Treesearch

The collective U.S. housing market, on a monthly basis, was mixed in April 2018. Encouraging were the year-over-year readings, which were overwhelmingly positive, except for existing house sales. Single-family housing starts, permits, and under construction improved on a monthly basis. Existing house sales were negative on a month-over-month and year-over-year basis. Regionally, data were mixed across all sectors.

The collective U.S. housing market was mixed in February, and once again new single-family (SF) sales were revised sharply downward. SF housing starts were robust, and other housing categories appear to have flat-lined on a monthly basis. Regionally, data were mixed across all sectors. New SF construction and remodeling spending remain positive, increasing at an incremental pace.

The collective U.S. housing market was mixed in March, and new single-family (SF) sales improved positively on a monthly basis. SF housing starts declined on a monthly basis, as well as new SF construction and remodeling spending. Existing house sales were negative on a year-over-year basis. Other housing categories appear to have flat-lined on a monthly basis. Regionally, data were mixed across all sectors.

In the fourth quarter the U.S. housing markets improved incrementally from quarter three. Total permits, single-family starts, new house sales, and single-family spending all improved modestly quarter-over-quarter. The majority of sectors increased on a year-over-year basis as well; only multifamily starts decreased, albeit minimally. Viewed from a recent historical context, all housing construction subsectors exceeded the record lows recorded in the 2008 to 2011 time period.

Cellulose nanocrystals (CNCs) are routinely produced as aqueous suspensions. These are then typically freeze-dried in order to be added into polymeric composites using melt-blending. However, dispersing freeze-dried CNCs into hydrophobic polymers is a challenge. In this study, our objective was to advance our understanding of the impact of freeze-drying methods on the morphology of dried cellulose nanocrystals (CNCs), and on the tensile properties of the resulting PLA-CNC nanocomposites. CNCs were prepared as aqueous suspensions with 10.7% solids content using a sulfuric acid method, and...

The objectives of this study were to investigate the wear behavior of drill bits in wood drilling resistance measurements and to understand how the blunting of the cutting edges may affect the cutting forces and ultimately the measurement results. Laboratory resistance drilling experiments were conducted using an IML-RESI PD 400 tool (IML Instrumenta Mechanik Labor GmbH, Wiesloch, Germany) and a standard spade-type drill bit. Results were based on 375 drillings made on a 2.58 m long, freshly cut, defect-free yellow birch (Betula alleghaniensis) log with an average MC of 55.5%, an average...

The objective of this study was to determine the technical feasibility of combining acoustic wave data with high-resolution laser scanning data to improve the accuracy of defect detection and quality assessment in hardwood logs. Using acoustic impact testing and high-resolution laser scanning techniques, 21 yellow poplar logs (Liriodendron tulipifera) obtained from the central Appalachian region were evaluated for internal and external defects. These logs were then sawn into boards and the boards were visually graded based on the National Hardwood Lumber Association grading rules. The...

The objective of this study was to determine the technical feasibility of combining acousticwave data with high-resolution laser scanning data to improve the accuracy of defect detection and quality assessment in hardwood logs. This article (Part 1) focused on exploring the potential of an acoustic impact testing method coupled with advanced waveform analysis to detect internal decay of hardwood logs and classify logs in terms of log quality and potential board grade yields. Twenty-one yellow-poplar (Liriodendron tulipifera)logs obtained from the Central Appalachian region were evaluated...

Durability of wood products intended for use in outdoor aboveground applications are evaluated using one or more standardized test methods. These methods use relatively small specimens in an effort to accelerate decay growth and allow detection of decay. In this study, we evaluated internal moisture content and temperature of standardized specimens and compared them with specimens of a simulated post and beam connection that is recommended for residential deck construction. Specimens of each type were cut from end-matched Southern Pine timbers and exposed above ground at a test site near...

This research focused on evaluating the bending stiffness and strength of structural lumber with transverse vibration nondestructive testing techniques. A random sample of nominal 2-in.- (standard 38-mm-) thick Southern Pine dimension lumber was obtained from several mills in southeastern United States. After conditioning, the lumber specimens were nondestructively tested using transverse vibration techniques. Modulus of elasticity (MOE) was determined using the frequency of oscillation and density. Static bending MOE and strength were then determined for each specimen. Statistical...