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Barriers To Use Of Cross-Laminated Timber In Maine, Shane R. O'Neill Dec 2023

Barriers To Use Of Cross-Laminated Timber In Maine, Shane R. O'Neill

Forest Resources Faculty Scholarship

To increase understanding of both the adoption rate and in-state manufacturing of mass timber In Maine, the 131st Legislature and Governor Mills passed LD 881, a resolve directing a study of the barriers facing cross-laminated timber In Maine and provide recommendations to promote their use in construction. This study was developed in response to the resolve. The study engaged 108 unique participants to define available training, education, and experiences across the stakeholders throughout the building lifecycle process in the state.

From this information, the following five recommendations are proposed:

  1. Understand the policies and initiatives of other states to develop …


Near-Field Thermal Radiation In Graphene-Based Systems, Hua Lin May 2022

Near-Field Thermal Radiation In Graphene-Based Systems, Hua Lin

Honors College

Radiative heat transfer between two media separated by a sub-wavelength distance (the dominant wavelength of thermal radiation at room temperature is around 10 m.) is referred to as near-field radiative heat transfer (NFRHT). Graphene was found to have one of the greatest levels of NFRHT [1]. Additionally, NFRHT of graphene can be modulated externally via application of a bias voltage to the material [1][2], thereby altering its Fermi energy level. As such, graphene is an ideal candidate for several applications such as NFRHT for thermal switching, nano-gap thermophotovoltaic waste heat recovery, and thermal rectification. Modulation ratios as large as 77.7274 …


Life Cycle Analysis And Implications Of 3d Printed Bio-Based Homes, A Preliminary Study, Claire Liedtka May 2022

Life Cycle Analysis And Implications Of 3d Printed Bio-Based Homes, A Preliminary Study, Claire Liedtka

Honors College

The purpose of this study is to evaluate the life cycle, embodied energy, and sustainability potential for large scale additive manufacturing of 3D printed homes. Additive manufacturing is the process of selectively depositing materials using a 3D printing process, which optimizes material usage and reduces waste. I performed a preliminary Cradle to Cradle Life Cycle Analysis for constructing 3D printed homes using a bio-based material, poly-lactic acid (PLA) filled with wood flour. For purposes of this study, I consider the Life Cycle Analysis to be the environmental assessment of each stage of a product’s life cycle, from material sourcing, processing, …


Growth Ring Orientation Effects In Transverse Softwood Fracture, Parinaz Belalpour Dastjerdi, Eric N. Landis Oct 2021

Growth Ring Orientation Effects In Transverse Softwood Fracture, Parinaz Belalpour Dastjerdi, Eric N. Landis

Civil Engineering Faculty Scholarship

In this study, the fracture mechanics of eastern spruce were characterized in relation to end-grain orientation. Compact tension-type specimens with small pre-formed cracks were prepared such that grain angle varied relative to the load axis. Specimens were loaded under crack mouth opening displacement (CMOD) control as to maintain stable crack growth. Specimen fracture was characterized using both R-curve and bulk fracture energy approaches. The results showed that under a RT grain orientation, as well as grain deviations up to about 40, cracks will follow a path of least resistance in an earlywood region. As the grain angle exceeds …


Synthesis And Accelerated Testing Of Oxynitride Films For High Temperature Applications, Robert J. Lad, Rosemary Smith Feb 2014

Synthesis And Accelerated Testing Of Oxynitride Films For High Temperature Applications, Robert J. Lad, Rosemary Smith

University of Maine Office of Research Administration: Grant Reports

NON-TECHNICAL DESCRIPTION:
There is a critical need for new protective ceramic coatings that can operate in harsh environments with service temperatures in the 1000-1500oC range. These ceramic coatings must exhibit excellent heat resistance, chemical stability, fracture toughness and wear durability so they can be reliably be used in applications such high performance engines, shrouds, rotors, seals, slides, and bearings. A major problem is that conventional ceramic coatings crack and delaminate during thermal cycling in reactive gases at extreme temperatures. This project focuses on developing and testing Si-Al-O-N and Si-Zr-O-N thin film coatings and tailoring their properties to achieve high performance …


Pfi: Commercialization Of Advanced Composites In Offshore Wind Energy, James Ward, Habib J. Dagher, Robert Lindyberg Jun 2013

Pfi: Commercialization Of Advanced Composites In Offshore Wind Energy, James Ward, Habib J. Dagher, Robert Lindyberg

