Rapid evaluation of a transverse crack on a semi-rigid pavement utilising deflection basin data

Abstract

To evaluate the transverse crack on a semi-rigid pavement rapidly by a falling weight deflectometer (FWD), three-dimensional dynamic finite-element (FE) models were developed to calculate the deflection response of a transverse-cracked semi-rigid pavement under an FWD load. Models were validated by deflection basin data acquired from in situ FWD tests. Then, the effects of thermal cracking and reflective cracking on deflection basin data were analysed. Four loading locations and seven crack widths were considered in the analysis. Results showed that deflection basins calculated by dynamic FE models coincided well with that measured by in situ FWD test. The largest per cent difference between calculated deflections and measured values was less than 9%. When the distance between loading centre and crack was within 1050 mm, load transfer efficiency (LTE) indexes showed a good performance for distinguishing a reflective crack from a thermal crack. A practical field test method placing the transverse crack between sensor S₃₀₀ and sensor S₆₀₀ was recommended and LTE_300–600 was proposed as the evaluation index for the rapid determination of crack type.

Keywords:

• semi-rigid pavements
• transverse crack
• falling weight deflectometer (FWD)
• loading transfer efficiency (LTE)

Additional information

Funding

This work was supported by National Natural Science Foundation of China: [grant number 51778482].