Stress-strain monitoring technology used in truss overhead crossing installation of pipeline

The installation for truss overhead crossing of large span pipeline is mostly made with pulling (jacking) method, the stress applied on the truss members is complex due to impact of installation load and external factors, and process control plays a critical role in installation. Taking a truss overhead crossing project abroad as an example, the application of stress-stain monitoring technology in selection of bridge route, data acquisition system, numerical simulation calculation of installation process, selection and installation of sensors, etc.is discussed in detail.The monitoring results show that the maximum stress of a truss is 121 MPa, after field adjustment of pulling speed, the stress of truss is stable within 90 MPa, which is basically consistent with calculated value.The stress-strain monitoring technology is able to provide force condition applied on critical structure locations, with strong feasibility of implementation and can ensure installation safety effectively.