Rock mass damage monitoring method in rock foundation pit excavation process

Abstract

The invention relates to a rock mass damage monitoring method in a rock foundation pit excavation process, and the method specifically comprises the steps: carrying out the three-dimensional numericalsimulation of a foundation pit, and determining a micro-seismic monitoring region through combining with the monitoring information in a construction process; in a monitoring area, preliminarily determining X micro-seismic sensor arrangement schemes, and selecting an optimal arrangement scheme through a large number of simulation experiments; installing the determined sensor arrangement position;placing a micro-seismic monitoring base station at the upper part of the foundation pit; connecting the installed micro-seismic sensor to a monitoring base station through an optical fiber; after themicro-seismic sensor is installed, performing a blasting positioning test, debugging system parameters, and checking positioning errors; and evaluating the current rock mass damage degree of the foundation pit according to the monitoring data of the micro-seismic base station. According to the method, the micro-seismic monitoring technology and conventional detection are combined, the slope blasting excavation loss area can be rapidly and accurately determined, the rock mass blasting influence range is reasonably and effectively controlled, and the method has important significance in ensuring construction safety and preventing foundation pit instability.

Description

technical field [0001] The invention belongs to the field of geotechnical engineering, and in particular relates to a rock mass damage monitoring method during the excavation of rock foundation pits. Background technique [0002] During the blasting excavation of rock foundation pits, the explosive load will inevitably cause dynamic damage to the retained rock mass while completing the blasting and crushing of the rock, forming the so-called excavation damage zone. During the construction period, the damage area was continuously evolved and expanded due to unfavorable factors such as subsequent excavation disturbance and rainfall, which was very unfavorable to the local and overall stability of the slope and construction safety. Especially as the excavation depth of the foundation pit continues to increase and the foundation pit becomes higher and steeper, it is necessary to strictly control the impact of excavation and blasting on the stability of high slopes. There are co...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problem that the damage degree of rock mass cannot be monitored in real time during the excavation process of rock foundation pit, and proposes a method for monitoring rock mass damage during the excavation process of rock foundation pit. Combined with conventional detection, it can use the microseismic signals generated during the rock fracture process in rock foundation pits to determine the spatial location, occurrence time, rupture mode, and release energy level of rock mass rupture, and use these information to judge potential rock mass. The law of disaster activities in foundation pits, and the evaluation and analysis of the stability of rock mass

Images