Moderate Hazard Research Articles

Rock Slope Stability Assessment for Selected Sites at Imam Mohammed Road \ Sulaimaniyah Governorate \ Northern Iraq

A detailed engineering geological study was performed for rock slope stability for several selected sites at Imam Mohammed Road that connects Sulaimaniyah city and Darbandikhan town, the study included four sites in which a comprehensive survey was made for the rock slopes, the rocks forming them, and discontinuities affecting in them. The assessment of rock slope stability of the sites was executed through the stereographic projection, to determine the status of the slopes and discontinuities, field measurements revealed many occurred and probable failure types represented by the rock fall and sliding. The rock slopes were also classified based on three factors; divergence angle (parallel, oblique lateral, and orthogonal), Laterality (right and left emergent), and concordance (concordant and discordant). The rocks forming the slopes are described geometrically based on their color, grain size, texture, discontinuities, weathering, rock strength, lithology, and permeability. On the other hand, the risk of each site was also assessed depending on the Landslide Possibility Index (LPI), which showed that the first site lies within the (moderate hazard) category whereas the others lie within the (High hazard) category. Finally, some treatment strategies were proposed in order to stabilize the slopes and decrease the danger of their collapse on the road.

A Ranking Analysis of Geological and Engineering Factors of Historical Monuments’ Stability Response: A Case Study of Kyiv-Pechersk Lavra, Ukraine

The historical monuments of the National Preserve “Kyiv-Pechersk Lavra” play an important role in the context of preserving the UNESCO World Heritage. The scientific understanding of the buildings and structures safety management the priority of conducting repair and restoration works, the organization of their technical condition monitoring, and changes in the components of the geological environment in their locations is crucial. The purpose of this study is to identify potentially hazardous areas on the territory of the Lavra for the operation of structures by conducting a point-based integral assessment of the stability potential of the natural and technogenic system with the integration of geospatial methods and to rank the structures using the analytical hierarchy process. According to the modeling results by 17 stability factors and using ArcGIS, 37% (8.7 ha) of the Lavra territory is located in the zone of moderate hazard, 23% (5.4 ha) in the zone of potential hazard, where the manifestation and conditions of more than five dangerous engineering and geological processes intersect, and 40% (9.4 ha) in the zone of relative safety. In each zone, 10 representative structures were selected for ranking according to the stability of natural and technogenic operating conditions and their current technical condition, which is determined by nine criteria. The analysis using two methods identified the areas most at risk from seasonal fluctuations and possible military impacts and allowed us to scientifically substantiate the priority of repair and restoration work and the possibility of properly planning management measures for the selected structures, as well as to offer recommendations for improving the monitoring of the geological environment of the Lavra.

Assessment of landslide Possibility Index and Rockfall Hazard Rating System for Slopes in Qaywan Mountain, Sulaimani Governorate, Northeastern Iraq

The current study includes assessing road risks using a system Landslide Possibility Index (LPI) and Rockfall Hazard Rating System (RHRS) analysis along the Qaywan Mountain (anticline) main road 20 km north of SulaimaniGovernorate. Slope stability assessments consisted of seventeen stations along the main road in the study area. Along the outcropped rock units represented by formations, Balambo, Sarmord, Kometan, and Shiranish, a thorough discontinuity assessment and a regional survey of slopes were carried out. Along the cut slopes, rockfall is the primary type of failure, in addition to possibility types of landslide failures in the studied area is plane sliding, wedge sliding, and toppling because cutting rocks to build roads, slope direction and slope angle, dip and dip direction of discontinuities. The (LPI) indicates all the slopes studied in 17 sites in the surveyed area along the road were classified as high hazard. According to the analysis results of the RHRS, the score ranges between 177 and 375. Site no. 5 (375) has the highest rating value indicating a moderate hazard that requires remedial measures to be taken with a moderate level of urgency and site no.8 has the lowest value noted (177). It is the only site that falls under this rating, which is classified as a low hazard and slopes do not require detailed studies.

