This paper reports on the theoretical assessment and ultimate load testing of some prestressed concrete deck planks removed from a structure due to alkali aggregate reaction (AAR) cracking. These were the standard precast prestressed concrete deck planks used for many bridges in Australia some 3 decades ago. The units showed considerable cracking due to AAR which could affect the structural integrity of the units. All planks were tested as simply supported units subjected to four-point loading. This arrangement approximates the loading from a dual axle. The test results included load deflection response under repeated loading followed by monotonically increased load to failure. Strains in the steel strands and in the compression zone of the concrete were monitored throughout the testing regime. These investigations not only provided information about ultimate flexural behaviour, but also about serviceability performance. Theoretical analysis based on nonlinear finite elements gave results that closely agreed with results obtained in the loading tests, particularly when measured material properties were used. (a) For the covering entry of this conference, please see ITRD abstract no. E217099.
Abstract