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Özge Akboğa Kale, Tuğba Eskişar
Geotechnical site works are comprehensive, and they constitute the first step of the construction process. This study performs data mining of geotechnical works and analyzes the database for the root causes of accidents. The Occupational Safety and Health Administration (OSHA) was chosen for the 1984-2013 time frame with 247 cases. Descriptive statistical analyses were performed to discuss variables such as the end use of the work, project type and cost, soil type and condition, type and degree of injury, cause and type of accident, unsafe acts, and occupation and union status of the victim...
May 19, 2018: Industrial Health
Martyn Dade-Robertson, Helen Mitrani, Javier Rodriguez Corral, Meng Zhang, Luis Hernan, Aurelie Guyet, Anil Wipat
In this paper, we describe the first steps in the design of a synthetic biological system based on the use of genetically modified bacteria to detect elevated pressures in soils and respond by cementing soil particles. Such a system might, for example, enable a self- constructed foundation to form in response to load using engineered bacteria which could be seeded and grown in the soils. This process would reduce the need for large-scale excavations and may be the basis for a new generation of self-assembling and responsive bio-based materials...
April 13, 2018: Bioinspiration & Biomimetics
Sivakumar Gowthaman, Kazunori Nakashima, Satoru Kawasaki
Incorporating sustainable materials into geotechnical applications increases day by day due to the consideration of impacts on healthy geo-environment and future generations. The environmental issues associated with conventional synthetic materials such as cement, plastic-composites, steel and ashes necessitate alternative approaches in geotechnical engineering. Recently, natural fiber materials in place of synthetic material have gained momentum as an emulating soil-reinforcement technique in sustainable geotechnics...
April 4, 2018: Materials
Zhenying Zhang, Yingfeng Wang, Hui Xu, Yuehua Fang, Dazhi Wu
A landfill is one of the main sites for disposal of municipal solid waste and the current landfill disposal system faces several problems. For instance, excessive leachate water is an important factor leading to landfill instability. Understanding the permeability characteristics of municipal solid waste is a relevant topic in the field of environmental geotechnical engineering. In this paper, the current research progress on permeability characteristics of municipal solid waste is discussed. A review of recent studies indicates that the research in this field is divided into two categories based on the experimental method employed: field tests and laboratory tests...
March 1, 2018: Waste Management & Research
A K Mandal, Bala Ramudu Paramkusam, O P Sinha
Though the majority of research on fly ash has proved its worth as a construction material, the utility of bottom ash is yet questionable due to its generation during the pulverized combustion process. The bottom ash produced during the fluidized bed combustion (FBC) process is attracting more attention due to the novelty of coal combustion technology. But, to establish its suitability as construction material, it is necessary to characterize it thoroughly with respect to the geotechnical as well as mineralogical points of view...
April 2018: Waste Management & Research
Niteesh Singh Bonal, Bala Ramudu Paramkusam, Prabir Kumar Basudhar
The study aims to enhance the efficacy of surfactants using salt and multi-walled carbon nanotubes (MWCNT) for washing used engine oil (UEO) contaminated soil and compare the geotechnical properties of contaminated soil before and after washing (batch washing and soil washing). From batch washing of the contaminated soil the efficacy of the cleaning process is established. Contamination of soil with hydrocarbons present in UEO significantly affects its' engineering properties manifesting in no plasticity and low specific gravity; the corresponding optimum moisture content value is 6...
June 5, 2018: Journal of Hazardous Materials
Charles M R Graddy, Michael G Gomez, Lindsay M Kline, Sydney R Morrill, Jason T DeJong, Douglas C Nelson
Microbially Induced Calcite Precipitation (MICP) is a biomediated soil cementation process that offers an environmentally conscious alternative to conventional geotechnical soil improvement technologies. This study provides the first comparison of ureolytic bacteria isolated from sand cemented in parallel, meter-scale, MICP experiments using either biostimulation or bioaugmentation approaches, wherein colonies resembling the augmented strain ( Sporosarcina pasteurii ATCC 11859) were interrogated. Over the 13 day experiment, 47 of the 57 isolates collected were strains of Sporosarcina and the diversity of these strains was high, with 20 distinct strains belonging to 5 species identified...
April 3, 2018: Environmental Science & Technology
Rami Al-Ruzouq, Abdallah Shanableh, Maher Omar, Ghadeer Al-Khayyat
Waste management involves various procedures and resources for proper handling of waste materials in compliance with health codes and environmental regulations. Landfills are one of the oldest, most convenient, and cheapest methods to deposit waste. However, landfill utilization involves social, environmental, geotechnical, cost, and restrictive regulation considerations. For instance, landfills are considered a source of hazardous air pollutants that can cause health and environmental problems related to landfill gas and non-methanic organic compounds...
February 17, 2018: Environmental Monitoring and Assessment
Peter Zhang, Berk Tulu, Morgan Sears, Jack Trackemas
Room-and-pillar mining with pillar recovery has historically been associated with more than 25% of all ground fall fatalities in underground coal mines in the United States. The risk of ground falls during pillar recovery increases in multiple-seam mining conditions. The hazards associated with pillar recovery in multiple-seam mining include roof cutters, roof falls, rib rolls, coal outbursts, and floor heave. When pillar recovery is planned in multiple seams, it is critical to properly design the mining sequence and panel layout to minimize potential seam interaction...
