Hamid Kaboli

PhD Candidate, Sustainable Building Systems

hkaboli@umass.edu

Hamid Kaboli is a PhD candidate in the Environmental Conservation degree program (Building Systems concentration) at UMass Amherst. Hamid conducted his undergraduate study as a civil engineer at the University of Tehran and continued his education as a graduate student in the Architectural technology program, University of Tehran to an MS Degree concentrating on space structures and structural glass systems. With a background of both engineering and architecture, he is continuing his research in an interdisciplinary area of study focused on engineered wood products, such as reinforced LVB (Laminated Veneer Bamboo) beams and more.

Project: Low-Value Northeastern Wood in Cross Laminated Timber

Dissertation Committee:
Chair: P.L. Clouston
Members: S.R. Arwade & A.C. Schreyer

Project Description:
Known in the building industry throughout the world, Cross Laminated Timber (CLT) is a massive timber building material with outstanding structural, fire, and seismic properties. CLT is a cost-competitive, sustainable construction material is a good candidate as a substitute material for concrete, masonry, and steel, in mid-rise and high-rise buildings. CLT is perpendicular layers of dimensional lumbers usually laminated together and forming a massive structural panel. This study explores the viability of utilizing Massachusetts grown Eastern Hemlock and Eastern White Pine in CLT panels as pure or in conjunction with other high-value wood products. 59% of Massachusetts’ lands are covered with timberlands and in absence of a sustainable market, only 20% of the state’s capacity is harvested each year. Harvesting infested species such as Eastern Hemlock needs an available market for low-quality timbers to justify thinning costs. CLT can provide a sustainable market for local species with an opportunity to incorporate underutilized species in middle layers.

This prospectus discusses in-house fabrication of bending and shear specimens of hybrid CLT panels made out of Northeastern local spices in pure or in conjunction with higher quality lumbers. Analytical and experimental studies are applied to evaluate structural performance of hybrid CLTs and the results are compared with ANSI/APA-PRG 320 to meet the minimum structural requirements for standard grades. The preliminary study included bending tests on 4 Eastern Hemlock hybrid CLT panels which revealed acceptable bending strength and stiffness of hybrid CLT panels using Machine Stress Rated (MSR) boards in the bottom layer. Further short-span and rolling shear tests are proposed for a better understanding of hybrid panels shear properties. The same series of experimental tests are also proposed to evaluate structural performance of Eastern White Pine hybrid CLT panels.