Correlation of LWD, CBR and Cyclic-Triaxial Tests

Authors
1 K .N. Toosi University of Technology
2 Science and Research branch, Islamic Azad University
Abstract
The resilient modulus of subgrade is an important factor in pavement design which is
determined by cyclic triaxial test on cylindrical samples. Due to test complication and
difficulties, other tests could be useful if there is an appropriate correlation between results.
Nowadays non-destructive testing of pavement is growing in the world as they are rapid,
without destruction and have precision measuring equipment. In recent years the application
of LWD has been widely developed. This device evaluates pavement structure of several
locations in short time with high accuracy. The main objective of this paper is to evaluate the
LWD feasibility in order to estimate subgrade resilient modulus and the quality control of
construction. So the in-construction road path have been chosen, then LWD field test, CBR
laboratory test and finally cyclic triaxial have been done. Also the compaction percentage of
each point determined to compare with LWD results.
Comparing modulus obtained from LWD results to other test lead to establish models and
equation which the best relation between LWD modulus and resilient modulus acquired. Also
LWD result scattering is less than CBR. Moreover LWD device has enough efficiency for
structural evaluation of unbound material and quality control of pavement sublayers

Keywords


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