Property Risk Assessment for Expansive Soils in Louisiana

Abstract

The physical properties of soil can affect the stability of construction. In particular, soil swelling potential (a term which includes swelling/shrinking) is often overlooked as a natural hazard. Similar to risk assessment for other hazards, assessing risk for soil swelling can be defined as the product of the probability of the hazard and the value of property subjected to the hazard. This research utilizes past engineering and geological assessments of soil swelling potential, along with economic data from the U.S. Census, to assess the risk for soil swelling at the census-block level in Louisiana, a U.S. state with a relatively dense population that is vulnerable to expansive soils. Results suggest that the coastal parts of the state face the highest risk, particularly in the areas of greater population concentrations, but that all developed parts of the state have some risk. The annual historical property loss, per capita property loss, and per building property loss are all concentrated in southeastern Louisiana and extreme southwestern Louisiana, but the concentration of wealth in cities increases the historical property loss in most of the urban areas. Projections of loss by 2050 show a similar pattern, but with increased per building loss in and around a swath of cities across southwestern and south-central Louisiana. These results may assist engineers, architects, and developers as they strive to enhance the resilience of buildings and infrastructure to the multitude of environmental hazards in Louisiana.

Future Property Risk Estimation For Wildfire In Louisiana, USA

“…The method of projecting population (𝑃) at the census-block (i) scale by the year 2050 follows that of Mostafiz et al (2020a;2020b;2021a;2021b). Because annual census-block level population estimates are unavailable, the process begins with parish-(i.e., county-) wide annual growth rate calculations.…”

“…The abrupt, sizeable, and temporary population redistributions both within and beyond Louisiana in the wake of significant hurricanes (most notably Katrina in 2005) are likely contributors to the low explained variance. The procedure selected is least sensitive to these concerns and was also implemented effectively in Mostafiz et al (2020a;2021a;2021b).…”

“…To evaluate current and future structure value (𝑆𝑉) in each census block, the total number of buildings in each census block in 2010 (𝑁 2010,𝑖 ) is acquired from the U.S. Census Bureau (2010) by summing the buildings constructed during each time interval as reported in the shapefiles (Mostafiz et al 2021a). Then this value is multiplied by the mean building value in 2010 in a given census block (𝑀𝑉 2010,𝑖 ) to give the total 𝑆𝑉 in that census block (𝑆𝑉 2010,𝑖 ), as shown in Equation 3:…”

Unveiling the Hidden Threat: Drought‐Induced Inelastic Subsidence in Expansive Soils

“…Elastic deformation often retains large amplitudes and has immediate impacts on structures and infrastructure. There are significant studies about the elastic deformation of expansive soils under varying moisture conditions in geotechnical engineering, often referred as seasonal subsidence and heave (e.g., Barthélémy et al., 2023; Charpentier et al., 2022; Kai et al., 2020; Mostafiz et al., 2021; Wang, 2022a). These studies have been pivotal in understanding soil behavior under drought conditions and their corresponding damage to buildings and infrastructures.…”

A new drought index fitted to clay shrinkage induced subsidence over France: benefits of interactive leaf area index

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Clay shrinkage, which consists of a reduction in the volume of clay soils during dry periods, can affect buildings and cause subsidence damage. In France, losses due to subsidence are estimated at more than 16 billion € for the period 1989-2021 (CCR, 2021, and are expected to increase under the effect of climate warming. This work aims to improve the current understanding of the conditions triggering subsidence by proposing an innovative drought index.

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