Research on Risk Assessment Method for Land Subsidence in Tangshan Based on Vulnerability Zoning

The vulnerability zoning of the urban ground subsidence in Tangshan City was investigated in this study, taking into account factors such as the geological lithology, rainfall, population density, road network density, seismic acceleration, and river network density. The main research of this paper is slow land subsidence affecting large territories. A single-factor analysis was conducted using ArcGIS, followed by a grid-weighted overlay analysis. Values were assigned to each factor to generate a vulnerability zoning map. The analytic hierarchy process (AHP) and information value evaluation model were then employed to assess the ground subsidence risk. An evaluation index system was established, comprising the evaluation objective layer, criterion layer, and indicator layer. An evaluation judgment matrix for the ground subsidence risk was constructed, with the calculation of the weight and information value of each risk evaluation indicator, and the total information value of the study area. Four risk levels were determined: high, moderate, relatively low, and low. The findings demonstrate the scientific validity, rationality, and practical applicability of the vulnerability zoning research and risk assessment method for addressing the ground subsidence in Tangshan City. This study contributes to the understanding and management of the ground subsidence risk, providing a robust framework for urban planning and disaster mitigation.