Deep Excavation
1. Monitoring Background
With the rapid development of the city, the buildings are longer and higher, and the safety of the essential foundation pit project has always been a special concern of the public. However, in recent years, the foundation pit engineering accidents continue, mainly for the destruction of the enclosure structure, foundation pit collapse and large-scale landslides, foundation pit around the road cracking and collapse, adjacent underground facilities displacement and destruction, leading to the construction (structure) building cracking and collapse, resulting in a significant loss of life and property. According to statistical data, it is found that almost all foundation pit accidents are directly related to poor detection or inaccurate prediction of dangerous situations. If we can carry out effective safety monitoring of the foundation pit enclosure structure, so as to give an assessment of the health status of the foundation pit enclosure structure, and give an early warning before the disaster, it will greatly reduce the occurrence of accidents.
For complex large and medium-sized projects or projects with strict environmental requirements, it is often difficult to learn from past experience, and it is difficult to find quantitative analysis and prediction methods in theory. Therefore, in order to ensure the stability of the foundation pit structure, timely understanding of the underground water level, underground pipelines, underground facilities, ground construction in the excavation of the degree of influence, the establishment of (deep) foundation pit engineering safety monitoring system is very necessary.
2. System Overview
The construction risk of foundation pit excavation is high and the construction is difficult. A large number of engineering practical experience and theoretical analysis show that there are many reasons for the occurrence of risk, both internal and external factors, and the complexity of the surrounding environment of building construction (such as buildings, roads, underground pipelines, etc.) is one of the key external factors.
The main technical parameters of traditional testing are measured by manual and regular use of traditional instruments to the site, the safety testing workload is large, affected by the weather, labor, site conditions and many other factors, there are certain system errors and human errors. At the same time, manual detection still has the shortcomings of not being able to detect the technical parameters in time, and it is difficult to grasp the safety technical indicators of the project in time, which affect the safety production and management level of the project.
The implementation of the automatic monitoring system of the foundation pit enclosure structure and important buildings (structures) is convenient for the construction unit and the safety supervision department to quickly grasp the latest developments of the technical indicators closely related to the safety of the project, and is conducive to timely grasp the operation status and safety status of the project.
Main monitoring contents
Monitoring basis
(1) Code for Design of Buildings (GB50352-2019);
(2) Code for Building Deformation Measurement (JGJ8-2016);
(3) Code for Engineering Survey (GB55018-2021);
(4) Technical Code for Monitoring of Building Foundation Pit Engineering (GB50497-2019);
(5) Code for Investigation of Geotechnical Engineering (GB50021-2009);
(6) Standard for Engineering Rock Mass Classification (GB50218-2014);
(12) Other relevant national or industrial norms and mandatory standards;
(13) Relevant construction design drawings of foundation pit.
System function
Data acquisition and transmission function
The equipment of data acquisition and transmission system of our company mainly includes: data acquisition instrument, serial port server, A/D conversion equipment, transmission cable and wireless data transmission module. For each monitoring sub-item, the information collection and transmission node will be arranged according to the on-site environment of the structure, and the real-time data obtained by various parameter sensors will be uploaded to the central server host through the wireless data transmission module for data recording and analysis.
Reserved manual port for data collection and transmission
When manual monitoring is required, our company's data acquisition and transmission system still has a transmission port for manual portable acquisition instrument, which can collect data manually.
Data analysis function
The monitoring and analysis option is to organize the data collected and returned by all devices on site and display them in the system according to time. The system will self-diagnose the data to determine its validity, mainly by comparing the same group with historical data to see if it is a single mutation value. For effective data, the system will sort out and analyze the classification, and users can view and analyze the data they need.
Monitoring and early warning function
According to the different range of monitoring and control indicators, the early warning is divided into three levels for monitoring process management, and the monitoring data is compared with the three-level early warning value to determine the monitoring and early warning level of the site.
Information push function
Our online monitoring system works 24 hours a day without interruption. In case of abnormal conditions of structures, it will send early warning information to the user's mobile terminal. According to different alarm levels added by the user, the system will automatically send short messages according to the alarm level.
Report production function
The user can carry out to check out the data report export, after the user enters the system, you can download the data you need.
