H. M. Barnes

Bending properties of wood treated with a new organic wood preservative system

This study investigated the effect of treatment of southern pine with a new generation, all organic wood preserving system on the mechanical properties in bending. Static bending tests showed no deleterious effects of treatment on property values when compared with untreated controls. Values for samples treated to 0.774 kg/m(3) total active ingredients (ai) were lower when compared to a lower retention (0.184 kg/m(3)) or to a standard copper azole system, but were not different than water-treated controls.

Effect of copper xyligen treatment on bending properties of wood

No abstract available

Wood: Preservative Treated

Abstract After a brief historical introduction, this article details the current preservative treatments and preservatives in the marketplace today. Particular emphasis is put on novel and new approaches to wood preservation. Wood modification is emphasized as are newer preservative systems and standards. The new Use Category System developed by the American Wood Protection Association (AWPA) is presented. Environmental and energy concerns as driving forces are discussed.

Supplemental Treatments for Timber Bridge Components

A series of joint treatments on southern pine, red oak, and yellow-poplar were evaluated. These included treatments applied in holes that were subsequently capped, treatments applied to bolt holes and/or bolts, treatments applied to felt pads located between wooden members, and treatments applied directly to the surfaces of the joints. Water-soluble diffusible systems applied in holes adjacent to joints generally performed more poorly than expected because of the lack of rainfall during the exposure period. The notable exception was a copper-borate paste applied directly to the joint area. Application of a solvent-borne copper naphthenate with or without a water repellent to felt pads was also very effective. Water repellent alone and fumigant treatments gave unsatisfactory performance over the long term. To simulate hazards encountered by piling, kiln-dried untreated southern pine pole stubs that received various supplemental treatments were placed in the field for 41 months. Upon groundline evaluation of these test specimens, it was noted that seven preservatives or combinations of preservatives looked very favorable. The following treatments yielded sound stubs with no evidence of decay or insect attack: (1) copper-borate paste applied to the surface at and below groundline; (2) copper-borate paste applied to the surface at and below groundline plus boron rods inserted into holes near groundline; (3) copper-borate paste applied to the surface at and below groundline plus fumigant inserted into holes near groundline; (4) pentachlorophenol grease applied to the surface at and below groundline; (5) fluoride paste applied to the surface at and below groundline; (6) fluoride paste applied to the surface at and below groundline plus boron rods inserted into holes near groundline; and (7) fluoride paste applied to the surface at and below groundline plus fumigant inserted into holes near groundline.

Suitability of live and fire-killed small-diameter ponderosa and lodgepole pine trees for manufacturing a new structural wood composite

Finding alternative uses for raw material from small-diameter trees is a critical problem throughout the United States. In western states, a lack of markets for small-diameter ponderosa pine (Pinus ponderosa) and lodgepole pine (Pinus contorta) can contribute to problems associated with overstocking. To test the feasibility of producing structural composite lumber (SCL) beams from these two western species, we used a new technology called steam-pressed scrim lumber (SPSL) based on scrimming technology developed in Australia. Both standing green and fire-killed ponderosa and lodgepole pine logs were used in an initial test. Fire-killed logs of both species were found to be unsuitable for producing SPSL but green logs were suitable for producing SPSL. For SPSL from green material, ponderosa pine had significantly higher modulus of rupture and work-to-maximum load values than did SPSL from lodgepole pine. Modulus of elasticity was higher for lodgepole pine. The presence of blows was greater with lodgepole pine than with ponderosa. Blows had a negative effect on the mechanical properties of ponderosa pine but no significant effect on the mechanical properties of SPSL from lodgepole pine. An evaluation of non-destructive testing methods showed that X-ray could be used to determine low density areas in parent beams. The use of a sonic compression wave tester for NDE evaluation of modulus of rupture showed some promise with SPSL but requires further research.

Comparison of Wood Utility Crossarm Properties from 1995 and 2015

Abstract In response to changes in forest management and conversion practices, concern has arisen that some solid wood products manufactured today exhibit decreased strength and stiffness propertie...