SCEBs - University of Colorado Boulder

The testing methodology proposed in this report is intended to provide a
systematic process of evaluating potential soils, by applying both geotechnical and
structural engineering principles. Given the availability of a suitable soil, following the
suggested guidelines and criteria will ultimately lead to a satisfactory SCEB. This report
and included testing methodologies are intended to form the foundation on which a
robust best practice standard can be developed. The author does not intend to suggest
that all issues concerning earthen building are addressed directly or that the results
achieved from the provided case studies can be directly extended to any soil other than
the specified soils in the study. However, many of the fundamental concepts and
procedures can be applied more broadly. Currently, the technical level of understanding
is limited to the assumption that regardless of the exact soil composition of the mix in
question, if the mix produces a high quality product then it is suitable given proper
testing. The testing matrix proposed herein attempts to further define acceptance criteria
and streamline the process required to initiate a SCEB building project.
Identifying the availability of a suitable soil or soil mix for use in SCEB
production is the first step to starting a successful project. While many options are
possible, the soils of interest in this report are referred to as clayey soils and well-graded
sands. The soils are formally classified as per the United Soil Classification System
(USCS). Documenting the soil classification in relation to its performance in SCEB
production will hopefully lead to better understanding of this relationship. Current
building codes offer no suggestions or guidelines for selecting a suitable soil based on
classification. Identifying the optimal soil mix or recipe based on a selection of different
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