STUDY ON USING VERTICAL DRAIN MADE FROM NATURAL MATERIALS TO SPEED UP CONSOLIDATION RATE OF THE SOFT SOIL LAYER

Abstract

It is well-known that soft soil treatment technology using prefabricated vertical drain (PVD) combined with preloading is widely used in soft soil areas in Vietnam and around the world. In the role of soft soil treatment, the function of PVDs is that accelerates the consolidation rate and increases the shear strength of the subsoil. In practice engineering, the PVDs have been manufactured from polymeric prefabricated vertical drains, so there has recently been considerable interest in their environmental effects in the soil and groundwater levels below the construction. In this paper, the authors propose to use a waste natural material such as fibrous material such as coconut fiber to perform the function of vertical drainage as conventional PVDs. This research proposal aims to take advantage of available materials, common in Vietnam, with high biodegradability, thereby improving the environment in the soft soil improvement. To carry out the research, the authors will perform a serious consolidation experiments of soft soil column in the laboratory with various conditions such as: soil column installed by conventional PVDs; soil column installed by natural PVDs (using the coconut fiber) and soil column without drainage installation. Experimental results show that coconut fiber waste material can be used to drain as well as the current PVDs. The research results serve as a premise for further studies on the use of natural PVDs in production and application conditions in Vietnam.