Load-bearing capacity of wood polyvinyl chloride composite log-walls with openings strengthened with steel flat bars via experimental and numerical studies

In this research, the load bearing behavior of strengthened hollow WPVC composite log-wall panels using steel flat bars (SFBs) was examined experimentally and verified numerically with a finite element model (FE-model). The validated FE-model was extended to study the load carrying behavior of full-scale log-wall panels. The results indicated that the new log element cross-section gave an average maximum load-bearing capacity of 40.3 kN/m at an average maximum displacement of 12.07 mm and prevented side sway and fracture near the connection between the web and the flange. For the strengthened middle part between the openings of the log wall panel, SFBs and an extra flange member provided an average maximum load-bearing capacity of 48 kN/m at an average maximum displacement of 20.4 mm, and helped to control the deformation shape, prevented the separation of log layers, and provided the panel with low ductility. Good bonding between the contact surfaces of the WPVC composite and the SFBs was achieved. In a comparison between the experiment and the FE-model simulation, similar trends in the load-displacement relationship, strain intensity, and deformed shape were obtained, which confirmed the accuracy of the FE-model used. The numerical results for full-scale log-wall panels using the validated FE-model also showed that WPVC composite panels with two openings can carry loads of 4.12 and 4.69 kN/m, which satisfies the requirements for a load-bearing wall in a one-story house with a roof span of up to 4 m and a total load of less than 3.28 kN/m, excluding the lateral load.