Microplastic assessment in remote and high mountain lakes of Gilgit Baltistan, Pakistan

Microplastic (MP) pollution is a critical environmental challenge worldwide, however limited research is reported in remote lakes of Pakistan. This study assessed MPs (>5 mm) prevalence, distribution and risk perspective in water and sediment of eight remote and high-altitude lakes (>1500 m above sea level) of Gilgit Baltistan, Pakistan. The lakes exhibited an average abundance of 152.6 ± 104.6 to 12.1 ± 7 MP/kg of dry sediments and 2 ± 0.9 to 17.1 ± 17.2 MP/L of surface water. MPs <200 μm dominated in both matrices. Surface water predominantly contained polyester and polypropylene, while polypropylene and polyethylene dominated in sediments. The gradient of elevation did not show any pronounced impact on the fiber loading or MP count in both matrices. Backward air mass trajectory revealed that air masses vastly travelled from western-Asia, Arabian sea and Bay of Bengal with an average transmission distance of 2500–3500 km (500 m a.s.l) that can be a potential deposition MP source in the area. Pollution Load Index of the lakes were >1 exhibiting pollution. All other lakes except Batura and Borith manifested a moderate hazard index. Naltar lake along with aforementioned two lakes also manifested high polymer toxicity. Further research should emphasize understanding the mechanisms and biotic interactions in high-mountain ecosystems.

Flood Modelling of Madi River Using HEC-RAS by Rain on Grid Approach

Indispensable for prognosticating flood impact in areas with limited data availability, reliable flood models are crucial for the analysis and mitigation of flood hazard. This study provides insight to accurately analyse flood scenarios by preparing a well calibrated 2D hydraulic model in HEC-RAS along with the Rain on Grid approach, which is subsequently used for hazard map preparation of Madi River. Hazard classification of flood depth indicated that for a 20-year return period, Moderate hazard levels covered 16.499%, High hazard levels covered 14.831%, and Very High hazard levels covered 68.670% of the total inundated area with reference to the depth hazard categories. Since, significant portion of the inundated area is classified as Very High Hazard; the finding of this research emphasizes the need of effective mitigation measure and provides essential insights crucial for flood risk assessment.

Analisis Bahaya Bencana Gempa Bumi di Wilayah Kabupaten Pesisir Selatan

This study aims to determine the earthquake hazard levels in Pesisir Selatan Regency, West Sumatra Province, by identifying the Peak Ground Acceleration (PGA) values and the distribution of earthquake hazard levels. The type of research used is quantitative descriptive analysis and spatial analysis. The method employed in this study is Probabilistic Seismic Hazard Analysis (PSHA). To determine the Peak Ground Acceleration values, parameters such as earthquake location, occurrence time, and earthquake magnitude are used. For determining the earthquake hazard distribution, data on Ground Amplification Factor (GAF) is utilized. The results of this study show that the distribution of Peak Ground Acceleration in the study area ranges from 0.17 g to 0.93 g. The value of 0.17 g is found in Koto XI Tarusan District, while the highest value is observed in Silaut District. Additionally, the distribution of earthquake hazard levels shows that areas with low hazard level cover 697.04 km², moderate hazard level covers 4150.49 km², and high hazard level covers 1201.81 km². This study provides earthquake hazard maps that can be used for mitigation and planning in the region.

Mortality case due to minimal bentazone intoxication.

Bentazone is a widely used herbicide and is considered a moderate hazard. Fatalities are rarely reported, with reports of deaths occurring in doses of 200 ml or more. In some literature, it is accompanied by generalized rigidity. Malignant hyperthermia (MH) is a pharmacogenetic diseases that presents a hypermetabolic response to anesthetic gases or depolarizing muscle relaxant due to calcium channel dysfunction. The classic symptom of MH include hyperthermia and muscle rigidity. In this article, we report a case of a 65-year-old man who died 4 hours after presenting to the emergency department after taking approximately 75 ml of Basagran M60 (bentazone 33.6%, 25.2 g). This is the smallest dose (364 mg/kg) reported in a fatal case to date. Electrocardiogram changes, including QRS widening and QT prolongation, were present, and hypocalcemia was confirmed. We propose the possibility that bentazone intoxication causes patient deterioration by a mechanism similar to malignant hyperthermia.

