Integrated Structural and Ventilation System for Buildings through Biomimicry

Current estimates suggest that buildings are responsible for about 40 percent of U.S. energy usage.  Nature has potential solutions for energy efficiency by integrating systems.  Specifically, insects such as termites construct habitats that are structurally stable, regulate internal temperature and provide ventilation through the form of the structure.  By computationally mimicking the bottom-up building processes of integrating structural system with ventilation, this study intends to develop a new paradigm for building design.  The resulting forms can provide an avenue for new solutions in construction of habitats that require little to no external energy for ventilation, particularly in developing areas where the cost of energy is prohibitive.

This research looks at structural forms and building systems from a new perspective.  Rather than focusing on traditional top-down design based on generalized and codified environmental inputs, the research aims to consider the integration of the structural system as part of a responsive habitat modeled on biomimicry of nature. Agent-based modeling is a computational approach by which predictions can be made on complex systems controlled by rules of behavior of individual agent. This can be extended to the physical manifestation of agent movement and include constraints to ensure structural stability.  By considering local environmental inputs and adaptable agent based algorithms, a platform will be developed in which structural forms and systems are developed that consider buildings more naturally as an extended physiology of the inhabitants, responding to both local environmental stimuli and intended structural function. This multi-disciplinary effort will build on the current state of the art in engineering, atmospheric science and entomology.  In structures, it will employ biomimicry and agent-based modeling to create new paradigms for bottom-up development of section and member topologies that are integrated with environmental function.  In atmospheric science, feedbacks between built environments and models of local microclimate will be explored. Numerical simulation will contribute to the state of the art in the understanding of natural ventilation. The developed topologies intend to serve as a proof of concept for fully integrated structural / mechanical building systems.


Funding Agency
Agency: National Science Foundation (NSF)
Institute:
Type:
Application # 1436850

Collaborators

  • Andrea Surovek
  • William Capehart
  • Khosro Shahbazi
  • Tyrone Phillips
  • Hannah Moen
  • Clint Leeper
  • Nicholas Claggett

Consultants

  • J. Scott Turner
  • Paul Bardunias
  • Rupert Soar
  • Bret Lingwall

Collaborative Agencies

  • Cheetah Conservation Fund (CCF)
  • Indian Institute of Science

Products

Obtaining inspiration from biological and natural systems, or biomimicry, has been successfully employed in engineering and science to develop both new technology and new paradigms in design.  Integration of systems is a key feature in sustainable design, and termites are experts at integration of large, stable structural forms and the mechanical function necessary to maintain a livable space for both termites and the fungi with which they live symbiotically.  In closed termite mounds, such as those built by Macrotermes michaelseni of central Namibia, traditional concepts of stack effect do not account for the movement of air in the structure or the gas exchange necessary for the termites to survive.  Instead, a series of internal tunnels and within the mounds structure and porosity of the mound surface combine to provide ventilation for the mounds. 

The primary purpose of this project was to examine the relationships between the structural form of the mound, mound material, the internal tunnel structure and influence of climate on the form and function of the mounds to inform sustainable building practices.  The influence of species, climate and materials on the shape class of the mound were determined by developing a database of mounds.  A correlation of mound shapes to material and climate shows that the overall climate of an area has less impact on the shape class of a mound than the locally available materials, in contrast to many hypotheses that suggest climate was the most significant contributor to mound shape.   The database of mounds is available at http://www.termitemounds.org.  the website will also host a suite of three-dimensional models developed using photogrammetry to capture the topology of the mounds.  The models will be available in STL format for use by researchers in developing meshes for FEA or CFD analysis.

Simplified models were developed for more rapid parametric assessment of the mounds.  To build a more realistic model for easier meshing, a generic mound exterior is assumed with vertical interior voids that are parameterized, at a given cross-section height, void ratio (area ratio of void to solid mound) and wall thickness. Two arbitrary parameters where added which include the number of channels and rotation of these channels as a function of height. This model lacks the inherent complexity of naturally-built mounds; however, it significantly eases the CFD modelling of the interior of the mound. In addition, improvements were made in the probabilistic determination of atmospheric influences on the mound behavior including collection of weather data at a field site in Namibia.  SDMines’ THREDDS (Thermal Real-time Environmental Distributed Data Services) servers are currently serve Archived and Real-time Namibia Atmospheric Simulations, and Climate Data.  these datasets are accessible through OPeNDAP protocols and can be directly accessed through the server by other projects and investigators using resources such as R, MATLAB, IDL and ArcGIS.

The research provided significant multidisciplinary training for researchers from structural engineering, mechanical engineering, materials, atmospheric sciences, entomology and biology.  Two faculty, one post-doctoral scholar and two undergraduates obtained international field research experience.  The research provided training for two female undergraduate students; one completed an MS degree in engineering, and the other begins her PhD program on related research in the Fall of 2019.  Two other students funded on the project completed their MS degrees. One post-doctoral researcher had the opportunity to do transdisciplinary research and is currently working in industry. One team from SDSMT competed in the national Biomimicry Challenge, and local elementary students were taught about biomimicry, or ?learning from nature? and differences in basic soil types.  A Minecraft model of the termite mound was developed to show students what it would be like to be a termite winding through the tunnels of the mound and showed just how large a mound would be if termites were people-sized. The research has been shared through conference presentations, poster sessions, invited talks and development of a new Technical Committee on Bioinspired Structures for the American Society of Civil Engineers.


Publications

Claggett, A. Surovek, W. Capehart and K. Shahbazi “Termite Mounds: A Bioinspired examination of the role of material and environment in the development of multi-functional structural forms.”JOURNAL OF STRUCTURAL ENGINEERING, v.144, 2018, p..doi:0733-9445

Claggett, A. Surovek, B. Streeter, S. Nam, P. Bardunias, B. Cetin “Biomimicry and locally responsive construction: Lessons from termite mounds for structural sustainability” INSIGHTS AND INNOVATIONS IN STRUCTURAL ENGINEERING, MECHANICS AND COMPUTATION: PROCEEDINGS OF THE SIXTH INTERNATIONAL CONFERENCE ON STRUCTURAL ENGINEERING, MECHANICS AND COMPUTATION, CAPE TOWN, SOUTH AFRICA, 5-7 SEPTEMBER 2016, v., 2016, p.. doi:9781138029279

Claggett, Nicholas and Surovek, Andrea and Capehart, William and Shahbazi, Khosro “Termite Mounds: Bioinspired Examination of the Role of Material and Environment in Multifunctional Structural Forms” JOURNAL OF STRUCTURAL ENGINEERING, v.144,  2018, p.. doi:10.1061/(ASCE)ST.1943-541X.0002043  

Surovek, P. Bardunias, T. Phillips, w. Capehart & K. Shahbazi “Biomimicry of Natural Habitats: Integration of Structural Topology and Mechanical Function” 6TH STRUCTURAL ENGINEERS WORLD CONGRESS, v., 2017, p..

Claggett, A. Surovek, B. Streeter, S. Nam, P. Bardunias and B. Cetin “Biomimicry and locally responsive construction: Lessons from termite mounds for structural sustainability” INSIGHTS AND INNOVATIONS IN STRUCTURAL ENGINEERING, MECHANICS AND COMPUTATION, v., 2016, p.293.  doi:9781138029279