Assessment of In-Situ Test Technology for Construction Control of Base Courses and Embankments;Final rept. Jul 01-Dec 03

摘要

With the coming move from an empirical to mechanistic-empirical pavement design, it is essential to improve the quality control/quality assurance (QC/QA) procedures of compacted materials from a density-based criterion to a stiffness/strengthbased criterion. The non-destructive in-situ tests such as the Geogauge, Dynamic Cone Penetrometer (DCP), and Light Falling Weight Deflectometer (LFWD) can be effective tools for assessing of subsurface conditions and evaluating the stiffness of pavement materials and embankments. This report evaluates the potential of these three devices to reliably measure the stiffness characteristics of highway materials for possible application in the QC/QA procedures during and after the construction of pavement layers and embankments. To achieve this, field and laboratory testing programs were conducted. The laboratory program included construction of different sections inside two boxes (5x 3x 2.5ft.) located at the Geosynthetic Engineering Research Laboratory (GERL) at the Louisiana Transportation Research Center (LTRC). The field tests were conducted on highway sections selected from various projects in Louisiana. In addition, six test sections and three trench sections were constructed and tested at the LTRC Pavement Research Facility (PRF) site. The field and laboratory tests included Geogauge, LFWD, and DCP tests in conjunction with two standard tests such as the Plate Load Test (PLT) and Falling Weight Deflectometer (FWD) test. The California Bearing Ratio (CBR) laboratory tests were also conducted on similar samples collected during the field and laboratory tests. A statistical analysis revealed good correlations between the measurements obtained from the three investigated devices and those obtained from the standard tests, thus demonstrating that the investigated devices can reliably measure the in-situ stiffness of highway materials, subgrades and embankments.