Prestress evaluation in prestressed concrete plate-like structures

摘要

Condition assessment and capacity evaluation of existing structures using their vibration responses have been subjected to extensive research for many years. Prestressed concrete structures have been one of the main focuses of those studies. In the case of prestressed concrete structures, effective prestress force is the most important parameter for their best performance and yet currently there is no effective method for identifying the prestressing force in an existing prestressed concrete structure. Effect of prestressing is different for different types of structural elements and has to be treated accordingly for its accurate quantification. This paper presents a new approach to evaluate the effective prestress force of plate-like structures with simply supported boundary conditions using their vibration responses. The proposed method quantifies the prestress effect with a reasonable good accuracy, even with noisy measurements using both periodic and impulsive excitations. Prestress estimation can be done using collected data from as less as two measurement locations.