Studies on effect analysis of different exploration methods for karst collapse detection in the periods of rainy and dry seasons

Abstract

Karst collapse geological disaster seriously restricts the social development. Due to its sudden and concealment, it is of great significance to take effective methods to accurately identify the potential collapse location for the scientific and reasonable prevention and control of karst collapse. In this study, a typical area in Wuhan was taken as an example to compare the karst collapse detection effects of three exploration methods, namely ground-penetrating radar (GPR), high-density resistivity method, and cone penetration, in rainy and dry seasons, providing reference for the selection of karst collapse exploration methods under hydrodynamic condition changes. The results show that the GPR has a good response to the disturbed soil within 4 m at the frequency of ≤100 MHz. The detection depth of 40 MHz GPR is deeper, and the abnormal response of the disturbed soil detected by 100 MHz GPR is clearer in dry seasons than that in rainy seasons. The high-density resistivity method describes the stratigraphic structure more accurately in rainy seasons than in dry seasons, and is adaptable for the detection of shallow and middle rock and soil structure. There is no significant difference between cone penetration in the period of rainy and dry seasons, while that is suitable for soil detection within 10 m, especially for delineating the boundary range of the subsidence area.

Keywords

• karst collapse
• ground penetrating radar (gpr)
• high-density resistivity method
• cone penetration
• hydrodynamic condition
• stratigraphic structure