Shield underneath pass existing structure construction risk evaluation method

Abstract

The invention discloses a shield underneath pass existing structure construction risk evaluation method, which mainly comprises the following steps of establishing a construction safety risk evaluation index model of a shield underneath pass existing structure based on related literature and engineering experience; acquiring detection data, and performing optimal edge distribution identification on the evaluation indexes based on the monitoring data; constructing a PCBN model based on a Bayesian network, performing risk reasoning, and determining an engineering construction risk level; and onthe basis of the constructed PCBN model, carrying out evaluation index correlation analysis based on a percentage arachnogram and correlation coefficients, and determining key risk factors of the project. According to the method, the Pair-Copula theory and the Bayesian network are combined, inference analysis is carried out on the uncertain risk information, the construction risk state and potential key risk factors of engineering are effectively determined, and more accurate and reasonable construction safety risk comprehensive evaluation of shield underneath passing existing buildings is achieved.

Description

technical field [0001] The invention belongs to the field of construction safety risk assessment of shield tunneling through existing structures, and specifically relates to a hybrid method combining Pair-Copula theory and Bayesian network to solve potential safety problems in the construction process of shield tunneling under existing structures Uncertainty expression and reasoning issues for risk. Background technique [0002] With the rapid development of my country's urban rail transit construction, it is becoming more and more common for shield structures to pass through existing structures. During the construction of structures, the construction environment is complex and changeable, and there are many risk-causing factors and strong correlations during the construction process, which can easily induce deformation and settlement of adjacent existing structures. Real-time dynamic security assessment and decision-making has important engineering significance. [0003] ...

AI Technical Summary

Problems solved by technology

Although these studies have made some contributions to the construction safety control of shield tunneling under existing structures, the theoretical analysis method in the above methods has great limitations in dealing with complex problems, and the solution accuracy is low; the numerical analysis method is based on a large number of assumptions , the workload is large, the accuracy fluctuates greatly, and there is a certain degree of separation from the actual engineering situation; while the model test has the disadvantages of high cost, long time consumption, etc., and cannot accurately describe the engineering geological conditions and related risk factors. influences

At present, from the perspective of risk assessment, there are very few studies on the systematic safety evaluation and early warning of the safety problems of close construction of structures, and the analysis methods are still in the traditional AHP and fuzzy comprehensive evaluation methods, although to a certain extent, multi-source The ambiguity and randomness of risk factors, but failed to express it well, and did not take into account the complex dependencies between risk factors in the shield construction process, so that the safety hazards in the construction process cannot be effectively It is also difficult to achieve better early warning and control of structural construction risks

[0004] During the shield construction of structures, the construction environment is complex and changeable, most of the environmental factors will change and update with time and space, and there are many risk factors and strong correlations in the construction process, and there are still large uncertainties, which makes the shield The construction safety risk assessment of structures passing through existing structures has become a complex dynamic decision-making system

Images