Abstract In this paper, a computation formula is deduced that can be used to judge the safety status of a hazardous buried pipeline when a super-large diameter shield is crossing under it. The relationship between the pipeline′s stress status and the ground deformation above the pipeline is established. Using the measured ground settlement data, the equation for a deflection curve of the buried pipeline is fitted. The stress status of the pipeline is then deduced from the curvature functions, which can be established using a differential calculation for the deflection curve. Finally, the pipeline safety factor is determined by comparing the actual stress to the allowable stress, and this factor can be used as a reference parameter for shield construction. Using an example of large-diameter shield construction from Shanghai, and based on measured data from rings 950 to 1040, the safety factor for pipelines is calculated. The results show that the safety factor varied from 5~15, resulting in a reduction of the pipeline safety. Controlling the shield construction parameters could ensure the pipeline's safety.
Abstract：
In this paper, a computation formula is deduced that can be used to judge the safety status of a hazardous buried pipeline when a super-large diameter shield is crossing under it. The relationship between the pipeline′s stress status and the ground deformation above the pipeline is established. Using the measured ground settlement data, the equation for a deflection curve of the buried pipeline is fitted. The stress status of the pipeline is then deduced from the curvature functions, which can be established using a differential calculation for the deflection curve. Finally, the pipeline safety factor is determined by comparing the actual stress to the allowable stress, and this factor can be used as a reference parameter for shield construction. Using an example of large-diameter shield construction from Shanghai, and based on measured data from rings 950 to 1040, the safety factor for pipelines is calculated. The results show that the safety factor varied from 5~15, resulting in a reduction of the pipeline safety. Controlling the shield construction parameters could ensure the pipeline's safety.
LI Lin
.The Judgment Method and Field Research Regarding Safety for
an Extra-Large Diameter Shield Passing Under High-Risk Pipelines
[J] MODERN TUNNELLING TECHNOLOGY, 2014,V51(5): 134-138
2014, Vol. 51 