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 CaCO3
and SiO2. 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 0C
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.