Real-Time Measurement of Quality During the Compaction of Subgrade Soils
-
2012-12-07
-
Details:
-
Creators:
-
Corporate Creators:
-
Corporate Contributors:
-
Subject/TRT Terms:
-
Publication/ Report Number:
-
Resource Type:
-
Geographical Coverage:
-
Corporate Publisher:
-
Abstract:Conventional quality control of subgrade soils during their compaction is usually performed by monitoring moisture content and dry density at a few discrete locations. However, randomly selected points do not adequately represent the entire compacted area and could leave soft spots undetected. If not rectified, these soft spots can adversely affect the performance and longevity of the asphalt pavements constructed on top of the prepared subgrade soil. This report presents the findings of a study investigating the ability of the Intelligent Asphalt Compaction Analyzer (IACA), developed at The University of Oklahoma, to estimate the resilient modulus (Mr) of cementitiously stabilized subgrade soils in real-time during their compaction. Preliminary feasibility studies were carried out at two different sites in Year One of the study. These results were then used to develop calibration and estimation procedures for the IACA. The validation of the IACA was carried out at two different project sites in Year Two of the study. Virgin soil and additives from each of these sites were first collected and their properties were studied in the laboratory. Regression models were then developed to analyze the dependence of the subgrade stiffness (Mr) on the soil properties and level of compaction. Tests using Falling Weight Deflectometer (FWD) and Nuclear Density Gauge were conducted at select locations on the stabilized subgrade after compaction. IACA estimated Mr values were then compared with FWD backcalculated moduli and Mr values predicted using the regression models. The results of these tests reveal that the calibrated IACA can be used to estimate the resilient modulus of the soil in real time during compaction with an accuracy that is suited for quality control applications.
-
Format:
-
Funding:
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type: