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This study investigates the complexities faced by emergency managers in wildfire-prone areas to uncover pressing issues and potential solutions. Four themes are discerned through three focus group discussions with emergency managers from nine counties across California. First, there is unequal access to resources for both risk assessment and response, with counties that have fewer resources facing significant challenges in effectively managing wildfire risks. Second, effective risk communication depends on the available resources and the unique characteristics of each community. Participants stress the need for improved communication tools to reach vulnerable groups (e.g., seniors, individuals with disabilities, non-English-speaking residents). Third, the complexity and confusion surrounding multi-level collaboration in wildfire management is a recurring theme. Participants note that unclear roles and responsibilities between state and federal agencies hinder response efforts, underscoring the need for better coordination and transparent communication at all levels. Fourth, innovative responses (e.g., creative evacuation strategies, collaborative efforts) are recognized as imperative for managing wildfires and their cascading impacts in resource-constrained areas. The findings highlight that achieving equitable and effective preparation, response, and resilience for vulnerable communities requires a comprehensive understanding of wildfire severity and community susceptibility, coupled with active collaboration among emergency managers, policymakers, and both governmental and non-governmental organizations.

Recent major investments in infrastructure in the United States and globally present a crucial opportunity to embed equity within the heart of resilient infrastructure decision-making. Yet there is a notable absence of frameworks within the engineering and scientific fields for integrating equity into planning, design, and maintenance of infrastructure. Additionally, whole-of-government approaches to infrastructure, including the Justice40 Initiative, mimic elements of process management that support exploitative rather than exploratory innovation. These and other policies risk creating innovation traps that limit analytical and engineering advances necessary to prioritize equity in decision-making, identification and disruption of mechanisms that cause or contribute to inequities, and remediation of historic harms. Here, we propose a three-tiered framework toward equitable and resilient infrastructure through restorative justice, incremental policy innovation, and exploratory research innovation. This framework aims to ensure equitable access and benefits of infrastructure, minimize risk disparities, and embrace restorative justice to repair historical and systemic inequities. We outline incremental policy innovation and exploratory research action items to address and mitigate risk disparities, emphasizing the need for community-engaged research and the development of equity metrics. Among other action items, we recommend a certification system-referred to as Social, Environmental, and Economic Development (SEED)-to train infrastructure engineers and planners and ensure attentiveness to gaps that exist within and dynamically interact across each tier of the proposed framework. Through the framework and proposed actions, we advocate for a transformative vision for equitable infrastructure that emphasizes the interconnectedness of social, environmental, and technical dimensions in infrastructure planning, design, and maintenance.

Full-scale testing of lateral pressures in expansive clay under various saturation conditions is crucial to better understand the behavior of these soils and predict potential damage to structures. However, due to their complexity and cost, only a few full-scale physical testing studies on expansive soils have been reported in the literature. This study aims to provide new insight into the evolution of lateral swelling pressure in expansive soils under infiltration via full-scale physical testing. For this purpose, a heavily instrumented 3-m high masonry wall backfilled with an expansive clay was built and subjected to infiltration. The backfill was compacted in 95% of standard Proctor at a moisture content near optimal to simulate field conditions. The degree of saturation, pore-water pressure, temperature, suction, and lateral and vertical pressures were monitored at different locations during the test. Results showed that the development of lateral pressure is rapid during initial saturation and levels out as the clay approaches saturation levels. This finding highlights the importance of monitoring lateral pressure over time to accurately predict its behavior. The study also found that lateral pressure develops prior to vertical pressure, depending on the area and restraint. The lack of vertical pressure observed during the test is attributed to the continued displacement of the concrete block wall and settlement of the clay with increased area and wet weight of the soil. This finding is important for backfill against basement walls, retaining walls, and foundation units, where the mass of the expansive soil is limited, and effective stress is limited to one dimension. [ABSTRACT FROM AUTHOR]

