Dimensional Stability and Durability of COM-PLY Studs Exposed to Soaking, High Humidity, and Weathering. COM-PLY Report 18

摘要

One report of a series on the possibilities of producing house framing and structural panels with particleboard cores and veneer facings, this paper describes three studies conducted to simulate different types of job - site weathering exposure on COM - PLY studs. One laboratory study simulated wetting at the job site, while another simulated exposure of studs to high humidity during or after installation. A third study involved exposing studs directly to the weather. The COM - PLY studs were made of two types of resin binders in the particleboard core. The effect of the three types of exposure on strength, stiffness, dimensional stability, and distortion were evaluated by comparing these properties before and after exposure. Solid - wood spruce studs were used for comparison. These simulated site - exposure studies show that structural and dimensional properties of phenolic bonded COM - PLY studs remain stable. In fact, exposure of different groups of phenolic - bonded COM - PLY studs to 48 months of weathering, 36 months of high humidity, and 24 - hour water soakings resulted in only minor losses in strength and stiffness. In weathering tests, COM - PLY studs made with particleboard containing area formaldehyde resin binder retain more strength and stiffness than expected. However, the large dimensional increases of the butt end of the area COM - PLY studs would preclude their use for wall framing. Graphs, tabular data, and a photograph are provided. (Author abstract modified).