University of Maine Office of Research Administration: Grant Reports

This Partnerships for Innovation (PFI) project--a Type III (A:C) partnership between the University of Maine (UMaine), an NSF PFI graduated grantee (0125343), and Maine Maritime Academy, an institution new to the PFI Program (defined as one that has never been a PFI grantee) and, in this case, new to NSF as well seeks to enable the acceleration of the development of Maine's deepwater offshore wind energy resource by employing an innovation model that will draw upon knowledge and technology from diverse sources. The proposed research addresses the development of key knowledge, experimentally-validated numerical models for combined aerolastic/hydrodynamic loadings; and an …


Development Of Porous Polymeric Implants For Use In Orthopedic Research And Development Applications, Alexander Caddell Apr 2012

Development Of Porous Polymeric Implants For Use In Orthopedic Research And Development Applications, Alexander Caddell

Honors College

Current orthopedic implants comprised of plastic, ceramic, or metal alloys are susceptible to surface degradation at the implant-implant interface. The resulting microscopic fragments cause tissue irritation that can lead to osteolysis. In addition, existing percutaneous implants, such as pins used to stabilize fractures, are prone to bacterial infections due to the inability of the surrounding soft tissue to adhere to the implant and form a biologic seal. The goal of this Honors Thesis was to develop porous polymeric implants for orthopedic research and development applications that improve upon current designs in an attempt to remedy the issues detailed above. A …


Investing In Maine Research Infrastructure: Sustainable Forest Bioproducts, Michael Eckardt, Stephen Shaler, Hemant P. Pendse, Adriaan R. P. Van Heiningen, Robert G. Wagner Dec 2009

Investing In Maine Research Infrastructure: Sustainable Forest Bioproducts, Michael Eckardt, Stephen Shaler, Hemant P. Pendse, Adriaan R. P. Van Heiningen, Robert G. Wagner

University of Maine Office of Research Administration: Grant Reports

The University of Maine, the University of Southern Maine, several baccalaureate institutions in the state, along with other federal, state and local public, private, and non-profit institutions will collaborate to create the Forest Bioproducts Research Institute (FBRI) at the University of Maine. The vision of the FBRI is to advance understanding about the scientific underpinnings, system behavior, and policy implications for the production of forest-based bioproducts that meet societal needs for materials, chemicals, and fuels in an economically and ecologically sustainable manner.

The research plans Integrate three themes. They are (1) forest sustainability modeling of life cycle assessment, (2) integrated …


Design Of Functionally Graded Materials Using Transient Nonlinear Simulations And Genetic Algorithm Optimization, Senthil Vel Oct 2008

Design Of Functionally Graded Materials Using Transient Nonlinear Simulations And Genetic Algorithm Optimization, Senthil Vel

University of Maine Office of Research Administration: Grant Reports

The objective of this research is to develop a robust methodology for the design of functionally graded materials (FGMs). FGMs are advanced composite materials that are engineered to have a smooth spatial variation of material properties. This is achieved by gradually varying the relative volume fractions and microstructure of the material constituents during fabrication. FGM components typically exhibit smaller stresses and higher factors of safety than discretely bonded monolithic materials. The aim of this research project is to create a unified framework for the simultaneous optimization of structural shape, compositional profile and microstructure of metal/ceramic FGMs that are subjected to …


Career: Framework For Integrating Embedded Sensors In Durability Analysis Of Frp Composites In Civil Infrastructure, Roberto A. Lopez-Anido May 2007

Career: Framework For Integrating Embedded Sensors In Durability Analysis Of Frp Composites In Civil Infrastructure, Roberto A. Lopez-Anido

University of Maine Office of Research Administration: Grant Reports

The CAREER proposal will develop a framework to characterize durability of composites in civil infrastructure by integrating fiber-optic embedded sensors with damage mechanics models and life prediction methods. To tackle this problem, a combined analytical and experimental methodology is proposed, as follows: 1) Integrate embedded sensors in composites fabrication by VARTM and filament winding; 2) Implement strain, temperature, moisture and chemical degradation fiber-optic sensors; 3) Evaluate the embedded sensor system with controlled damage; 4) Develop a damage mechanics model and life-prediction methodology for durability analysis based on interrogating senors; 5) Assess reliability of sensor data and scale to composite structures …


Development And Commercialization Of Advanced Wood-Based Composites In Maine, Habib J. Dagher Jun 2006

Development And Commercialization Of Advanced Wood-Based Composites In Maine, Habib J. Dagher

University of Maine Office of Research Administration: Grant Reports

This award is to the University of Maine to support the activity described below for 36 months. The proposal was submitted in response to the Partnerships for Innovation Program Solicitation (NSF 0179).

