A Study on Stabilization Effect of the Acid Sulfate Soil by Using Crushed Oyster Shell

Abstract

Excavating the ground which consists of the marine deposits formed during Neogen and/or Quaternary period, the acid sulfate soil occasionally appears on the execution basis. As this soil includes sulfuric acid produced with the oxidation of sulfide, the growth of plants is disturbed and it becomes difficult to improve the soil by adding a stabilizer. In general, the calcic materials such as stone powder and zeolite have been employed to neutralize the acid sulfate soil from the past. Therefore, the shells which are composed mainly of a calcium carbonate can also be considered to be useful as a material for the neutralization process. We have ascertained the stabilization effect due to the using of crushed oyster shell by comparing the amount of swelling and CBR value for soil-stabilizer-shell mixture with those for soil-stabilizer mixture. Mixing crushed oyster shell into the soil, pH value of the mixture gradually shifted to neutral with elapsed time and its water content decreased immediately. Furthermore, the amount of swelling which occurred during submergence curing was extremely small for soil-stabilizer-shell mixture and CBR value of this mixture was 1.5 to 4 times larger than that of soil-stabilizer mixture. These results indicate that both surplus soil and non-industrial waste will be utilized effectively as embankment and subgrade materials at a time.

Transesterification of soybean oil using combusted oyster shell waste as a catalyst

“…In most cases, the waste has often been left untreated for a long time in the field, giving a nasty smell. To reduce the amount of oyster shell waste, researchers have investigated its use as a construction material (Yoon et al, 2003), a stabilizer of acid sulfate soil (Yamada et al, 2005) and an adsorbent for phosphate (Namasivayam et al, 2005).…”

Bivalve Shell: Not an Abundant Useless Waste but a Functional and Versatile Biomaterial

“…Therefore, shell waste can be considered an adequate substitute for the neutralization process. Yamada et al [77] studied the stabilization effect of crushed oyster shell on acid sulfate soil by comparing the amount of swelling and the california bearing ratio (CBR) value for soil-stabilizer-shell mixture with those for a soil-stabilizer mixture. Mixing oyster shell into the soil caused the water content of the mixture to decrease immediately and its pH value to shift gradually to neutral.…”

Effect of Biowaste on the High- and Low-Temperature Rheological Properties of Asphalt Binders

“…In the field of biomedicine, oyster shells have been used for the development of anti-ACE competitive inhibitors [9]. In the field of environmental science, oyster shells have been used for marine environment remediation [10] and improvement of acidic sulfate soils [11]. In the field of food science, oyster shells can be used to make preservatives [12] and additives for food products [13].…”