Soil suction is a crucial parameter that affects the behavior of unsaturated soils. The impact of temperature on suction can lead to significant changes in the hydromechanical response of unsaturated soils. However, current models that describe the temperature dependency of soil suction rely mainly on empirical and semiempirical relationships, which do not fully consider the contribution of soil structure and degree of saturation on enthalpy potential. To address this limitation, we propose a novel general model for temperature-dependent soil suction based on thermodynamic laws. The model accounts for the thermodynamic processes that determine the enthalpy of the soil and uses these processes to develop the mathematical relationships required for the model. Specifically, we expand the Gibbs free energy for both internal chemical exchanges and when dealing with the thermodynamic system as a whole. We then combine the resulting equations to obtain a general model for the soil total suction. The model is validated by comparing its predictions against laboratory-measured suction at different temperatures for different soils reported in the literature. Furthermore, we demonstrate the model's potential by showing an application in simulating the soil-water retention curve at different temperatures. The proposed model can contribute to a better understanding of the behavior of unsaturated soils under varying temperature conditions by providing a comprehensive and physics-based approach to modeling temperature-dependent soil suction. [ABSTRACT FROM AUTHOR]

Globally, land subsidence (LS) often adversely impacts infrastructure, humans, and the environment. As climate change intensifies the terrestrial hydrologic cycle and severity of climate extremes, the interplay among extremes (e.g., floods, droughts, wildfires, etc.), LS, and their effects must be better understood since LS can alter the impacts of extreme events, and extreme events can drive LS. Furthermore, several processes causing subsidence (e.g., ice‐rich permafrost degradation, oxidation of organic matter) have been shown to also release greenhouse gases, accelerating climate change. Our review aims to synthesize these complex relationships, including human activities contributing to LS, and to identify the causes and rates of subsidence across diverse landscapes. We primarily focus on the era of synthetic aperture radar (SAR), which has significantly contributed to advancements in our understanding of ground deformations around the world. Ultimately, we identify gaps and opportunities to aid LS monitoring, mitigation, and adaptation strategies and guide interdisciplinary efforts to further our process‐based understanding of subsidence and associated climate feedbacks. We highlight the need to incorporate the interplay of extreme events, LS, and human activities into models, risk and vulnerability assessments, and management practices to develop improved mitigation and adaptation strategies as the global climate warms. Without consideration of such interplay and/or feedback loops, we may underestimate the enhancement of climate change and acceleration of LS across many regions, leaving communities unprepared for their ramifications. Proactive and interdisciplinary efforts should be leveraged to develop strategies and policies that mitigate or reverse anthropogenic LS and climate change impacts. Plain Language Summary: Our article reviews existing research on the global issue of land subsidence (LS), or the relative sinking of the land surface. At the global scale, a variety of LS drivers and physical processes are present and interact with one another. The combination of climatic extremes (e.g., droughts, floods, wildfires, etc.) and LS can lead to devastating impacts on natural and built systems as well as feedbacks within our Earth system that enhance climate change. Yet, a review of the combined effects of extreme events, climate, subsidence, and their impacts, does not currently exist. In this article, we identify and characterize LS drivers, rates, and impacts throughout many different climates (e.g., arid and humid regions) and landscapes (coastal and inland locales, urban and agricultural areas). We also bring together the interplay among extreme events and LS and their connections to climate, human activities, and infrastructure. Integrating such relationships into LS analysis and monitoring frameworks is necessary to better understand cascading hazards and identify vulnerable populations, assess at‐risk infrastructure, and develop mitigation and adaptation strategies for LS. Key Points: Human activities led to the largest land subsidence (LS) rates and greater human exposure to anthropogenic LS is expected in the futureModeling the interplay of extreme events and LS is vital as feedbacks can amplify impacts on infrastructure, the environment, and societyProcesses such as permafrost thaw and soil organic matter oxidation drive LS and release greenhouse gases, enhancing climate change [ABSTRACT FROM AUTHOR]

Civil engineering and construction (CEC) are among primary higher education programs preparing the next generation of subject experts and decision makers working on different aspects of infrastructure resilience, which is a key component of community resilience. However, in the curriculum of most CEC programs, there is no well-established approach for the formal education of students about resilience. Additionally, the evolving nature of the subject makes it even more challenging to develop a comprehensive knowledge foundation for CEC students regarding infrastructure and community resilience. In this situation, the perception of students becomes a critical factor shaping a program, dealing with resilience in the future. The main objective of this study is to examine the perception of CEC students toward community resilience with a primary focus on infrastructure. A quantitative research method was employed to identify challenges, potentials, importance, and gaps in students' knowledge and quantify the comparisons. A survey was designed based on the DeVellis model and completed by 382 students enrolled in CEC programs in 15 universities across the US to assess how students perceive basic terms and factors related to resilience. Both descriptive and inferential methods were used to analyze the data. The results highlight a gap in students' perceptions in terms of resilience definition, factors, scope, and tools, and the potential for better training programs and more engagement is warranted. The findings of this study can be utilized to design, develop, and implement modules to better educate CEC students about the subject matter. Improving the resilience knowledge level among CEC students will equip the next generation of subject experts and decision makers with proper knowledge and tools to enhance preparedness and planning, along with proactive response and recovery before, during, and after adverse natural events. This study contributes to the body of knowledge by providing an assessment on a sample group in the area of resilience within civil engineering curricula and emphasizing the necessity of embracing educational components by corresponding educators and administrators.

