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| Large-scale experimental study of multi-layered reinforcement to prevent underneath sinkhole in karst terrain and the design method |
| HE Wei1，2，LI Kun1，WANG Fanghong1 |
(1. School of Civil Engineering and Architecture，Changsha University of Science and Technology，Changsha，Hunan 410114，China；
2. Co-Innovation Center for Advanced Construction and Maintenance Technology of Modem Transpotation Infrastructural Facility，Changsha University of Science and Technology，Changsha，Hunan 410114，China) |
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Abstract To prevent the underneath collapse induced hazard in road transportation，the multi-layer geotextile reinforcement is a cost-effective and promising technology，although its bearing mechanism and design method remain to be further studied. The embankment models of 1∶5 in scaling，with the single-layer，three-layer and four-layer geotextile reinforcements installed respectively，were designed and tested in laboratory. In order to study the load distribution and displacement characteristics，the vertical pressure on each geotextile and the relevant displacement were measured with the load cells and deformeters installed in the model. The key issues in design and the relevant calculation theory were discussed based on the measured data. The test results revealed that，in multi-layered geotextile reinforcement，the foot of soil arch might rise to around the top-layer reinforcement，and the dual-soil-arch emerged. The upper load distributed non-uniformly among the reinforcements. The surface depression could be related to the bottom deflection with a simplified method ignoring the dilation effect. The bottom-layer reinforcement is the key to control the surface depression while the top-layer is of the most importance to control the limit state. Based on the measured data and further analysis，a flow chart of design was proposed for practical engineering application.
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2016, Vol. 35 