Environmental exposure patterns to 94 current-use pesticides in women of reproductive age who are preparing for pregnancy

Current-use pesticides (CUPs), including insecticides, fungicides, and herbicides, are extensively employed in agriculture to manage pests, diseases, and weeds. Nonetheless, their widespread application raises significant concerns regarding potential impacts on human health, particularly with reproductive health. This study focuses on exploring the landscape of CUP exposure among pre-pregnancy women. Based on a cohort study comprising 354 pre-pregnancy women of reproductive age in Beijing, China, we measured the concentrations of 94 CUPs in serum and conducted an in-depth analysis of exposure profiles, health risks, and contributing factors. The results revealed that the serum of pre-pregnancy women was contaminated with CUPs, of which the median concentrations ranged from 0.114 (fenamiphos-sulfone) to 61.2 ng/L (mefenacet). Among the 94 CUPs, 54 exhibited detection rates higher than 50 %, including 26 insecticides, 14 fungicides, and 14 herbicides. The exposure concentration profile highlighted that the insecticides contributed 56 % to the total CUP concentration percentages, with organophosphate insecticides being the primary contributors within this category (63.0 %). The average daily intake (ADI) of CUPs ranged from 2.23 to 16,432.28 ng/kg, while diflubenzuron had the highest ADI. Health risk assessments showed that exposure to a combination of total insecticides or herbicides poses a moderate risk for 15.8 % and 30.2 % of women, with mefenacet being the most significant, which showed moderate hazard in 29.4 % of participants. The overlap analysis showed that methiocarb-sulfone, diflubenzuron, and mefenacet were the dominant pesticides. In addition, maternal age, annual income level, smoking, and vitamin B12 supplementation were associated with serum CUP concentrations. Our study contributes a novel and comprehensive exposure profile of CUPs in pre-pregnancy women in northern China, providing valuable insights for evaluating the potential consequences of pre-pregnancy exposure on reproductive health. SynopsisWe provided a comprehensive exposure landscape, health effects, and influential factors of 94 current-use pesticides among pre-pregnancy women in China.

EROSION HAZARD LEVEL PREDICTION IN LAKE OF SENTARUM AREA

The Sentarum Lake region, a conservation area in Kalimantan, is integral to the Kapuas River Basin, which is recognized nationally. Ensuring its sustainability demands diverse studies, including erosion risk assessment. Accurate predictions are vital due to the region's ecosystem role in West Kalimantan. Estimating erosion magnitude provides crucial data on sedimentation, which impacts the sustainability of endemic flora and fauna. This study aims to (a) pinpoint erosion factors in Lake of Sentarum, (b) assess erosion hazard levels, (c) create an erosion hazard map with ArcGIS, and (d) prescribe soil conservation measures. Methods encompassed (a) field and institutional surveys for data gathering and (b) the USLE method for erosion hazard analysis. Identifying erosion factors in the Sentarum Lake area reveals rainfall, soil type, slope, and land cover as significant influencers. Analysis indicates heavy erosion hazards for Inceptisol and Utilosol soils, except in areas with primary dryland forest or flat-sloped dryland agriculture where hazards are heavy. Peat-containing soils are especially prone to erosion. Oxisol soils on flat slopes with agricultural land cover face heavy hazards, while moderate hazards occur in dryland agriculture on steeper slopes. The region faces considerable erosion risk, particularly in specific soil and land cover conditions, emphasizing the need for targeted soil conservation measures. Thus, the Sentarum Lake area is highly susceptible to erosion, necessitating specific soil conservation measures. Structural methods like constructing bench terraces prove more effective than non-structural ones, such as tillage and contour line planting, reducing erosion hazard by approximately 96%.

New insights into the impact of leachates from in-field collected plastics on aquatic invertebrates and vertebrates

