Research on Fracture Analysis of Box Girder with Crack Damage under
Combined Loads
Abstract
Abstract: The paper adopts the stress intensity factor (SIF) to carry
out the fracture analysis of the box girder structure under complex load
cases based on the linear elastic fracture mechanics. The related
factors of crack length, crack angle, and load level are investigated
emphatically. And the side load as additional impact is also
investigated. The effective stress intensity factor (ESIF) and crack
growth angle are obtained to evaluate the fracture performance. The
results show that the effect of bending and torsion loads can be
considered adopting a linear superposition rule. In analysis, the
bending load can mainly promote opening fracture, and the torsion load
can mainly promote sliding and tearing fracture. The change of inclined
crack will cause mutual evolution between the three types of SIFs. But
the torsion load has not very sensitive to the crack angles. The
additional side load has a great effect on the SIFs (mode-I) along the
crack front to make upper surface of deck plate dangerous. It is also
found that the ESIFs are very larger at small crack growth angles. These
conclusions can provide a feasible way to evaluate the fatigue
performance of box girder.