The frequent occurrence of earthquakes worldwide has rendered highway slope protection projects highly vulnerable to damage from seismic events and their secondary disasters. This severely hampers the smooth implementation of post-disaster rescue and recovery efforts. To address this challenge, this study proposes a comprehensive method for assessing seismic losses in slope protection projects, incorporating factors such as topography and elevation to enhance its universality. The method categorizes seismic losses into two main components: damage to protection structures and costs associated with landslide and rockfall clearance and transportation. This study estimates the cost range for common protection structures and clearance methods under general conditions based on widely recognized quota data in China. It establishes criteria for classifying the damage states of protection structures and provides loss ratio values based on real-world seismic examples and expert experience, constructing a model for assessing damage losses. Additionally, by summarizing the geometric characteristics of soil and rock accumulations on road surfaces, a method for estimating landslide volumes is proposed, considering the dynamic impact of slope gradients on clearance and transportation volumes, and a corresponding cost assessment model for clearance and transportation is developed. The feasibility and reliability of the proposed method are verified through two case studies. The results demonstrate that the method is easy to implement and provides a scientific basis for improving relevant standards and practices. It also offers an efficient and scientific tool for loss assessment to industry practitioners.
Seismic risk assessment of code-noncompliant reinforced concrete (RC) frames faces significant challenges due to structural heterogeneity and the complex interplay of site-specific hazard conditions. This study aims to introduce a novel framework that integrates three key concepts specifically targeting these challenges. Central to the methodology are fragility fuses, which employ a triplet of curves-lower bound, median, and upper bound-to rigorously quantify within-class variability in seismic performance, offering a more nuanced representation of code-noncompliant building behavior compared to conventional single-curve approaches. Complementing this, spectrum-consistent transformations dynamically adjust fragility curves to account for regional spectral shapes and soil categories, ensuring site-specific accuracy by reconciling hazard intensity with local geotechnical conditions. Further enhancing precision, the framework adopts a nonlinear hazard model that captures the curvature of hazard curves in log-log space, overcoming the oversimplifications of linear approximations and significantly improving risk estimates for rare, high-intensity events. Applied to four RC frame typologies (2-5 stories) with diverse geometries and material properties, the framework demonstrates a 15-40 % reduction in risk estimation errors through nonlinear hazard modeling, while spectrum-consistent adjustments show up to 30 % variability in exceedance probabilities across soil classes. Fragility fuses further highlight the impact of structural heterogeneity, with older, non-ductile frames exhibiting 25 % wider confidence intervals in performance. Finally, risk maps are presented for the four frame typologies, making use of non-linear hazard curves and spectrumconsistent fragility fuses accounting for both local effects and within-typology variability.
Rapid urbanization and industrial growth in China have increased brownfield site reclamation, the sustainable remediation for urban transformation and enhancing ecosystem services. However, traditional brownfield safety assessment strategies impose unnecessary costs since excessive remediation. Herein, a comprehensive system integrated by soil self-purification, potential ecological risks and human health risks is developed to investigate the safety of brownfield sites. Indices, including soil environmental loading capacity (SELC), and Nemerow integrated pollution index (NIPI), were introduced to assess heavy metals (HMs) pollution. Results show that 72.05% of the sites are identified as moderate pollution, where Cd, As, and Cr(VI) are at heavy pollution, incorporating soil self-purification. The average values of potential ecological risk (PERI) reached 6615.00, posing a significant damage to the local ecosystem, and Cd was identified as main ecological hazards in the study sites. Furthermore, the health risk assessment shows that children's health risks are higher than that of adults, with non-carcinogenic risk to children (2.60) and adults (0.41), and carcinogenic risk to children (2.30 x 10-3) and adults (1.12 x 10-4). Utilizing a multi-index decision-making approach, it is determined that 19.30% of the site exhibit high-risk values, between concentration screening (11.40%) and risk screening (83.30%) base on single-indices. The study sheds light on the comprehensive assessment of brownfield site safety.
