Abstract:
In order to study the spatial distribution and variation pattern of the external load of deep-buried over? sized-section steel pipes in pipe jacking construction, the effect of grouting load and the structural stress characteristics, etc., taking the tunnel project of Jing'an Temple Station of Shanghai Rail Line 14, which is constructed by pipe jacking method, as the research context, this paper carries out field monitoring and tests by using water and soil pressure gauges and strain gauges, and followed by collection, processing and analysis of the external load and structural strain data. The research results show that under the steady load condition, the circumferential distribution of the external load of the pipe segment is generally in pear-shape, while the measured values of the total soil and water pressure at the top of the pipe segment is basically consistent with the theoretical values; grouting loads during construction can be counted as 1 time the total stable pressure at the top; the latticed steel pipe segment still conform to the plane section assumption; the internal force transfer between the pipe segments has a large impact on the circumferential stress and strain, and the longitudinal force at the pipe segment ring joint affects the stiffness of the ring joint, which in turn affects the internal force transfer coefficient; the incidental ground load causes a great increment in the external load of the structure but a small increment in the strain of the structure.
PAN Weiqiang1 JIAO Bochang2 LIU Xian2 ZENG Hua3 JI Maojie3
.Field Test Research on the Contact Pressure and Stress Characteristics of Jacked Steel Pipes with Deep-buried Depth and Large-section[J] MODERN TUNNELLING TECHNOLOGY, 2021,V58(5): 104-113