Effective Use of Dehydrated Sludge Sand of Returned Concrete

Abstract

In concrete construction, quantities of ready-mixed concrete are ordered in excess of the actual requirements. The surplus concrete returned to the plant without being unloaded is an unresolved issue. Accordingly, the effective use of the returned concrete is strongly desired. This study conducted physical and mechanical tests on the recycled sand made from sun-dried and classified the returned concrete sludge to clarify the properties of the recycled sand. Moreover, as a specific example of the effective use of recycled sand, the roadbed and frost heave suppression layer material are suggested, and several laboratory tests were conducted. As a result, sufficient applicability of the remaining concrete sludge recycled sand as roadbed material was determined. Furthermore, the results also showed that it is applicable as a frost-heaving suppression layer material.