This study examines the key drivers behind the continued reliance on traditional biomass fuels such as charcoal and firewood in urban areas of developing countries, including the city of Lubumbashi. The paper focuses on economic constraints, health problems associated with the use of these fuels, the environmental consequences of growing use and also looks at the alternatives for cooking and their accessibility. The various reasons behind the growing and constant use of charcoal and firewood are examined in the context of the city of Lubumbashi and other developing countries. However, the continuous supply of charcoal and firewood not only contributes to the degradation of forests and the extinction of species, but also disrupts the livelihoods of forest-dependent families and exacerbates soil erosion. The charcoal production process is intrinsically damaging to both the environment and human well-being. Not only does it emit large quantities of CO2, contributing to atmospheric pollution, but it also presents health risks for both producers and users. The smoke and soot generated during charcoal production expose people to harmful substances, leading to adverse health effects and even premature death, particularly among children. This review also discusses the impact of this production and use on the education of women and children, who are responsible for cooking and harvesting firewood, resulting in a higher illiteracy rate among women. Faced with the need to take global action to mitigate the impact of climate change, global carbon dioxide emissions must be drastically reduced to meet the Paris Agreement target of zero net emissions by 2050. A practical and sustainable solution is discussed in this review as an alternative to traditional cooking systems namely solar cooking, which offers enormous potential, provided it is accessible, and is an excellent alternative to the heavy reliance on biomass for household energy needs in developing countries.
Chromium is a heavy metal used in tanneries, leather industries, electroplating, and metallurgical operations, but improper disposal of waste from these industries leads to environmental contamination. Chromium exists primarily in trivalent and hexavalent forms, with hexavalent chromium (Cr (VI)) being highly toxic. Cr (VI) is carcinogenic, damages fish gills, and negatively impacts crops. Considering these negative impacts of Cr (VI), several physical, chemical, and biological remediation methods have been implemented at contaminated sites, but in most instances, these methods could be uneconomical, highly labor-intensive, and not sustainable. Therefore, a crucial goal is to implement an effective and sustainable remediation technique with consideration of actual site conditions. The aim is to develop a sustainable remediation strategy for a hexavalent chromiumcontaminated site in Ranipet, Tamil Nadu. The comprehensive risk assessment for the site has depicted hazard quotients greater than 1 for both onsite and offsite conditions, indicating the necessity of remediation. To address this, it is suggested to build permeable reactive filters (PRFs) packed with scrap iron filings to reduce Cr (VI) to Cr (III), and succeeding filters with locally produced waste coconut shell biochar to aid in adsorption. The use of waste here aims to eliminate the need to procure any commercially available materials for remediation, completely cutting down the environmental impact of raw material extraction or processing. A continuous chambered set-up packed with contaminated soil and PRFs with biochar and iron filings aided in the decrease of the peak concentration of Cr (VI) by 61 % as compared to a set-up without intervention. Moreover, the outlet concentration after 7 days reduced to 0.08 mg/L, which was 97.6 % less than that in the set-up without intervention.
The frequent occurrence of extreme rainfall events often triggers levee slope failure (LSF), which, due to the levee effect, significantly damages the roads behind the levee. This paper presents a novel framework for the quantitative risk assessment of roads posed by LSF. Within the framework, the innovative integration of Monte Carlo simulation (MCS) and Material point method (MPM) provides a unique solution for simulating the complicated dynamic relationship between LSF and road destruction. MCS generates precise failure scenarios for MPM simulations, overcoming the limitations of traditional approaches in addressing uncertainty in complex scenario systems. With its technical superiority in capturing post-failure deformations, MPM offers critical insights for assessing road exposure and vulnerability. The framework also accounts for indirect losses from road disruptions, which have long been overlooked. The application of the framework to the risk assessment of the road behind the Shijiao Levee in the Pearl River Basin fully demonstrates its practicality and robustness. Compared to traditional risk assessment methods, the proposed framework provides a more refined dynamic evaluation, facilitating the formulation of more effective disaster mitigation strategies.
This study evaluates the impact of varying bedrock depths on local site amplification factors and their consequent influence on the vulnerability of buildings under seismic actions. An index-based methodology is implemented to analyze the seismic vulnerability of old masonry buildings in the historic center of Galata, & Idot;stanbul. As part of a site-specific analysis, soil models are developed to replicate a dipping bedrock at six different depths varying between 5 and 30 m beneath the ground surface. Consequently, potential damage scenarios are generated employing a seismic attenuation relation and damage distributions are compared for the cases with/without amplification effects. The findings point out that, the structural response undergoes the greatest amplification at a bedrock depth of 20 m, exceeding 1.6 and attaining its maximum value of 2.89 at the structural period of 0.22 s. The maximum shift in damage grades occurs for buildings with natural periods between 0.16 and 0.20 s on 15 m bedrock depth, whereas, for longer periods, the greatest increase occurs at 20 m bedrock depth compared to the scenarios without site amplification. As a result, this study emphasizes the significance of site-specific conditions that might amplify structural response and consequently, increase the seismic damage level in assessing the vulnerability of built heritage. By integrating geo-hazard-based evaluation into the large-scale seismic assessments, this study offers a framework for more accurate damage forecasting and highlights the need to include local site amplification effects in seismic risk mitigation plans, enhancing strategies for preserving built heritage.