Partners
The partners for the award include the University of Maine (Lead Institution), Maine Technology Institute, Eastern Maine Development Corporation, State Department of Economic and Community Development, The Manufacturing Extension Partnership, Maine Department of Transportation, Louisiana Pacific, Dow Chemical, State Farm Insurance, Henderson and Bodwell, The Kenway Corporation, Market Development Alliance of the FRP Composites Industry, APA the Engineered Wood Association, National Institutes of Standards and Technology, USDA …


Reu Site In Advanced Engineered Wood Composites, Eric N. Landis Jul 2004

Reu Site In Advanced Engineered Wood Composites, Eric N. Landis

University of Maine Office of Research Administration: Grant Reports

Below are abstracts for the projects conducted by the 10 NSF supported REU students. Included with each abstract are the project supervisor and associated graduate students. The abstracts were written by the students. Structural Durability of FRP Drains in Bridge Decks Micah Florea, Tulane University Advisor: Roberto Lopez Anido Fiber Reinforced Polymers (FRP) are quickly becoming the material of choice to solve civil engineering challenges in corrosive environments. In the state of Maine, where deicing salts are generously applied to roadways every winter, conventional steel down spouts used to drain concrete bridge decks are quickly corroded and need constant replacing. …


Research On Advanced Technologies For Housing: Optimized Frp-Reinforced Osb Panels For Disaster-Resistant Construction, William S. Davids Aug 2003

Research On Advanced Technologies For Housing: Optimized Frp-Reinforced Osb Panels For Disaster-Resistant Construction, William S. Davids

University of Maine Office of Research Administration: Grant Reports

The satisfactory performance of wood-framed housing in a seismic or wind event requires a sufficiently strong, ductile, and energy-absorbing lateral force-resisting system. This project will focus on the development of optimized synthetic fiber-reinforced OSB panels to improve the disaster resistance of conventional wood-frame construction. The project research will employ response simulation, small-scale connection and durability testing, and full-scale shear wall testing. Various fiber-reinforced polymer (FRP) systems will be investigated for reinforcing the OSB panels. Shear tests of individual nailed connections between FRP-reinforced and plain OSB panels and lumber framing will be conducted to determine monotonic and cyclic fastener load-slip relationships. …


Acquisition Of Advanced Engineered Wood Composites Manufacturing And Science Laboratory, Habib J. Dagher, Stephen Shaler, Barry Goodell, Eric N. Landis, Roberto Lopez-Anido, Douglas J. Gardner May 2003

Acquisition Of Advanced Engineered Wood Composites Manufacturing And Science Laboratory, Habib J. Dagher, Stephen Shaler, Barry Goodell, Eric N. Landis, Roberto Lopez-Anido, Douglas J. Gardner

University of Maine Office of Research Administration: Grant Reports

This action is in response to the Major Research Instrumentation Initiative MRI'98 (NSF-98-16). The purpose is to upgrade a Composite-Reinforced-Wood (CRW) Manufacturing Science Laboratory at the University of Maine. The laboratory is part of a new facility designed to develop the next generation of wood composites for construction.

Recent research has shown that Composite Reinforced Wood (CRW) offers superior properties at reduced costs. As in the development of reinforced and prestressed concrete, basic research is needed to unlock the full potential of a wide variety of CRW structural members, e.g. joists, beams, columns, panel and connections. CRW hybrids are unique …


Research Experiences For Undergraduates: Advanced Engineered Wood Composites, Eric N. Landis, Habib J. Dagher Jan 2001

Research Experiences For Undergraduates: Advanced Engineered Wood Composites, Eric N. Landis, Habib J. Dagher

University of Maine Office of Research Administration: Grant Reports

The aim of this program is interdisciplinary research experience for undergraduate science and engineering students. The focal point is the development of the next generation of engineered wood composites for construction applications. The disciplines involved include structural engineering, mechanics, composite materials, and wood science. The educational paradigm will be one of combining hands-on laboratory work with training in fundamental science and engineering principles. Previous experience with REU sites indicates that many students become interested in graduate research when they are able to see the fruits of their work used in some application. Thus the basis of this REU site is …


