On-site simple method for recycling of excavated soil and its compaction characteristics for water pipe laying works

摘要

When laying water pipelines, excavated soil is generally disposed and replaced with commercially available sandy material. Reuse of the excavated soil yields reduction of both the environmental loads and the construction costs. Although “The guideline for use of excavated soil” by Ministry of Land, Infrastructure and Transport, specifies reusable soil types, it is not common practice to use the excavated soil for the laying of water pipeline because the specification requires complicated laboratory soil tests for the judgement. In this study, the applicability of the on-site simple method, called the “FK method”, is evaluated through a series of laboratory tests and model tests by using soil samples collected from various regions in Japan. As a result, the FK method successfully indicated compaction characteristics and bearing capacity of excavated soil. Hence, the method can be used on-site to judge the availability of excavated soil for water pipe laying works.