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Author ORCID Identifier


Open Access Dissertation

Document Type


Degree Name

Doctor of Philosophy (PhD)

Degree Program

Environmental Conservation

Year Degree Awarded


Month Degree Awarded


First Advisor

Peggi L. Clouston

Subject Categories

Architectural Engineering | Civil Engineering | Mechanics of Materials | Other Engineering Science and Materials | Other Environmental Sciences | Structural Engineering | Structural Materials


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 dissertation 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 the 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 the middle layers.

This dissertation included in-house fabrication of bending and shear specimens of 3-layer hybrid CLT panels. Analytical and experimental studies are applied following the guidelines of ANSI/APA-PRG 320, and the minimum requirements of PRG 320 CLT grades were used to evaluate the structural performance of hybrid panels. The experimental study included major direction long-span bending tests and short-span bending tests as instructed in ANSI/APA-PRG 320 and rolling shear tests complying with ASTM D2718. It was found that Eastern Hemlock hybrid CLT panels could meet the minimum requirements for all PRG 320 CLT grades and bending and shear capacities of Eastern White Pine hybrid panels were greater than the grades V1, V3, and E1.