Pervious Material Made from Landslide Debris for Road Base Construction

Abstract

Landslide is a common event for mountain roads in Taiwan. Among the landslides, some are up slope failure; others are down slope failure. For the former, a large quantity of landslide debris will be generated and then block the road traffic. It would be a good idea to move the debris from the up slope failure site to fill the lost road base resulted by the down slope failure. This paper will introduce an on-site mixing method to prepare pervious-CLSM (controlled low strength material) from the landslide debris by mixing it with proper amount of cement and water. Through the mixing process, the fine soils in the debris will flocculate to a sizable particles and/or stick to the surface of aggregates. As a result, the fines content of the debris can be eliminated and a pervious-CLSM is made. Through the binding effect of cement, the pervious-CLSM can also have moderate strength to maintain the stability of filled embankment and to sustain the traffic load as well. Together with geo-grid, a wrap-faced reinforced embankment as the road base can be constructed quickly using the site prepared CLSM as well as a backhoe machine and hand tools. After verified with a full scale embankment construction, the feasibility of building a pervious embankment in short time with the pervious-CLSM made from landslide debris has been confirmed. But the control of water content of the mixture on-site is crucial for this method.