The impact of leachates from micronized beached plastics of the Mediterranean Sea and Atlantic Ocean on coastal marine ecosystems was investigated by using a multidisciplinary approach. Chemical analysis and ecotoxicological tests on phylogenetically distant species were performed on leachates from the following plastic categories: bottles, pellets, hard plastic (HP) containers, fishing nets (FN) and rapido trawling rubber (RTR). The bacteria Alivibrio fischeri, the nauplii of the crustaceans Amphibalanus amphitrite and Acartia tonsa, the rotifer Brachionus plicatilis, the embryos of the sea urchin Paracentrotus lividus, the ephyrae of the jellyfish Aurelia sp. and the larvae of the medaka Oryzias latipes were exposed to different concentrations of leachates to evaluate lethal and sub-lethal effects. Thirty-one additives were identified in the plastic leachates; benzophenone, benzyl butyl phthalate and ethylparaben were present in all leachates. Ecotoxicity of leachates varied among plastic categories and areas, being RTR, HP and FN more toxic than plastic bottles and pellets to several marine invertebrates. The ecotoxicological results based on 13 endpoints were elaborated within a quantitative weight of evidence (WOE) model, providing a synthetic hazard index for each data typology, before their integrations in an environmental risk index. The WOE assigned a moderate and slight hazard to organisms exposed to leachates of FN and HP collected in the Mediterranean Sea respectively, and a moderate hazard to leachates of HP from the Atlantic Ocean. No hazard was found for pellet, bottles and RTR. These findings suggest that an integrated approach based on WOE on a large set of bioassays is recommended to get a more reliable assessment of the ecotoxicity of beached-plastic leachates. In addition, the additives leached from FN and HP should be further investigated to reduce high concentrations and additive types that could impact marine ecosystem health.

Abstract PO2-25-09: The hidden costs of beauty: An evaluation of breast cancer risk for Black women

Abstract The Black identity, hair product use, and breast cancer scale (BHBS) was developed and previously validated to evaluate the relationship between identity, hair product use, and breast cancer risk for Black women. Black women are disproportionately affected by breast cancer compared to other racial/ethnic groups, with a mortality rate of 40% higher than all other groups. Endocrine Disrupting Chemicals (EDCs) are present in many hair care products and have been linked to several health issues including breast cancer. Due to these health inequities and the complexity of how cultural norms shape Black women’s hair product usage, the purpose of this study was to assess the reliability of the BHBS for intervention planning and evaluate the hazard scores of hair products used by Black women. Methods: Participants were recruited using purposive convenience sampling techniques. The 11-item BHBS includes two subscales: five items measuring sociocultural perspectives about hair and identity (S1) and six items assessing perceived breast cancer risk related to hair product use (S2). To determine reliability, the BHBS was administered twice over a three-week period with sociodemographic factors obtained in the initial data collection phase. All statistical analyses, including descriptive statistics and test-retest reliability (Pearson correlations) were conducted using SPSS version 26. The Environmental Working Group's (EWG's) Skin Deep® database was used to determine hazard scores of hair products used by participants. Products are rated on a 10-point scale with low (0-2), moderate (3-6), and high hazard (7-10) scores. Results: Twenty-three (86.9% African, African American &amp; Caribbean; 13% multiracial) female participants completed the study. Their age ranged from 18-63 years (30.78, SD= 15.40), 47.8% reported an income of less than $25,000, and 34.8% completed some college education. Both subscales demonstrated highly significant and strong reliability (S1: r=.82, p&amp;lt; .001; S2: r=.88, p&amp;lt; .001). Participants primarily used conditioners (91.3% used wash out and 60.9% used leave-in), and professional hair dyes (34.8%). There was also a high frequency of non-use (91.3%) of do-it-yourself relaxers and hair dye kits. We evaluated 40 products across three categories including wash out conditioners, leave-in conditioners and other hair products (e.g., styling gels, shampoo, and hair oils), of which most had a moderate hazard rating of 5 denoting ingredients of health concerns (e.g., parabens, fragrance, and phenoxyethanol). Additionally, of the 22 company brands analyzed, only 10 (45%) are Black owned or founded. Conclusions: The BHBS is a valid and reliable instrument to assess sociocultural perspectives about hair, identity and perceived breast cancer risk. Black women use hair products including relaxers, hair dyes, and conditioners that contain EDCs that may be harmful to their health including risk for breast cancer. The BHBS will be used to evaluate psychosocial interventions that address the unique needs of Black women including exposure to EDCs from hair product use and breast cancer risk. Citation Format: Nicole Sarkaria, Marissa Ericson, Abigail Lopez, Dede Teteh. The hidden costs of beauty: An evaluation of breast cancer risk for Black women [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-25-09.

