Grantee Research Project Results
Final Report: Green Oak as a Sustainable Building Material
EPA Grant Number: SU835729Title: Green Oak as a Sustainable Building Material
Investigators: Shelton, Ted , French, Robert C. , Taylor, Adam M , Bennett, Richard M , Collett, Brad , Retherford, Jennifer , Schwartz, John , Stuth, Tricia
Institution: University of Tennessee
EPA Project Officer: Page, Angela
Phase: II
Project Period: October 1, 2014 through August 14, 2016 (Extended to July 31, 2017)
Project Amount: $90,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet - Phase 2 (2014) Recipients Lists
Research Category: P3 Challenge Area - Sustainable and Healthy Communities , P3 Challenge Area - Air Quality , Sustainable and Healthy Communities
Objective:
The primary objectives in Phase II were:
• To develop, detail, and construct a full-scale building using green oak pallet cants as structural members.
• To monitor, record, and analyze the demonstration project for structural, acoustic, and thermal performance over a two-year period as the green oak members dry.
• To disseminate our findings widely through multiple digital media platforms, peer reviewed publications, design award programs, and programs recognizing the integration of pedagogy and practice
Summary/Accomplishments (Outputs/Outcomes):
In the final year of the grant, students were able to accomplish several key goals of the research. These included:
- Development and evaluation of a variety of enclosure and opening systems for the primary structural system (bent system).
- Development and evaluation of alternative mass timber structural and enclosure systems using the green oak cants.
- Limited exploration of steam bending techniques using strips cut from green cants to create structural and enclosure systems. (No successful results.)
- Exploration of the use of shou sugi ban, a traditional Japanese technique of charring wood, as a method for providing a protective exterior finish for the green oak.
- Additional break testing of cants to compare failure modes between new green members to that of members that have been drying for a year. A key finding of this testing was that the tested members “clearly exhibited inelastic deformation during the loading” making assumed modulus of rupture values inaccurate for the purposes of design. (See report on bridge design at https://greenoakrevisited.wordpress.com/
- Detailed examination of the structural use of green oak pallet cants in ancillary infrastructural projects – particularly bridges. This included the identification and evaluation of precedent projects, adaptation of lessons learned from precedents to green oak technologies, design of a demonstration project, structural engineering of demonstration project, and full size constructed mockup of a section of the demonstration bridge project.
Conclusions:
The Green Oak Project was able to achieve several key goals including: developing a flexible structural system for the construction of residential- and small commercial-scale buildings, constructing a full-size building structural mock-up of the bent system, developing and demonstrating several methods of enclosing the building structure, developing a mass timber building method using the hardwood cants, constructing a full-size bridge section mock-up, performing structural break testing that provided engineering design guidelines for both the building structure and the bridge structure. These results were disseminated in presentations to visiting professionals, a presentation at an academic conference and the associated publication as part of the conference’s proceedings, and through two websites.
The inability of our initial community partner to provide some of the support they had intended eliminated the possibility of in-situ construction, which was a great disappointment. However, the identification of the Children’s Defense Fund as a new community partner has opened the possibility of future in-situ construction of both a vehicular/pedestrian bridge and small residential structures. We remain hopeful that this will come to pass as a direct outcome of the work of the Green Oak Project. Built examples would, of course, be powerful exemplars for using green oak structurally and architecturally and would likely go further toward adoption of this material than any study or report.
An additional difficulty was attracting large enough numbers of students to the project to sustain a serious building effort. Though the students who were involved produced a significant amount of work in relation to their numbers, it is doubtful that an in-situ build effort could have been mounted with the small numbers engaged in any given semester. (See summary of student involvement below.)
Though an in-situ construction would have been the apex of the work, the research nonetheless demonstrated the viability of green oak as a structural and architectural material including the production of engineering design guidelines for the cants, which were derived through break testing. We are confident that this will set the stage for a future in-situ construction as soon as the correct community partner is identified. We hold great hope that, with their national training and meeting facility at Haley Farm in Clinton, Tennessee, the Children’s Defense Fund is that partner.
Journal Articles:
No journal articles submitted with this report: View all 2 publications for this projectSupplemental Keywords:
built environment, forest products, energy efficiency, embodied energy, housing, green design, environmentally benign substitute, conservation, design for the environment, green building, alternative construction material, architectural design
Relevant Websites:
Progress and Final Reports:
Original AbstractP3 Phase I:
Green Oak as a Sustainable Building Material | Final ReportThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.