Artificial beachrock formation through sand solidification towards the inhibit of coastal erosion in Bangladesh

Abstract

Erosion is a great problem in the coast areas of Bangladesh. The present study was conducted through literature survey to evaluate the prospects of making artificial beachrock through sand solidification for the protection from coastal erosion in Bangladesh. On average, recession through erosion due to sea level rise (SLR) in the coast of Bangladesh will occur 0.87m per 1cm rise in sea level. Artificial beachrocks have the potentials to inhibit coastal erosion. Beachrock is a type of sedimentary deposit that generally occurs on tropical and subtropical beaches as a result of intertidal lithification of loose beach sands and gravels by carbonate cementation. Chemically, beachrock around the world differs in composition but mainly it composed of CaCO 3 and SiO 2. Beachrocks are cemented by high Mg calcite (HMC) with the influence on precipitation from seawater and/or seawater evaporation (PSW) and on surface microorganisms, bacterial ureolysis. On 30 °C curing temperature which is similar to the average temperature in Bangladesh beach sand solidified 5 to 8 MPa unconfined comprehensive strength (UCS) in 28 curing days using the ureolytic bacteria (Pararhodobacter sp.). It is concluded that it may be possible to manufacture artificial rocks through sand solidification similar to beachrocks for erosion control purposes in Bangladesh.