Effect of Cycle of Loading on Subbase Friction Charisaritics Under Rigid Pavement

Abstract

The coefficient of friction is a measurement of the frictional force between two objects. As the temperature of the pavement changes, it might slide against the resistance of the supporting subbase. In order for pavement to perform as anticipated, this resistance must be calculated. Concrete cracking does not occur when the pavement is joined. A membrane layer is positioned between the subbase and the plate in joint plain concrete pavements to smooth the interface. The displacement of concrete caused by temperature differences is less resistant on a smooth surface. For subbase conditions, two stages of the push-off test were performed (smooth and rough) to show the effects of movement cycles. Based on the results of the friction tests, the friction properties of the concrete and subbase were investigated. The parameters that influence the coefficient of friction and displacement are (interface state, movement rate, thickness number of movement cycles), changing the interface condition from smooth to rough leads to an increase the FRF of (6, 9 and 12 cm/hr) by (194.7, 194.4 and 189.8 %) respectively. Finally, once the applied force reaches a stable state, the frictional force increases dramatically. The most important influence on this force is the interface state, which is accompanied by movement rate and thickness. The variation of the relationship curves with number of cycles tends to be insignificant after the third to fourth cycle of slab movement.