Mode I Critical Stress Intensity Factor of Medium - Density Fiberboard Obtained by Single-Edge - Notched Bending Test

The Mode I critical stress intensity factor (KIc) obtained by single-edge-notched bending (SENB) tests of medium-density fiberboard (MDF) was experimentally analyzed. In the SENB test, the critical load for crack propagation (Pc) was determined from the relationship between load/loading-line displacement and load/crack opening displacement (COD). A double cantilever beam (DCB) test was also conducted and the results were compared with those of SENB tests. The value of Mode I critical stress intensity factor was obtained by introducing an additional crack length, when the crack length ranged from 0.5 to 0.7 times the depth of the specimen. This range coincided well with that used to derive the appropriate KIc value in the single-edge-notched tension (SENT) test, which was conducted using the specimens with a similar confi guration cut from the MDF panel used in this study.