Concrete Pavement Reliability by Monte Carlo Simulation

Abstract: The U.S. Department of Defense (DOD) seeks to elevate the importance of reliability of defense systems to perform their mission without failure or degradation. An efficient and effective methodology is proposed in this paper for assessing the inherent reliability embedded in the DOD airfield concrete pavement design process. Application of Monte Carlo Simulation and dimensional analysis results in a computer spreadsheet that requires little from a prospective user beyond a basic familiarity with commonly used commercial software. A surrogate procedure is developed capable of reproducing the results of DOD’s pavement design software (PCASE), in a manner that requires only a handful of PCASE executions, and eliminates the need for the software in each of the thousands of simulation cycles. Results obtained show that the design reliability within the PCASE software varies only slightly with aircraft type, ranging from 0.58 to 0.60 for the assumed value of safety factor of 1.75. Moreover, it appears practically impossible to increase PCASE reliability above 90%, since safety factor values of more than 25 are required. This observation suggests that the PCASE design transfer function is in need of reconsideration. It is deemed imperative that a limit state design concept be implemented in pavement design, to complement current approaches. Such a change will also serve the purpose of enhancing pavement resilience to catastrophic events.