Research on urban flood risk has highlighted the need for more comprehensive flood risk assessments in low-income and vulnerable communities. This study aims to examine the causes, impacts and existing flood risk management measures in the Somali region of Ethiopia. The study used a mixed research methodology, including a cross-sectional survey, to collect original qualitative and quantitative data.. In addition to flood risk and vulnerability assessment, the study evaluated urban flood risk management measures through soil protection service curve number, production distribution network and supply chain risk management methods.The results suggest that flooding in Dolo-Ado is increasing due to heavy rainfall and flooding, as well as inadequate flood control measures and geographical location. Soil Conservation Service Curve Number analysis shows that the arid landscape of Dolo-ado is predominantly shrub and barren with significant differences in land cover types. The low infiltration capacity, high runoff potential and frequent heavy rainfall are the main factors contributing to the area's high soil vulnerability to flash floodsConsequently, qualitative results also confirm that this has resulted in extensive infrastructure damage, displacement, loss of livelihoods, ecosystem disruption and disruption to community life, as well as water and health problems. In addition, flood risks are more severe for vulnerable urban communities, impacting services, the economy and the environment. Therefore, inadequate preventive measures for effective supply chain management are urgent and crucial for resilience. This study implies that urban planning and policies should be changed and prioritize the integration of production distribution networks and flood risk management in the supply chain to effectively mitigate floods. Climate change-responsive and integrated urban planning, improved drainage systems, early warning, emergency planning and community engagement are critical for flood preparedness, adaptation and resilience and require further research and modeling techniques.
The safe application of farm dairy effluent (FDE) to land has proven to be a challenge for dairy farmers and regulatory authorities throughout New Zealand. Poorly performing FDE systems can have deleterious effects on water quality because contaminants such as phosphorus, nitrogen and faecal microbes enter receiving waters with minimal attenuation by soil. We present a decision framework that supports good management of effluent, particularly during its application to land. The framework considers how FDE management can be tailored to account for soil and landscape features of a location that pose varying levels of contaminant transport risk. High risk soils and landscapes are vulnerable to direct losses via preferential and/or overland flow pathways and include sloping land (e.g. slopes greater than 7 degrees) and soils with mole drainage, coarse structure, poor natural drainage or low surface infiltration rates. Soil types that are well-drained with fine structure typically exhibit matrix flow characteristics and represent a relatively low risk of direct contaminant loss following FDE application. Our framework provides guidance on FDE application timings, rates and depths to different landform and soil types so that direct losses of contaminants to water are minimal and the opportunity for plant uptake of nutrients is enabled. Some potential limitations for using the framework include the potentially severe effects of animal treading damage during wet conditions that can reduce soil hydrological function and consequently increase the risk of overland flow of applied FDE. The spatial distribution of such treading damage should be considered in the framework's application. Another limitation is our limited understanding of the effects of soil hydrophobicity on FDE infiltration and application of the framework.
Flood hazard has resulted in the loss of thousands of lives and large-scale damage to properties. This study has explored, analyzed, and categorized the flood hazard and risk levels of Arba Minch City in South Ethiopia by integrating geospatial and Analytical Hierarchy Process techniques. Data were acquired from DEM with 12.5 m resolution, Landsat 8 OLI, ortho-rectified, and surveyed data from the Municipality. Slope, Elevation, Rainfall, Aspect, Curvature, Topographic Wetness Index, Topographic Roughness Index, Drainage Density, Distance from River, Soil Types, Land Use Land Cover, and Population Density parameters were used. Standard classification criteria were set based on literature and experts' judgment. Data were rasterized, resampled, and reclassified into five classes through the natural break method and readjustment. The flood hazard map was produced using the weighted overlay technique with hazard levels of low (7.39%), moderate (56.13%), and high (36.48%). Whereas, very low and very high remained nil. The flood risk levels were produced ascendingly as 2.4%, 17.3%, 17%, 44%, and 19.4%, respectively. The validity of the model was confirmed by the ROC-AUC Value of 0.923 being fitted with flood damage sites of Shara, Limat, Airport, Agriculture Research Center, Konso Sefer, Ashewamado, Gurba, and Arba Minch University campuses. Slope, elevation, rainfall, aspect and curvature were the top priority flood hazard parameters. The hazard map, population density, and land use land cover inputs have significant weights for flood risks. Thus, the study findings urge that the stakeholders should take integrated and consistent flood risk reduction and management measures.