Affordable, sustainable, and resilient tornado shelter design using compressed stabilized earth block construction

Non-engineered earthen construction is critiqued for being fit only for dry climates and performing poorly against extreme loads. The authors, as part of a National Science Foundation funded collaborative research project, are studying the performance of engineered earthen masonry against tornado-level wind pressures. This paper introduces an affordable, sustainable, and resilient construction system for residential units in high-wind regions utilizing compressed stabilized earth blocks (CSEBs). Interdisciplinary (architectural, structural, construction related) design criteria are considered for the determination of the required strength levels both for the entire residential units and dedicated tornado shelters to be tornado-resistant. The structural capacity required for high wind pressures is calculated using available analytical methods and current codes after the interdisciplinary criteria are optimally negotiated. A preliminary experimental program is then carried out to determine the resistance capacity of lime and cement stabilized CSEB construction. Parameters considered in the experimental work include, but are not limited to: soil characteristics, water to binder ratio, volume fraction of the stabilizer, stabilization type (lime and cement) and mortar composition. A preliminary testing program for CSEB prisms with and without a proposed externally applied strengthening method is also conducted. This paper presents the current findings of this on-going study.