Download or read book Strength and Stiffness of Reinforced Yellow poplar Glued laminated Beams written by and published by . This book was released on 1997 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: In bridge applications, it is often necessary to minimize the depth of the bridge structure to provide for the required hydraulic opening or reduce the volume of approach fill. For bridges that utilize structural glued-laminated (glulam) timber beams as stringers, reinforcement using thin strips of pultruded E-glass-fiber-reinforced plastic (GFRP) composites may permit reduced depth, because the reinforcement has the potential to increase stiffness and strength. This study is part of an overall effort aimed at evaluating the potential for commercial production of glulam-GFRP beams in current wood laminating plants and a wood adhesive compatible with existing equipment. Twelve Yellow-Poplar glulam GFRP beams were commercially manufactured, and their performance was evaluated. The GFRP panels were bonded to the wood with a resorcinol formaldehyde adhesive to provide the reinforcement. The simplicity of the process used to manufacture the test beams indicates that the commercial production of glulam-GFRP beams is feasible. Increases of 18 percent in stiffness and 26 percent in strength were achieved by adding 3 percent of GFRP by volume. The bending strength values of the beams predicted by the ASTM D3737 procedure correlate well with the experimental values. However, the observed delamination of the reinforcement indicates that improved bonding strength of wood--GFRP interfaces is needed. Results of this study will be useful to manufacturers interested in improving the performance of glulam timber beams.

Download or read book Design criteria for large structural glued laminated timber beams using mixed species of visually graded lumber written by Russell Charles Moody and published by . This book was released on 1974 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Efficient Utilization of Red Maple Lumber in Glued laminated Timber Beams written by John J. Janowiak and published by . This book was released on 1995 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Strength Validation and Fire Endurance of Glued laminated Timber Beams written by Erwin L. Schaffer and published by . This book was released on 1986 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: A previous paper presented a reliability-based model to predict the strength of glued-laminated timber beams at both room temperature and during fire exposure. This Monte Carlo simulation procedure generates strength and fire endurance (time-to-failure, TTF) data for glued-laminated beams that allow assessment of mean strength and TTF as well as their variability. This paper reports an effort to validate model predictive capability through an independently fabricated set of 21 glued-laminated beams. Based upon the available data for the model input parameters on lumber strength and stiffness, finger-joint strength, and length of laminating lumber between sequential finger joints, the model of beam strength appears acceptable and possibly slightly conservative. Refinements in the beam strength model allow its use for predicting fire endurance. In this case, the fire endurance is measured by the TTF and is defined as the time the beam will support its design load while subjected to fire. The residual strength of the beam is analytically calculated by removing the char layer, plus a finite thickness of weakened wood, from the beam cross section as fire exposure time increases. Employing the input parameters for values of finger-joint strength and lamination grades of Douglas-fir, the fire endurance TTF was analyzed for a 5.12- by 16.50-inch 11-lamination Douglas Fir-Larch beam (24F-V4) carrying full allowable uniform load (47.7 lb/in.). (Three-sided fire exposure was assumed; however, four-sided exposure can also be accommodated.) A simulated random fabrication and analysis of the TTF under fire exposure for 100 beams was performed. The mean TTF was estimated as 35.2 minutes with a coefficient of variation of 13.7 percent. Lateral torsional buckling was never the cause of failure in any of the simulations. The results compared well (within a 65 pct confidence band) with the observations and predictions for timber beams reported by sources in other countries. A simulation for a single glulam beam test in cooperation with the National Forest Products Association was also conducted which predicted the result exactly.

Download or read book Strength and Stiffness of Small Glued laminated Beams with Different Qualities of Tension Laminations written by Catherine M. Marx and published by . This book was released on 1981 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Flexural Properties of Glued laminated Southern Pine Beams with Laminations Positioned by Visual stiffness Criteria written by Russell Charles Moody and published by . This book was released on 1970 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Large Glued laminated Timber Beams with Two Grades of Tension Laminations written by Billy Bohannan and published by . This book was released on 1969 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Strength and Stiffness of Glued Laminated Timber Beams written by Johannes Moe and published by . This book was released on 1961 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of the Stiffness of a Roof System Made of Glued laminated Beams and Heavy Timber Decking written by Fred Werren and published by . This book was released on 1961 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Variation of mechanical properties in oak boards and its effect on glued laminated timber written by Cristóbal Tapia Camú and published by Cuvillier Verlag. This book was released on 2022-03-23 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: The renewable material wood and hereof derived structural engineered wood products (EWPs) is widely acknowledged as being the major pillar of sustainable building constructions. Due to an increasing availability and high mechanical performance the wood resource hardwoods has been gaining traction for the use in EWPs, typically dominated by softwoods. Wood, being a naturally grown material, exhibits a pronounced variation in its mechanical properties, presenting marked differences not only between species, but also between individual trees and locally throughout the stem of each tree. Glued laminated timber (GLT) reduces this variation by vertical glue-stacking previously finger-jointed boards to form a highly homogenized wooden beam. This configuration reduces considerably the variation of the observed global mechanical properties of GLT with respect to the individual boards. However, the rather complex material composition of GLT prohibits the derivation of an analytical relation between local (e.g. intra board and finger-joints) and global properties, thus numerical approaches need to be applied. This work addresses the need for an improved understanding and modeling approach of the variability of stiffness and strength along and between boards, and the resulting impact on the size-effect of GLT made of oak.

Download or read book Improved Performance of Southern Pine Structural Glued laminated Timber written by Roland Hernandez and published by . This book was released on 1992 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Improved Utilization of Lumber in Glued Laminated Beams written by Russell Charles Moody and published by . This book was released on 1977 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bending Strength of Water soaked Glued Laminated Beams written by Ronald W. Wolfe and published by . This book was released on 1978 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Flexural Behavior of Large Glued laminated Beams written by Billy Bohannan and published by . This book was released on 1966 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Shear Strength of Glued laminated Beams written by Douglas R. Rammer and published by . This book was released on 1994 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reliability Formulation for the Strength and Fire Endurance of Glued laminated Beams written by and published by . This book was released on 1985 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: A model was developed for predicting the statistical distribution of glued-laminated beam strength and stiffness under normal temperature conditions using available long span modulus of elasticity data, end joint tension test data, and tensile strength data for laminating-grade lumber. The beam strength model predictions compared favorably with test data for glued-laminated beam strength data with 8 and 10 laminations; however, the model predicted strength values 30 percent higher for glued-laminated beam strength data with 4 laminations. Fire endurance and structural resistance were evaluated by artificially reducing the cross section. This reduction accounts for char depth as well as for reduced wood strength caused by the elevated temperature. Average time-to-failure predictions using the developed model compared well with those from conventional prediction methods.

Download or read book Bending Strength of Vertically Glued Laminated Beams with One to Five Plies written by Ronald W. Wolfe and published by . This book was released on 1979 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Properties of vertically laminated beams were studied to determine the effects of number and quality of component laminations on structural performance. Deterministic and probabilistic analyses were both used to show how performance varies with number and quality of laminations and with assumed loading parameters. Increase in allowable stress with number of laminations, currently recognized as a constant adjustment for three or more laminations, was significant for two-lamination beams as well. This increase proved to be inversely related to lumber quality. Results will be helpful to organizations publishing engineering design stresses in establishing a more efficient design of vertically laminated beams. (Author).