Monitoring method for karst tunnel structure safety warning

Abstract

The invention discloses a monitoring method for karst tunnel structure safety warning. The method includes: monitoring the rainfall situation of a tunnel area in real time through a rainfall monitoring system; acquiring the lining structural internal force (including the lining surface stress and the lining structural stress) through a structural internal force monitoring system; transmitting thedata obtained by the rainfall monitoring system and the structural internal force monitoring system to a data platform through a wireless network, and processing the data by using a data analysis andprocessing system; establishing a database of the rainfall parameters and the lining structural internal force; selecting a suitable neural network model to train and learn samples in the database; and establishing a relation curve between the lining structural internal force and the structural safety degree, and pre-warning the structural safety according to a structural internal force change trend value predicted in advance by the neural network prediction model and a structural full life curve. The invention provides an early warning. The monitoring method ensures the structural safety of the tunnel and provides a guarantee for the safe operation of the karst tunnel.

Description

technical field [0001] The invention relates to a structure safety early warning monitoring method, in particular to a monitoring method for karst tunnel structure safety early warning. Background technique [0002] In recent years, under the condition of heavy rainfall, tunnel catastrophes caused by changes in tunnel water pressure in karst areas often lead to the occurrence of railway line breaks, seriously affecting the normal operation of railways, and bringing great safety hazards to railway operations in rainy seasons. Especially in some karst tunnels in the western mountainous area, there are often low groundwater levels in dry seasons, and even no water pressure acts on the lining, or underground underground rivers make the water pressure on the lining structure relatively small. In the rainy season, continuous heavy rainfall will also cause the groundwater level in the tunnel site area to rise rapidly in a short period of time, and the water inflow in the tunnel wil...

AI Technical Summary

Problems solved by technology

In this case, for the existing tunnel, there will be structural uplift at the bottom of the tunnel, collapse, bursting and extrusion of the lining side wall, large-area lining cracks or cracking damage, large-scale water jetting and water leakage at the construction joints, etc., which are serious. Affects railway operations and brings great safety hazards to railway operations in the rainy season

[0003] Taking the Chengdu Railway Bureau as an example, from 2014 to 2016, six tunnels in the management section of the Chengdu Railway Bureau experienced problems such as tunnel bottom uplift, water seepage in the tunnel, and side wall lining collapse during the rainy season, which affected the structural safety and operational safety of the tunnel ( Defects), the lighter ones only damage the structure, and the heavier ones affect the passage of trains, and even cause outages

The geological conditions of karst tunnels are complex, and the distribution of karst pipelines is difficult to detect. It is difficult to quantify the impact of changes in the hydraulic pathways of karst caves on the tunnel structure caused by tunnel construction. The influencing factors are unknown. The impact of changes in external conditions such as heavy rainfall and surface water runoff on the structural stress Quantitative calculations are also impossible, which makes it difficult to guarantee the safety of the karst tunnel structure during operation, and brings potential safety hazards to the tunnel operation

Safety monitoring is carried out by directly laying out measuring points on the structure, and there is often a lag in the safety early warning of the structure. Therefore, based on the characteristics of karst tunnels under heavy rainfall conditions, there is a lag in the safety early warning of conventional safety monitoring methods. Sexual Disadvantages

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