Abstract:
Rigid inclusions are a ground improvement technique that provides soil reinforcement and settlement mitigation using drilled displacement elements. Rigid inclusion installation typically uses a Monitoring While Drilling (MWD) electronic logging system that captures data such as torque, downward thrust, rotary speed and grout take with depth and time. Automatically generated graphic logs are typically reviewed visually by members of a project team for quality control during and after installation. This workflow underutilizes the valuable data provided by these MWD systems.
This paper discusses the use of MWD installation data integrated with cone penetration test (CPT) data and static load test results to develop a streamlined and robust quality control workflow for rigid inclusions. A compound parameter designated Integrated Resistance Index (IRI) is computed using soil-tool interface mechanics principles for each production element and compared with the IRI for load test elements to rapidly assess the suitability of production elements. This method can be used to determine whether optimization of the intended lengths is possible or where a more intense treatment may be necessary in specific areas of the site. This quality control workflow can be performed in near-real time.