are summarized for the distribution curves of the ground surface settlement caused by the shield construction of twin tube tunnels: 1) The ground surface settlement curves mainly present “unimodal” and “bimodal” forms. Both the distance between twin tubes and the tunnel depth have great influence on the curve forms; 2) The main factors that have influence on the ground surface settlement distribution curves include the geological factors, the environmental factors and the construction factors; 3) The maximum ground surface settlement is closely related to the tunnel depth, the distance between the twin tubes, the ground conditions and the shield tunneling method.