宁波轨道交通4号线盾构隧道联络通道多种工法实践研究

Construction Methods for Connecting Passages in Shield Tunnel of Ningbo Rail Transit Line 4

机械法联络通道施工工法包含盾构法和顶管法2大类。为分析机械法和既有冻结法工艺的异同点,以宁波轨道交通4号线盾构隧道21座联络通道为背景,分析其结构特征、结构安全性、环境影响、施工工效、能源消耗等。分析结果表明:1)通过将不同工法的主隧道结构保持一致,保证了主隧道结构的标准化;2)不同工法施工均能满足功能、结构安全和周围环境保护的要求;3)机械法相对于冻结法施工引起的主隧道收敛变形更小,更有利于结构安全;4)在同等条件下,机械法施工时间约为冻结法的1/2,同时冻结法每延米联络通道耗电量约为机械法的10倍。

The mechanized construction method for connecting passages can be divided into shield and pipe jacking methods.To clarify the difference between mechanical and freezing methods,the structural characteristics and safety,environmental influence,construction efficiency,and energy consumption of the 21 connecting passages of shield tunnel of Ningbo rail transit line 4 are analyzed.Analytical results demonstrate the following.(1)The main tunnel structures constructed using different construction methods are uniform to guarantee the standardization of the main tunnel structures.(2)Various construction methods can meet relevant structural functions,structural safety,and environmental requirements.(3)The convergence deformation of the main tunnel obtained using the mechanical method is smaller than that obtained using the freezing method,which promotes structural safety.(4)Under the same conditions,the mechanical method requires approximately half the time of the freezing method.Moreover,the power consumption per linear meter of connecting passages obtained using the mechanical method is one-tenth of that obtained using the freezing method.