Desiccation cracking can significantly affect the hydro-mechanical behaviour of soil in various engineering applications. Characterising the evolution of desiccation-induced shrinkage strain in soils is a key step in understanding the cracking mechanism. This study presents a novel framework for monitoring and early detecting soil cracking by utilising the distributed fibre optical sensing (DFOS) technique based on optical frequency domain reflectometry (OFDR). DFOS-OFDR was integrated into a set of experimental testing to simultaneously monitor water content, crack pattern and strain state. OFDR with 1 με strain measurement accuracy was employed to monitor the initiation and propagation of cracks. The results reveal a strong correlation between the spatiotemporal evolution of soil strain and crack, confirming the efficacy and reliability of the proposed framework. During the drying process, the compressive strain induced by soil shrinkage increases first and starts to decrease when cracking is initiated. Further, DFOS-OFDR demonstrated promising results to predict the position of cracks. Compared to traditional strain monitoring methods with discrete measurements, DFOS-OFDR offers a non-destructive, accurate yet efficient, high-resolution and continuous technique for monitoring and early detection of soil desiccation cracking. [ABSTRACT FROM AUTHOR]

Climatic wetting‐drying cycles exacerbated by climate change can trigger several weakening mechanisms in surface soils, potentially leading to instability and failure of slopes and earthen structures. This study proposes a bio‐mediated approach based on microbially induced calcite precipitation (MICP) to increase soil resilience to wetting‐drying cycles. To explore its viability and the underlying mechanisms, we conducted a series of laboratory tests on clayey soil that underwent six wetting‐drying cycles. The tests were conducted with different treatment methods to investigate the effect of treatment sequence and cementation solution concentration. After MICP treatment, the initial evaporation rate, surface crack ratio during drying, and total soil weight loss during rainfall erosion were reduced by up to 32%, 85%, and 90%, respectively. Spraying the cementation solution first in the MICP treatment sequence proves more effective in improving soil water retention capacity. On the other hand, initiating the sequence with the bacterial solution demonstrates a more pronounced effect in reducing soil desiccation cracks and erosion. Microstructure analysis reveals that the content and distribution of CaCO3 precipitation are the major factors controlling the effectiveness of MICP for the cementation of clayey soil. Employing MICP can minimize the carbon footprint and contribute to developing environmentally friendly solutions for soil improvement in regions affected by climatic wetting‐drying cycles. Plain Language Summary: The rising frequency and intensity of climatic wetting‐drying cycles driven by climate change pose a threat to surface soil stability, consequently increasing the risk of land degradation, soil erosion, landslide, and other forms of ground instabilities and failures. This study presents a bio‐mediated approach using microbially induced calcite precipitation to enhance soil resilience to wetting‐drying cycles. Experimental results show that MICP is capable of improving soil properties related to water retention, desiccation resistance, and erosion control. The microstructure analysis further elucidates the role of MICP‐induced CaCO3 precipitation in cementing clayey soil and demonstrates that the bio‐created buffer barrier significantly mitigates the adverse effect of climatic wetting‐drying cycles on surface soil. This study is expected to offer an environmentally friendly and sustainable soil improvement solution in regions impacted by cascading climatic extremes. Key Points: A sustainable bio‐mediated approach using microbially induced calcite precipitation (MICP) was applied to enhance soil resilience to climatic wetting‐drying cyclesMICP significantly improves water retention, desiccation and erosion resistance of surface soilThis study provides new insights into the fundamental mechanisms of the interaction between climate and MICP‐treated soil [ABSTRACT FROM AUTHOR]