Experimental Study of Physical Models for Sinkhole Collapses in Wuhan, China

Many sinkholes collapsed since 1998 in Wu Han, China. Sinkhole collapses have put local people's properties and safety in great danger. This paper introduces a large-scale experimental study to implement physical models of sinkhole collapse in this area. Two conceptual models of sinkhole collapsing have been established based on the processes of sinkhole formation, basic geologic conditions, hydrodynamic features, and human activities in this area. Rock, soil, and water samples from sinkhole collapsing areas have been used for a large-scale experiment to verify the conceptual models. High resolution fluid pressure transducers and soil pressure transducers were used in the experimental study to monitor pressure changes in fluids and soil. Measurements of pressure changes were automatically collected and inspected during the experiment. Quantitative studies of Quaternary groundwater use, karst water use, Quaternary soil texture and structure, and the size of the pipelines of karst openings have been conducted to investigate their relationships with the sinkhole collapsing processes. The threshold values of dominant physical properties to trigger a sinkhole collapse have also been studied in this area. Results from this research project provided important information and guidelines on how to prevent future sinkhole collapse in this area.