Indoor and outdoor air quality in street corner kiosks in a large metropolitan area

Poor air quality in workplaces constitutes a great concern on human health as a good fraction of our time is spent at work. In Greece, very unique workplaces are the street corner kiosks, which are freestanding boxes placed on sidewalks next to city streets and vehicular traffic, where one can find many consumer goods. As such, its employees are exposed to both outdoor and indoor air pollutants. Very few studies have examined the occupational exposure of kiosk workers to air pollutants, and thus the magnitude of this unique indoor and outdoor exposure remains unknown. The objective of this study is to investigate and compare the levels of indoor and outdoor particulate matter (PM10 and PM2.5), ultrafine particles (UFPs) and black carbon (BC) in different kiosks located in Athens, Greece, in urban-traffic and urban-background environments. Continuous measurements of the above-mentioned pollutants were carried out on a 24-h basis over 7 consecutive days at three kiosks from September to October 2019. Indoor PM10 concentrations in the urban kiosk ranged from 19.0 to 44.0 μg/m3, PM2.5 values ranged from 14.0 to 33.0 μg/m3, whereas BC concentrations ranged from 1.2 to 7.0 μg/m3 and UFPs from almost 9.5 to 47.0 × 103 pt/cm3. Outdoor PM10 and PM2.5 measurements ranged from 29.0 to 59.0 μg/m3 and from 22.0 to 39.0 μg/m3, respectively. BC outdoor concentrations ranged from 1.1 to 2.2 μg/m3. The mean hazard quotient (HQ) for PM10 (4.9) and PM2.5 (4.7) among all participants was >1. The health risk of exposure to PM10 and PM2.5 was found to be at moderate hazard levels, although in some cases we observed HQ values higher than 10 due to high PM10 and PM2.5 concentrations in the kiosks. Overall our study indicates that people working at kiosks can be exposed to very high concentrations on particulate pollution depending on a number of factors including the traffic that strongly depends on location and the time of the day.

Interactions between microplastics and Culex sp. larvae in wastewater.

Microplastics (MPs) are a growing issue because they endanger both aquatic organisms and humans. Studies have indicated that wastewater treatment plants (WWTPs) are one of the major contributors to MPs in the environment. However, studies on the abundance of MP contamination in WWTPs and its transmission into aquatic organisms are still scarce, especially in Egypt. The goal of this study was to examine the temporal fluctuations in the distribution of MPs in surface water and the dominant macroinvertebrate fauna (Culex sp. larvae) in a fixed wastewater basin in Sohag Governorate, Egypt. The average of MPs in the surface water was 3.01 ±0.9 particles/L. The results indicated to seasonal variation of MP abundance in the wastewater basin that was significantly higher in winter than in the other seasons. The risk index for polymers (H), pollution load index (PLI), and potential ecological risk index (RI) were used to assess the degree of MP contamination. The basin has moderate H values (<1000) because of the presence of polymers with moderate hazard scores such as polyester (PES), polyethylene (PE), and polypropylene (PP). According to the PLI values, surface water is extremely contaminated with MPs (PLI: 88 to 120). The RI values of surface water showed higher ecological risk (level V). MPs in Culex sp. larvae were seasonally changed with an 85% detection rate, and an abundance average of 0.24 ±0.65 particles/ind, MP concentration in Culex sp. larvae was influenced by the MP characters (shape, color, and polymer). The larvae of Culex sp. showed a greater preference for black and red fibrous polyester (PES) with sizes (<1000 μm) of MPs. These findings suggest that Culex sp. larvae prefer ingesting MPs that resemble their food. It is possible to overestimate Culex sp.'s preference for lower sizes because of their catabolism of MPs. To better understand the preferences of Culex sp. larvae for MPs, further controlled trials should be conducted. PRACTITIONER POINTS: Wastewater is highly contaminated with microplastics (MPs) in the different seasons. First report of detection of the seasonal abundance of MP in Culex sp. larvae. Culex sp. larvae showed a stronger feeding preference for MPs with specific characteristics. Smaller size and blue polyester fibers were the dominant characteristics of MPs in wastewater.