Acquisition Of A Multi-User Thin Film Synthesis And Processing Facility, Robert J. Lad, John F. Vetelino, William Unertl, Daniel Dwyer, David Frankel Apr 2000

Acquisition Of A Multi-User Thin Film Synthesis And Processing Facility, Robert J. Lad, John F. Vetelino, William Unertl, Daniel Dwyer, David Frankel

University of Maine Office of Research Administration: Grant Reports

A state-of-the-art advanced materials synthesis and processing facility focusing on the growth and fabrication of ceramic- based thin film materials will be funded with the assistance of the Academic Research Infrastructure Program. The facility will include a multi-technique thin film materials synthesis chamber equipped with a microwave plasma source, effusion cells, electron beam evaporators, magnetron sputter sources, and a Kauffman ion source. Characterization capabilities will include in-situ reflection high energy electron diffraction (RHEED), mass spectrometry for controlling growth processes, X-ray photoelectron spectroscopy (XPS), and a novel Hall probe for in- situ film characterization. Three major areas of research will be …


Dickey-Lincoln School Lakes Project Environmental Impact Statement: Appendix G: Recreation Resources (Revised June 1978), U.S. Army, Corps Of Engineers, New England Division, Northern Maine Regional Planning Commission, Land Use Consultants, Inc. Jan 1978

Dickey-Lincoln School Lakes Project Environmental Impact Statement: Appendix G: Recreation Resources (Revised June 1978), U.S. Army, Corps Of Engineers, New England Division, Northern Maine Regional Planning Commission, Land Use Consultants, Inc.

Dickey-Lincoln School Lakes Project

The purpose of this report is to evaluate and describe the existing recreational use and resources of the project area and the encompassing study area and to project the future use of those resources both with and without the Dickey-Lincoln School Lakes Project. The primary impact area of the proposed project (project area) includes the St. John River watershed upstream of the proposed damsites to the confluence of Nine-mile Brook. The area is bounded by the watershed divide with the Allagash River on the east and the Canadian Border on the west. Major tributaries of the St. John affected by …


Dickey-Lincoln School Lakes Project Transmission Studies Environmental Impact Statement: Appendix I: Visual-Recreation Resources Impact Study, United States Department Of Energy Jan 1978

Dickey-Lincoln School Lakes Project Transmission Studies Environmental Impact Statement: Appendix I: Visual-Recreation Resources Impact Study, United States Department Of Energy

Dickey-Lincoln School Lakes Project

The U.S. Departments of the Interior and Energy have conducted system planning, location, and environmental studies for the transmission facilities required for the Dickey-Lincoln School Hydroelectric Project. These studies of many alternate routes have resulted in identification of a proposed transmission line route, and an environmental impact statement as required by the National Environmental Policy Act of 1969. This report, one of several covering various topical areas, is published as an appendix to that statement.


Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 4a: General Design (Revised), New England Division, United States Corps Of Engineers Jan 1977

Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 4a: General Design (Revised), New England Division, United States Corps Of Engineers

Dickey-Lincoln School Lakes Project

This design memorandum presents for review the revised general plan and data for the Dickey-Lincoln School Lakes project, Maine, U.S.A. and Quebec, Canada to provide the basis for preparation of detailed design memoranda, plans and specifications. This document presents revisions to the basic project plan and related data included in the 1967 General Design Memorandum reflecting current water resource requirements. This memorandum serves as a functional design document and 1s presented 1n Phase II level of detail. However, 1n view of the long period of Inactivity, Phase I features have also been incorporated for continuity of project information.


Terrestrial Ecology Of The Dickey-Lincoln School Lakes Project, Corps Of Engineers, New England Division, Environmental Research & Technology, Inc Jan 1976

Terrestrial Ecology Of The Dickey-Lincoln School Lakes Project, Corps Of Engineers, New England Division, Environmental Research & Technology, Inc

Dickey-Lincoln School Lakes Project

This introduction of the St. John River watershed is situated in a transitional zone between the Boreal Forest Formation and the Eastern Deciduous Forest Formation. Second-growth forests representative of these two ecosystems cover extensive areas of the project site. The boreal forest forms a broad transcontinental belt in northern North America and Eurasia, with southern montane extensions. This northern forest is characterized by evergreen, coniferous trees, predominately spruce-fir The eastern deciduous forest, composed of broad-leaved hardwoods, extends throughout the eastern United States except Florida (Dasmann, 1968; Oosting, 1956).