Studies On The Monitoring System Of Roadbed Embedded By Construction Wastes

In order to realize the recycling of construction wastes, the Shaanxi Provincial Transportation Construction Group, cooperating with Chang’an University, has carried out a project about "the research on the key techniques of comprehensive utilization of construction wastes on a large scale" in the construction of the north loop of Xi ’an-Xianyang freeway. In this paper, based on the project, the author built an automated monitoring system of roadbed embedded by construction wastes at a test section. The system could real-timely, chronically and precisely monitor the data of subgrade settlement to explore the subsidence rule of this kind of roadbed, when the subgrade was under construction and after construction.The system built by the combination of sensor technology, microcontroller technology and GPRS technology, etc.consists of a leading part, including data measurement modules, data acquisition modules, data transmission modules and a power module, and a back part, referring to a monitoring center in background. The data acquisition module sends instructions to the data measurement module regularly. The data measurement module that received the constructions gathers the corresponding information about the subgrade settlement and transfers the data to the data acquisition module, which conducts the preliminary processing and storage of the data. Then the data transmission module transmits the data to the monitoring center in background through the GPRS network remotely. Appropriate powers needed by the system are provided by the designed assistant power module. The monitoring center in background builds a database based on the received data to store and process the data and display them dynamically in the computer page. The measured settlement data, combining the hyperbolic method as the prediction method and MATLAB software, are used to do some computations and analyses to verify the subsidence rules, the comparison result of the system’s data indicates that the system operates well and satisfies the monitoring claims and the settlement rules of the monitoring data accords with the prediction of the theoretical analyses.The system has realized the remote and automatic monitoring of the subgrade settlement data, making up for the study blank on the recycling of construction wastes in subgrade. It provides some design bsises to other similar systems and has some practical value in engineering.