Work accident risk analysis using HIRARC and FTA methods (Case study: Suwarno Meubel)

Suwarno Meubel is a business engaged in furniture production, which has risks related to occupational health and safety including workers carrying heavy wood manually, cutting wood with a table saw, painting wood with a spray gun, and so on. The purpose of this study is to find out the potential hazards that exist in each job and find the root causes of work accidents and then provide suggestions for improvements. The research method used is Hazard Identification Risk Assessment and Risk Control (HIRARC) to identify hazard risks and risk assessments for each job, after that, jobs with extreme values will be further analyzed using the Fault Tree Analysis method (FTA). The results of this study found 9 low categories of hazard risks, 12 moderate hazard categories, 4 high hazard categories, and 1 extreme hazard category. Risks in the extreme category were analyzed and found that there were 7 basic events, namely fatigue, lack of focus, lack of training, a limited number of PPE (goggles), no safety equipment on the machine, and no work procedures. The proposed controls are in the form of administrative control, PPE, and engineering.

Flash Flood Hazard Assessment along the Red Sea Coast Using Remote Sensing and GIS Techniques

The Egyptian Red Sea coast is periodically exposed to flash floods that cause severe human and economic losses. That is due to its hydro-geomorphological characteristics. Therefore, identifying flash flood hazards in these areas is critically important. This research uses an integrated approach of remote sensing data and GIS techniques to assess flash flood hazards based on morphometric measurements. There are 12 drainage basins in the study area. These basins differ in their morphometric characteristics, and their main streams range between the 4th and 7th order. The morphometric parameter analysis indicates that three wadis are highly prone to flooding, five wadis are classified as moderate hazard, and four wadis are rated under low probability of flooding. The study area has a probability offlooding, which could cause serious environmental hazards. To protect the region from flash flood hazards and the great benefit of rainwater, the study recommended detention, crossing, diversion, and/or storage of the accumulated rainwater by building a number of dams or culverts along the main streams of wadis to minimize the flooding flow.

Assessing Hazardous Manifestations of Horizontal Channel Deformations in Rivers of the Ob–Irtysh Basin

Bank erosion is a hazardous manifestation of channel processes, which are widespread on the rivers of the Ob–Irtysh basin and pose both real and potential danger. The most widespread form of channel transformation in the rivers of the basin is the development of channel bends, bends of branches of a bifurcated channel and bends of branches of floodplain–channel bifurcations, as well as branches of channel (insular) bifurcations due to bank erosion, which leads to a directed change in their morphological parameters. The channel stability is a key characteristic for assessing the hazard of channel processes. The largest rivers of the basin (the Ob and Irtysh) have relatively stable channels, corresponding to a moderate hazard. The medium and large rivers, in which the hazard of channel processes was evaluated by points, show a relatively low level (mostly, 1–2 points), which increases downstream to reach 3 points in the lower parts of large rivers (the Tom and Chulym). Overall, the intensity of shore erosion, and, accordingly, the hazard of horizontal channel deformations, in the rivers of the Ob–Irtysh basin decrease northward and toward the Ob–Irtysh interfluve. The obtained results can be used for the safe use of water ways and near-river areas as well as for the effective management of hazardous manifestations of channel processes.

The Landslide Threat Evaluation and Zoning in The Birbir Mariam District, Gamo Highlands, Ethiopia Great Rift Valley Escarpment Using Slope Susceptibility Analysis and Geospatial Techniques

The current research focuses on landslide assessment and hazard zonation in the Birbir Mariam district of the Gamo Highlands. The study examined landslide causative factors and used the slope susceptibility evaluation parameter to create a landslide hazard zonation covering an area of 110 square kilometers. The landslide hazard zonation was classified using facet-wise observation. As a result, the intrinsic and external causal parameters of score schemes have been held responsible for slope instability. Inherent causative elements consist of slope geometry, slope material (rock or soil), structural discontinuities, land use or land cover, and groundwater conditions. Rainfall and human interest have seemed like external elements. The intrinsic and external triggering elements for every facet (a total of 106) were rated for their contribution to slope instability. Finally, an evaluated landslide hazard value was calculated and classified into three landslide hazard classes. According to the findings, the area has a high hazard zone of 18.87 percent (20.76 km2), a moderate hazard zone of 54.72 percent (60.19 km2), and a low hazard zone of 26.41 percent (29.05 km2). The methodology employed in this investigation, as well as the resulting landslip susceptibility zonation map, were both reliable and applicable to other places with similar geology and topographic circumstances. &#x0D; Keywords: Landslide evaluation, Slope stability, Landslide, Hazard zonation, Ethiopia

