Nondestructive measurement of depths of earthing, canal lining and roadbed of reclamation projects

The scope of damaged land caused by coal mining is increasing every year. For the sake of relieving the conflict between population growth and land availability, lots of land reclamation projects have been imposed in many provinces of China. However, the quality examination of those projects, which is considered as a key basic safeguard, always uses traditional methods. Few studies have reported on quick, non-destructive, and comprehensive engineering quality-testing methods. In order to overcome the deficiencies of quality inspection and evaluation in land reclamation projects, a variety of high frequency ground-penetrating radar GR-Ⅲ systems has been used to detect the projects of covering, field canal and production road of the land reclamation in Ganshui town, Chongqing city, all the response characteristics of radar signal had been revealed. Using the energy changes of each sampling channel in different regions of radar image, the horizon identification algorithm was represented, which was used to resample the feature points of each horizon in different projects. On this basis, key factors of project quality, such as the depths of covering, field canal lining, and concrete pavement of production roads were calculated by different estimation methods using electromagnetic wave velocity, which were also considered as the indexes of the new evaluation model of reclamation project quality. The results show that GPR can realize nondestructive testing of land reclamation project quality and obtain comprehensive data. The detection effectiveness is positively correlated with the antenna's center frequency. The final evaluation result shows that qualities of the covering project and production road are classⅡand I, respectively. They meet the needs of farmland production, but the quality of field canal lining is class Ⅲ, which must be thicker in later work. This study could provide a new way and a scientific basis for the evaluation of land reclamation project quality.