Tracing Crack Propagation of Concrete Acted by Transient Temperature Field

A model was set up using element-free method (EFM) to trace crack propagation of concrete acted by transient temperature field. The time-varying rules of temperature, stress and stress intensity factor at concrete crack tip were analyzed to get the time of crack initiation and the whole process of crack propagation. In addition the effects of the change rate of external temperature and crack depth on crack propagation were discussed. The results show that surface crack can possibly develop into penetrative crack acted by variable external temperature, which would wreck structural stability, and surface crack propagation is more likely to initiate in shorter period when the change rate of external temperature is higher. What's more, the deeper crack is, and the easier and the rapider crack initiation are.