Hysteretic Characteristic Curve Monitoring and Finite Element Analysis in Nondestructive Testing of Fabricated Foundation Pit

In this paper, Strain gauge monitoring and strain gauge monitoring were compared, the underground structure health monitoring system was adopted. Based on the monitoring instrument, lateral displacement and deformation of the underground prefabricated structure was mainly measured. Through the analysis on the monitoring data, the deformation was small, which is in good agreement with that of the finite element analysis of the underground fabricated structure. The hysteresis characteristic curve of the steel panel-polymer composite structure with different thickness and scale was obtained. The experimental results show that the hysteresis characteristics of the composite structure attenuated with the length-to-thickness, whilst the load-bearing capacity of the steel panel-polymer structure increased. The increase in the thickness of the polymer layer enhanced the flexibility of the composite structure and with larger length-to-height ratios, the composite structure exhibited larger cross-section area for bearing the load. Through the analysis of the underground assembled structure monitoring data, it is concluded that the thicknesses of the steel panel and the polymer layer were more suitable to be designed at about 6 and 20 mm respectively. The economics of materials were considered, and it will also provide a theoretical basis for the development and utilization of underground prefabricated structures.