A Dynamic Inversion Analysis Method for Soil Parameters Applicable to Suspended Deep Foundation Pit Engineering

Abstract

The invention provides a soil parameter dynamic inversion analysis method suitable for suspended deep foundation pit engineering, which can optimize the inversion parameters cyclically and apply the optimized parameters to numerical simulation prediction. According to the on-site monitoring situation and parameter sensitivity analysis, the inversion target and inversion parameters are determined. For multi-variable problems with multiple soil layer parameters and multiple excavation steps, by calculating the interval influence coefficient and introducing soil layer weights and excavation step weights, the multi-variable problems are transformed into univariate problems, and the least square method is used to solve the problem. Interval optimization analysis to determine the optimal parameters of the soil. In the present invention, the foundation pit excavation sequence is used as the back-analysis progressive sequence, and the parameters are carried out in the circular calculation and analysis of "inversion-prediction-re-inversion-re-prediction", and the dynamic inversion and Correct the soil parameters, apply the optimized parameters to the numerical simulation prediction, compare the actual monitoring values, verify the feasibility of the back analysis method, and provide early warning for the construction of suspended deep foundation pit engineering, which has high application value.

Description

technical field [0001] The invention relates to a soil parameter inversion method, which relates to the fields of geotechnical engineering and tunnel engineering, and specifically relates to the field of deep foundation pit engineering. Background technique [0002] When supporting the foundation pit, a drop-bottomed enclosure structure is usually selected and extended into the water-resistant bottom plate to cut off the hydraulic connection between the inside and outside of the foundation pit. The suspended enclosure structure cannot penetrate the aquifer. During the excavation of the foundation pit, the precipitation in the pit will cause the water level outside the pit to drop, which in turn will lead to uneven settlement of the surrounding surface or swelling of the pit bottom, and cracks and settlement of surrounding buildings. In order to ensure the safety of the foundation pit and its surrounding environment, foundation pit monitoring methods are usually used to grasp...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to provide a dynamic inversion analysis method of soil parameters suitable for suspended deep foundation pit engineering, which solves the problem that the existing foundation pit monitoring technology is difficult to predict the risk position in advance and there is a construction safety risk, And when the traditional numerical simulation method is applied, the results of a test usually used to determine that there is a large deviation between the soil layer parameters and the actual data. The introduction is based on the monitoring situation and parameter sensitivity analysis to determine the inversion target and inversion parameters. By calculating the interval Influence coefficient, introduce soil layer weight and excavation step weight, transform multivariable problem into single variable problem, and use least square method to carry out interval optimization analysis to determine the optimal parameters of soil, and excavation sequence of foundation pit as inverse Analyze the progressive sequence, carry out the cyclic calculation and analysis of "inversion-prediction-re-inversion-re-prediction" on the parameters, continuously invert and correct the soil parameters dynamically with the increase of the excavation depth and the number of soil layers, and apply the optimized parameters Based on the numerical simulation prediction, combined with the monitoring data in the actual project, the model is repeatedly optimized, and the parameters are dynamically adjusted. The invention has a wide range of applications and provides effective early warning for the construction of suspended deep foundation pits, so that the construction can avoid risks within a reasonable range

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