Mechanical characterisation of corner joints in short timber support system

This study examined the mechanical characteristics of timber carpentry corner joints within the timber chock structures, commonly used in underground mining as a standing support system to stabilize the deformed roadways. Timber chock structures efficiently transfer converging load through full contact and interlocking of saddle-notched beam elements. A systematic experimental program was conducted to assess the mechanical behaviour of Australian hardwood short timber chocks under compression where their horizontal and vertical deformations were examined extensively. Additionally, digital image correlation (DIC) was employed to precisely measure the displacement and strain distribution, facilitating a comprehensive analysis of the crack initiation and damage propagation within the timber components. Furthermore, the influence of notch corner shapes on the mechanical behaviour of timber structures including double-rounded and double-rectangular corners was investigated. Subsequently, a robust finite element method utilising the continuum damage mechanics approach was employed to evaluate the mechanical performance of short timber chocks at the contact levels. The results indicated that the developed numerical model can effectively model the propagation of damage within the short timber chock structures. The generated experimental and numerical data have offered valuable insights into the performance of timber chocks in underground environments.