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Mass plywood panel (MPP) is a veneer-based engineered wood product that recently was introduced in the mass-timber construction industry. Preliminary studies show that MPPs can be a preferred construction material for shear walls, floor diaphragms, and roof assemblies. However, no design guide exists regarding the use of MPPs as structural elements. This is compounded by a lack of engineering properties and parameters needed beyond the generic values provided in the product report. To assess the engineering properties and provide a benchmark dataset, a comprehensive experimental testing program characterized the performance of MPPs in flexure, in-plane shear (parallel to major strength direction), compression, and tension. Additionally, the characteristic values of MPPs were derived based on the test results to provide an initial indication of design values of MPPs. The test results presented in this study provide a fundamental basis for the development of a design guide for MPPs. [ABSTRACT FROM AUTHOR]

Cross-laminated timber (CLT) is an engineered wood product offering several advantages for wood utilization in midrise and tall buildings. However, moisture intrusion poses significant risks since it can affect the durability of CLT structural members and their connections. There has been much research on connection performance to understand their seismic response. However, the impact of moisture on the performance of CLT connectors is less understood. Cyclic tests were conducted on a series of CLT shear wall-to-diaphragm L-bracket (angle bracket) connections after subjecting them to a wetting and redrying cycle. The study includes three exposure durations and four wood species (Douglas fir, Southern yellow pine, Norway spruce, and spruce-pine-fir) to investigate the effect of moisture exposure on the connection performance. The performance was characterized in terms of strength, stiffness, and energy dissipation. In addition, two existing engineering force-displacement models were fitted to the experimental data. Results indicate that the changes due to wetting and redrying cycling were not statistically significant for the load-carrying capacity and stiffness. In contrast, a statistically significant decrease in the total energy dissipation capacity was observed. [ABSTRACT FROM AUTHOR]

Organizations are significantly influenced by the corporate cultures of organizations with which they interact. Both the construction and engineered wood products (EWP) manufacturing industries are generally known for operating in a traditional environment maintaining conservative corporate cultures, which can create friction when they try to interact with a more liberal set of specifiers. This study assesses the cultural disparities and communication barriers between specifiers and EWP manufacturers in the Pacific Northwest of the US. The study follows a semi-structured interview protocol to decipher the cultures of companies and professionals from the two industries. The responses are qualitatively analyzed and consolidated to identify specific patterns of organizational behavior. A number of factors are identified that affect the interaction between specifiers and manufacturers, chief among which is the consistent presence of distributors as key intermediaries in the supply chain. Low profit margins, lack of engineering and design competency, and risk-aversion are challenges faced by the manufacturing sector. Consolidated organizational behavioral knowledge from this study will benefit EWP manufacturers, specifiers and policy makers alike to close the gap in communication and improve the cultural compatibility between these two members of the construction value chain. [ABSTRACT FROM AUTHOR]

As oriented strand board (OSB) increases in use, improving the mechanical properties is of importance. Improved in-plane shear properties will allow for more efficient use as well as open up other opportunities in engineered wood products with high shear stresses. Based on classical laminated plate theory, composite laminates with laminate alignment patterns produce higher in-plane shear modulus and strength compared with typical alignment. Oriented strand board was manufactured 13.3-mm thick with and alignment patterns, and in-plane shear, bending, nail connection, and small-scale shear wall properties compared to commercial OSB. Results showed a 24% increase in shear modulus for the alignment when compared with the alignment using a method similar to a standard in-plane shear test. Results also show 10% reduction in bending modulus of elasticity in the parallel direction. Small-scale shear wall tests were insensitive to changes of in-plane shear properties. Lateral nail connection tests showed no reduction in connection yield load, implying that these panels can be used in similar applications without affecting connection properties. [ABSTRACT FROM AUTHOR]

In the last several decades, there has been significant growth in research and development activities in nanomaterials. Nanotech has been used to improve the quality of several materials, including wood and polymer composites, for their application in various fields. Nanofillers, including metal particles, nano oxides, pyrogenic silica, and carbon black, have been employed as polymer additives. However, the value of natural, low-cost, and plentiful clay materials such as nanoclay becomes more apparent as environmental regulations and consumer awareness become more rigorous. This literature outlines the role of nanoclay on polymer composites, especially in the case of thermosetting resins, including epoxy, polyester, urea-formaldehyde, and phenol-formaldehyde resins. The current article is intended to provide a comprehensive source of recent studies and literature on nanoclay as filler, its classification, polymer modification processes using nanoclay, and comparing the performance of different thermosetting polymers based on their fabrication methods through physical and mechanical properties. [ABSTRACT FROM AUTHOR]