Abstract

Simply substituting wood for conventional building materials could provide almost a tenth of the global carbon emission reductions needed to meet 2030 goals. However, while structural light-frame wood products are the go-to building material in the United States for low-rise residential construction, capturing over 90 percent of the market, any kind of wood-frame construction at the time under examination was limited to 5 stories and 85 feet in height. These story and height limitations dated back decades and prevented the design and construction of larger and taller buildings.

In 2014, the American Wood Council (AWC) began developing a plan to expand these limits, but recognized it would require the International Building Code, the predominant model code adopted in most local and state jurisdictions in the United States, to embrace a new type of construction: fire-resistance-rated tall mass timber.

Abstract

Commercial medium-density fiberboard (MDF) products, specifically manufactured for water resistance, were evaluated over 8 days under three water exposure regimes: 90 percent relative humidity, one-sided water spray, and one-sided wet pad. A three-cycle wet-pad and drying exposure test was also performed. Rate of swelling, extent of swelling, and irreversible thickness swelling were determined. Acetylated MDF (AMDF) had the best overall performance, followed by steam-injection pressed MDF (SMDF) and polymeric methylene-diphenyl-diisocyanate–bonded moisture-resistant MDF. The fastest rate of thickness swell and linear expansion occurred with exposure to one-sided water spray and the slowest with 90 percent relative humidity exposure. While AMDF was clearly superior after 24-hour exposure, the other MDF products were nearly identical. Significant difference in thickness swell and water absorption between moisture-resistant MDF and SMDF developed after 24 hours. Regardless of the method of water exposure, the trend of best to worst MDF performance was the same.

Abstract

Mass ply panels (MPP), a relatively new mass timber product, has been utilized in several construction projects as diaphragm and wall panels. Connection for MPP is a crucial structural component that requires a better understanding. This article presents an experimental investigation into elevated temperature exposure–driven property degradation of MPP nailed connections, which is important for both the design of new structures in terms of fire resistance and the rehabilitation of structures partially damaged by fire. One control group and 32 exposure groups, which were combinations of eight elevated temperatures and four exposure durations, were investigated. The failure modes and yield strength of the nailed connection were analyzed as a function of elevated temperature and exposure time and compared with the prediction from the National Design Specification and existing literature. The results show a decrease of up to 45 percent in initial stiffness and ultimate load; meanwhile, there was no statistical evidence for the change in yield load in the majority of testing groups. Two analytical models, namely, multilinear regression and first-order kinetics model, were proposed to model the degradation of initial stiffness and ultimate strength. The kinetics model provided a better prediction and suggested that the initial stiffness and ultimate strength of the nail connection degraded over time at rates depending on the exposure temperature.

By the Forest Products Society Investment Management Committee (IMC)
Justin Price- FPS President
Terry Liles- FPS Former President
Bob Breyer- FPS President Elect
Matt Holt- FPS Vice President
Chris Butts- FPS Executive Vice President
Henry Quesada- SWST President
Victoria Herian, SWST Executive Director

Executive Summary

In accordance with Peter Koch’s letter of Intent a joint FPS and SWST Committee was formed to oversee the management of the Peter and Doris Koch Endowment Funds in 2017. Peter Koch indicated that the purpose of the Oversight Committee is “to audit the previous year’s actions regarding the three endowment funds” and “rule annually

Research and Testing Lead to Historic Code Change

Abstract

Comparison of Water Resistance for Modified Medium-Density Fiberboard

Abstract

Investigation of Thermal Effects on Nailed Connection of Mass Ply Panels

Abstract

A Summary of COVID-19 Pandemic Assistance to US Forest Products Companies

Abstract

Study on the Kansei Image of Linear Elements of Wooden Screens on the Basis of Modern Aesthetics

Abstract

What Drives the Change in Employment in the US Logging Industry? A Directed Acyclic Graph Approach

Abstract

Challenges Facing the Development and Market Introduction of Hardwood Cross-Laminated Timbers

Abstract

Report on the Peter and Doris Koch Endowment Funds through 2021

Executive Summary

Regional Drivers of Primary Wood Processing Mills in the Western Southeast US

Shear and Bending Properties of Homogeneous and Hybrid CLT Panels Fabricated from Low-Value North American Hardwood Species

Impact of Market Price Fluctuations on the Break-Even Log in Hardwood Sawmills

Tourists’ Pro-Environmental Behavior in Forest-Based Tourism through Multi-Methods Analysis

Effect of Decoration Complexity and Age on Aesthetic Evaluation, Purchase Intention, and Visual Attention in Wood Furniture

Moisture Content, Specific Gravity, and Percent Foliage Weight of Cottonwood Biomass

Using Life-Cycle Assessments to Demonstrate the Impact of Using Wood Waste as a Renewable Fuel in Urban Settings for District Heating

Decay Hazard (Scheffer) Index Values in Korea for Exterior Aboveground Wood

Effect of Setting during Construction on Properties of Douglas-Fir Plywood and Oriented Strandboard Flooring

Study on Urea-Formaldehyde Prepolymer and Hot-Press Treatment of Italian Poplar Wood