Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Civil and Environmental Engineering

First Advisor

Suzette Burckhard


To fill a gap in the literature, this thesis explored the mechanical properties for alternative roof beams of a historic Native American Hidatsa earth lodge. The research demonstrates that in those alternative beams, when Moisture Content (MC) increases, Modulus of Elasticity (E) decreases and deflection increases. The procedure included obtaining dimensions for alternative beams from scaled sketches created by ethnographers and informants who recorded an actual Hidatsa earth lodge in the early 1800s (confirmed by other sources) although no material properties studies have resulted. After calculating loads, the variations in the E were determined using an equation. Using linear analysis, alternative beams were modelled for seven wood types for comparison. The deflection was calculated based on E at various percentages of moisture in the wood. By comparing seven wood types of alternative round roof beams, results indicated that Douglas Fir-Western Larch was the most desirable, having the lowest deflection, followed by these types in order of performance: green ash, cottonwood, Ponderosa pine, American elm, and silver maple.

Library of Congress Subject Headings

Earth houses -- Design and construction.
Wooden beams -- Mechanical properties.
Earth houses -- North Dakota -- Knife River Indian Villages National Historic Site.


Includes bibliographical references (pages 49-52)



Number of Pages



South Dakota State University



Rights Statement

In Copyright