Munehiro MATSUI, Jun’ichi KURIHARA, Nagazumi TAKEZAWA and Koji IIZUKA
Abstract
SABO soil cement method is to utilize site generated soil as material. INSEMiIN]situ Stabilized Excavation Materialsjmethod is one of the SABO soil cement method. Construction method of INSEM is to screed and compact the material that is made by mixing site generated soil with cement powder, and to construct SABO structures. Because of the advantages, such aspect as cost, environmental and workability etc., applying of INSEM method is increasing in the field of SABO works in recent. However, basic characteristic of INSEM is not always clear enough. One of them is hexavalent chromium elution from INSEM.
There are several reports that hexavalent chromium elution from INSEM exceed the limited value(0.05mg/L) regulated by Environmental standards on soil pollution formulated by Environment Agency. If such incident takes place after initiation of construction, unexpected time is consumed for managing to decrease hexavalent chromium elution value or even to modify the construction method itself, resulting serious influence to term of work or cost.
Expecting more widely use of INSEM method that have many advantages in terms of zero emission, environmental and cost merit, it is necessary to clarify characteristic of chromium hexavalent elution from INSEM as well as coping strategy to decrease excess value of chromium hexavalent elution.
This study is to clarify characteristic of chromium hexavalent elution from INSEM and coping strategy by making use of different type of site]generated soil and changing amount of cement use in indoor examination.
From results and considerations of study, it is found that to power up sufficiently reaction of cement for solidification is important as a fundamental coping policy, when excess value of hexavalent chromium elution from INSEM is found.
Key wordsFINSEM (IN]situ Stabilized Excavation Materials), hexavalent chromium elution, environmental standard on soil polution 2001