Risk Assessment of Deep Foundation Pit Construction Based on Analytic Hierarchy Process and Fuzzy Mathematics

Abstract

The construction risk of deep foundation pit (DFP) engineering is high, and accidents occur frequently. It is necessary to evaluate the risk of deep foundation pits before construction. At present, although there are many risk assessment methods, there is not one with strong applicability and high accuracy. Based on expert scoring, this paper analyses the risk from two aspects (the severity of consequences and the probability of occurrence), divides the severity of the consequences into five indexes, calculates the risk by using the analytic hierarchy process (AHP), and sets the expert weight index so that the subjective expert scoring result can obtain the best possible objective calculation result. In addition, this paper uses the membership function from fuzzy mathematics to establish the level of risk and optimize the evaluation criteria of risk events. An engineering example is introduced, and the result of the risk assessment shows that the evaluation result R (risk value) obtained by the optimized risk assessment method in this paper is 7.9 and that the level of risk is grade III. The risk assessment method proposed in this paper has strong applicability and can obtain more accurate evaluation results. This method can provide a reference for the risk assessment of deep foundation pit engineering.

Risk Identification and Assessment during the Excavation of the Deep Foundation Pit

“…U32, U31, and U34 are of high importance in the whole risk index system. e subjective weight of each index can be obtained by (10), as shown in Figure 7 3.4. Objective Weight.…”

“…Wang and Chen [9] combined the fuzzy comprehensive evaluation method and the Bayesian network to evaluate the risk of foundation pit project from three aspects of risk probability, loss, and controllability. Meng et al [10] used analytic hierarchy process and fuzzy set theory to evaluate the risk of foundation pit supporting. Deng et al [11] used the fuzzy analytic hierarchy process to determine the risk level of subway deep foundation pit construction and put forward the corresponding risk control measures.…”

“…Meng et al [10] used analytic hierarchy process and fuzzy set theory to evaluate the risk of foundation pit supporting. Deng et al [11] used the fuzzy analytic hierarchy process to determine the risk level of subway deep foundation pit construction and put forward the corresponding risk control measures. e introduction of fuzzy set theory expands the application of evaluation methods in uncertain environment, but it is also very important to reasonably calculate the weight of indicators.…”

A dynamic assessment method on collapse risk of small spacing tunnels based on attribute interval recognition model

“…The basic idea of the AHP (Jafar et al 2010;Meng et al 2020;Saaty 1977;Wu et al 2021) is to decompose the evaluation index of the evaluation object, establish a hierarchical structure, compare multiple factors in pair, and quantify the qualitative problem. What's more, AHP can make full use of expert experience in weight calculation of evaluation indexes, which improves the rationality and effectiveness of decision making to some extent (Chen et al, 2020).…”

Risk Assessment of Constructing Deep Foundation Pits for Metro Stations Based on Fuzzy Evidence Reasoning and Two-tuple Linguistic Analytic Network Process

“…Constructing deep foundation pits (DFPs) is an essential but high-risk part of any urban rail project, and the uncertain factors in the construction process are the essential reasons for the risks in metro DFP construction. During the construction of a metro DFP, complex geological conditions and the surrounding environment often lead to large-scale destructive accidents [1,2]. For example, while constructing Xianghu station on Line 1 of Hangzhou Metro in 2008, the DFP collapsed because of severe overexcavation and failure of the supporting system, resulting in more than 20 deaths [3].…”