Monitoring catastrophic ground collapse of urban roads with permanent curbside electrode arrays

Abstract

Active underground constructions and leaking utility pipelines in urban areas can seriously undermine the foundation of roads. Deadly collapse of road surface may suddenly happen if the soil under pavement is washed away. This paper proposes a permanent and economical monitoring approach based on the electric resistivity method. By exploiting the intrinsic volume effect in electric exploration, electrode arrays installed on curbside can be used to detect developing cavities beneath road surface. I present a fast survey scheme with the ability of focusing current paths on high-risk areas. This new method is numerically tested on some synthetic resistivity models that are snapshots of a randomly-grown cavity at a road intersection. The modelled data show that decent data anomalies can be measured at favorably-coupled electrode positions, and the daily variation of the acquired electric field data may forecast the critical moment of pavement failure. The numerical results encourage further field work to be carried out to validate this curbside monitoring idea.