Tunnel Stability Analysis Under Seismic Load Using Finite Element Method: A Case Study of Spillway Tunnel, Sidan Dam, Bali, Indonesia

The location of the Sidan Spillway Tunnel, as shown on the Earthquake Hazard Zone Map of Bali Island, is in a moderate hazard zone. The support system of the spillway tunnel of the Sidan Dam, Indonesia, was empirically designed based on rock mass classification systems. The objective of this research was to verify the performance of the proposed support system by a numerical method considering the uncertainty in using rock mass classification systems for designing a tunnel support system. In addition, being located in an active seismic region, the seismic load was not considered in the empirical tunnel support design. The proposed tunnel support design was numerically modeled in two dimensions using a finite element method and subjected to a seismic load obtained from probabilistic seismic hazard analysis. A numerical analysis without seismic load was also conducted for comparison. Phase2 software was used for the tunnel stability analysis. The input parameters in the numerical analysis were derived from field investigations (surface engineering geological mapping and evaluation of drilling cores) and laboratory tests. The spillway tunnel area consists of pyroclastic rocks, and the Generalized Hoek-Brown Failure Criterion was selected for the strength parameter of rocks. The suggested support designs are systematic rock bolts (20 mm diameter fully grouted), wired mesh, shotcrete, and steel ribs at specific locations. The numerical models determined that applying the proposed tunnel support system recommended based on the empirical method resulted in a roof strength factor of more than 1.5 under static load & 1.1 under seismic load and roof displacements lower than a 10 cm maximum displacement at every stage of construction. The results verify that the tunnel construction will be stable and fulfill the required safety standard, both under and without seismic loads.

Hazard Identification Risk Assessment and Determining Control (HIRADC) Method for Shoe Cutting Dies Production

Along with high orders from customers for shoe products in apparel companies, the production department must also support productivity results. The production process has experienced several problems, including the number of work accidents and potential levels of work accidents, and the absence of safe work accident control measures in the cutting die area for the shoe production process. The purpose of this study is to analyze the types of work accidents and provide recommendations for controlling sources of hazard to reduce or eliminate the level of risk involved in the shoe molding process. The method used in this study uses the Hazard Identification Risk Assessment and Determining Control (HIRADC) method combined with the Focus Group Discussion (FGD) method. The findings of this study have obtained data before repair with 16 hazard potentials consisting of 6 medium hazard potentials and 10 low hazard potentials. Improvements that have been made in accident risk control for each potential hazard include technical controls, administrative controls, and document controls. The results of this study resulted in a reduction in the risk of work accidents after repairs to 16 low hazard potentials and no moderate hazard potentials. So from these results, it can be concluded that the decrease in risk level from medium risk to low risk proves the success of corrective actions.

Assessing building's post-earthquake functional recovery accounting for utility system disruption

Experience from past earthquakes has demonstrated the need to account for design goals beyond safety, known as functional recovery objectives, in the interest of community resilience. Frameworks have been proposed in the literature to assess the post-earthquake functional recovery of a building, but without accounting for utility systems’ disruption, which may be a key contributor to determining when a building is functional. This paper integrates a previously proposed probabilistic method for estimating the post-earthquake restoration of critical utility services with an individual building's functional recovery assessment framework. The integration was performed by incorporating utilities into the building system fault trees embedded into a functional recovery framework for various building occupancies (residential and commercial office buildings). Once incorporated, the results are used to interrogate the functional recovery of a reinforced concrete building, and the recovery time results were presented for seven cases investigating contributing factors in the functional recovery results including the number of crews available for lifeline restoration, the effect of low-quality service on meeting tenant requirements for elevators, heating ventilation and air conditioning (HVAC), plumbing and electrical systems, consideration of fire watch, the effect of building seismic retrofit, as well as different cases of fragility functions for the lifeline systems. Results showed that utility systems’ disruption does not have a significant impact on the recoccupancy of a building because only one utility-dependent building system (fire suppression) is needed for the building's safety. Unlike reoccupancy, utility systems are significant for functional recovery, mainly at moderate hazard levels because, at these levels, lifeline networks could be damaged without significant building damage, such that the lifeline systems restoration governs. Buildings with more restrictive tenant requirements are more sensitive to tenant disruptions.