Using Compaction Equipment Instrumented with Global Positioning System (GPS) Technology to Monitor Field Lift Thickness: Fid-Bau Portal

Using Compaction Equipment Instrumented with Global Positioning System (GPS) Technology to Monitor Field Lift Thickness

Cacciola, Daniel V. / Khosravi, Mohammad / Meehan, Christopher L.

During the construction of earthen embankments, it is essential that the fill material be spread in uniform lifts prior to compaction. Current compaction specifications typically place restrictions on the maximum soil lift thickness to ensure that the soil may be uniformly compacted to reach the required density. In current practice, a single field inspector is responsible for enforcing this lift thickness criterion while soil is being placed and spread over large compaction areas. Using this process, it is nearly impossible for a field inspector to accurately measure the thickness of the soil throughout the entire compaction area. This can lead to later performance issues for a constructed embankment that are largely related to the occurrence of nonuniform soil compaction. Innovative compaction verification techniques such as continuous compaction control (CCC) and intelligent compaction (IC) systems have been developed, which provide real-time monitoring and feedback about the operation and performance of soil compaction. Typically, these CCC/IC systems are retrofitted with a real-time kinematic global positioning system (RTK-GPS) that monitors and records the position of the compacter as the soil lift is being compacted. This paper explores the use of field RTK-GPS measurements that are made by CCC equipment to monitor and control the thickness of compacted soil lifts. A simple spatial analysis technique is examined for interpolating field measured elevation data onto a uniform grid for lift thickness assessment. The approach that is presented can be used to build spatial maps of compacted soil lift thickness, which are a useful decision-making tool for field inspectors.