JOINTED CONCRETE PAVEMENT FINITE ELEMENT MODEL DEVELOPMENT USING THE FWD DATA

In this paper, the authors use data collected through the Falling Weight Deflectometer (FWD) test to develop and validate finite element (FE) models for simulating pavement performance. FWD test data was chosen because to a great extent the test eliminates uncertainty about the load value and its placement on the pavement. The pavement construction and subbase conditions, at least at the time of construction, are also known. Thus, any discrepancies between computed results and actual field data can be attributed to the parameters in the FE models. For concrete pavements, accurate material properties can be obtained from the field and lab measurements, but the stiffness of the subgrade (k) cannot be determined directly. The FWD data is used to determine suitable k values using the FE models developed in this research. The load transfer across a doweled joint depends on a number of factors including dowel bar diameter, length, and spacing. These 3 variables are incorporated directly into the FE model. However, it is difficult to explicitly account for load transfer due to aggregate interlock at a joint. Using FE simulation of FWD tests conducted at the joints, suitable values were determined for this parameter.