Most maintenance activities on continuously reinforced concrete (crc) pavements are related in one way or another to punchout distress. Over several years of observation of crc pavement, several symptoms related to the structural aspects of punchout distress have beennoted. These symptoms include, but are not limited to, close crack spacing, surface widening and spalling of transverse cracks, development of longitudinal cracking, loss of load transfer, and subbase and subgrade pumping. Literature reviews have elaborated on punchout-related factors with respect to pavement performance. However, the punchout mechanism relating the various factors is not completely defined. Some questions exist concerning the sequence of events leading to the loss of load transfer across transverse cracks as a prerequisite to the development of a punchout. This sequence of events relates to the role reinforcement plays in the punchout process and whether the loss of aggregate interlock requires rupturing of the steel. If rupturing of the steel occurs, the question is whether rupturing occurs before or after the loss of aggregate interlock. Factors related to punchout distress as noted by this investigation and others are reviewed and a possible mechanism of punchout distress is addressed. This paper appears in transportation research record no. 1286, Design and evaluation of rigid and flexible pavements 1990.
Samenvatting