基于郑州地铁下穿南水北调干渠的Peck公式反演分析

Inversion Analysis of Peck Formula Based on Zhengzhou Subway Running Down the Main Channel of South-to-North Water Transfer

土压平衡盾构隧道下穿通水运行中的南水北调工程,在国内尚属首例。以郑州地铁城郊线土压平衡盾构隧道下穿南水北调中线干渠区间实测数据为依据,将Peck公式法运用于隧道下穿南水北调工程引起的地表沉降预测研究中,利用反演分析法,通过引入最大沉降量修正系数j和沉降槽宽度修正系数k,结合实测数据对Peck公式进行修正,得出适用于郑州地区相似工程的Peck公式,并根据现场实际情况,对不同埋深条件下地表沉降规律进行研究。结果表明:引入最大沉降量修正系数j和沉降槽宽度修正系数k对Peck公式进行改进后,能够获得较准确的地表沉降预测曲线,证明了Peck公式法在隧道下穿南水北调工程引起的地表沉降预测研究中的适用性;在其他条件均相同的情况下,随着隧道埋深的增加,地表最大沉降量逐渐减小,沉降槽宽度逐渐增大。

The South-to-North Water Transfer Project in the earth pressure balance shield tunnel under the water running operation is the first in China.Based on the measured data of the earth pressure balance shield tunnel of the Zhengzhou Metro suburb crossing the middle line of the South-to-North Water Transfer Project,this paper applies the Peck formula method to the prediction of surface subsidence caused by the tunnel going through the South-to-North Water Transfer,introduces maximum settlement correction factor m and combines settlement tank width correction factor k with the measured data to obtain a Peck formula suitable for similar projects in Zhengzhou.Based on the actual situation of the site,the paper studies the law of surface subsidence under different buried depth conditions.The results show that the introduction of the maximum settlement correction coefficient m and the settlement groove width correction coefficient k can improve the Peck formula and obtain a good prediction curve,which proves the usability of the Peck formula method in the study of surface settlement prediction caused by the tunnel going through the South-to-North Water Transfer Project;with other conditions being the same,as the buried depth of the tunnel increases,the maximum surface settlement gradually decreases,and the width of the settlement tank gradually increases.