Permeability of A Composite Seawall: Effect of the Orientation of Gaps in the Structure

A Seawall requires reflecting and dissipating entire wave energy with zero transmission. The permeability would significantly affect its hydraulic stability under wave loads. Thus, the permeability of a structure changes with the material and consequently a variation in the composite structure may give a different perspective on the hydraulic performance of a seawall altogether. As a first step towards establishing the composite seawall, a comprehensive permeability test is performed as a preliminary assessment of hydraulic conductivity. In the current research, a bag made of non-woven geotextile polymer filled with sand and a roll of non-woven needle punched coir geotextile is investigated. A total number of 20 model tests were performed by varying the orientation and positions of the material composites and thereby the gaps in the structure. The results are noted and future research possibilities into the design and development of a composite seawall as an alternative to traditional seawall are thus presented.