January 2018: International Journal of Mining Science and Technology
Mengmeng Li, Chaolin Fang, Satoru Kawasaki, Varenyam Achal
Microbially induced calcium carbonate precipitation (MICP) results in the formation of biocement (BC). This process, also known as biocementation, is recently widely used to improve the strength and durability of building materials including soils. In the present study, effectiveness of biocement as admixture with fly ash (FA) was investigated as first few studies to improve geotechnical properties of expansive soils. Biocement precipitated by Bacillus megaterium was blend with four formulations of fly ash at concentrations of 0, 10, 25 and 50%, namely 0% FABC, 10% FABC, 25% FABC, and 50% FABC, respectively...
February 7, 2018: Scientific Reports
Ke Yin, Wei Ping Chan, Xiaomin Dou, Fei Ren, Victor Wei-Chung Chang
Incineration bottom ash (IBA) as potential material for land reclamation was investigated, based on leaching tests, sorption studies and simulation models. Based on batch and column leaching tests, Cr, Cu, Hg and Ni in the IBA leachates were measured as high as 510 μg/L, 20330 μg/L, 5.1 μg/L and 627 μg/L, respectively, presenting potential environmental risks. Sorption study was then performed with various concentrations of IBA leachates on sands and excavated materials. Partitioning coefficients of targeting metals were determined to be 6...
April 2018: Chemosphere
Dimitrios Terzis, Lyesse Laloui
We introduce the application of microbial-induced calcite precipitation via the ureolytic soil bacterium Sporosarcina Pasteurii in freeze-dried form, as a means of enhancing overall MICP efficiency and reproducibility for geotechnical engineering applications. We show that the execution of urea hydrolysis and CaCO3 precipitation persist as a "cell-free" mechanism upon the complete breakdown of rehydrated cell clusters. Further, strength and stiffness parameters of bio-cemented sands are determined...
January 23, 2018: Scientific Reports
Krishna R Reddy, Girish Kumar, Rajiv K Giri, B Munwar Basha
The performance of a bioreactor landfill is highly influenced by the simultaneous interactions of several coupled processes that occur within the landfill. In addition, the high uncertainty and spatial variability in the geotechnical properties of municipal solid waste (MSW) poses significant challenge in accurately predicting the performance of bioreactor landfills. In this study, a 2D coupled hydro-bio-mechanical (CHBM) model was employed to predict the behavior of MSW in bioreactor landfills. The numerical model integrated a two-phase flow hydraulic model, a plane-strain formulation of Mohr-Coulomb constitutive model, and a first order decay biodegradation model...
February 2018: Waste Management
Abdulla Al-Rawabdeh, Adel Moussa, Marzieh Foroutan, Naser El-Sheimy, Ayman Habib
Landslides are major and constantly changing threats to urban landscapes and infrastructure. It is essential to detect and capture landslide changes regularly. Traditional methods for monitoring landslides are time-consuming, costly, dangerous, and the quality and quantity of the data is sometimes unable to meet the necessary requirements of geotechnical projects. This motivates the development of more automatic and efficient remote sensing approaches for landslide progression evaluation. Automatic change detection involving low-altitude unmanned aerial vehicle image-based point clouds, although proven, is relatively unexplored, and little research has been done in terms of accounting for volumetric changes...
October 18, 2017: Sensors
Christine Erbe, Craig McPherson
Geotechnical site investigations prior to marine construction typically involve shallow, small-core drilling and standard penetration testing (SPT), during which a small tube is hammered into the ground at the bottom of the borehole. Drilling (120 kW, 83 mm diameter drillbit, 1500 rpm, 16-17 m drill depth in sand and mudstone) and SPT (50 mm diameter test tube, 15 mm wall thickness, 100 kg hammer, 1 m drop height) by a jack-up rig in 7-13 m of water were recorded with a drifting hydrophone at 10-50 m range...
September 2017: Journal of the Acoustical Society of America
Miriam Gonçalves Miguel, Rodrigo Paiva Barreto, Sueli Yoshinaga Pereira
The Ore Treatment Unit (UTM-Caldas), in the city of Caldas, Minas Gerais, Brazil, nowadays in decommissioning stage, was the first uranium extraction mine in Brazil. Several negative environmental impacts in the area have occurred, because of mining, treatment and beneficiation processes. Waste rock pile 4 (WRP-4) generates acid mine drainage (AMD), which is discharged in the Nestor Figueiredo retention pond (NFP). However, leakage of acid water by the NFP dam foundation has been constantly observed. Therefore, this research aimed to investigate a typical tropical soil, in order to use it as mineral liner for the NFP to minimize the leakage of acid water through the dam foundation and to retain predominant chemical species...
December 15, 2017: Journal of Environmental Management
Maryam Naeimi, Jian Chu
Dust is an environmental, geotechnical, health, and economical hazard. Fugitive dust emanating along transportation systems such as roads, railways, and airports especially can have significant impacts on health, safety, material loss, cost of maintenance, and interfere with the facilities. Quantitative studies on the effectiveness of the proper dust palliatives and their environmental impact have been studied with a number of biological and chemical methods. The objective of this study was to establish a method for using the microbial Induced calcium carbonate precipitation (MICP) approach to reduce the percent of mass loss against erosive force of wind regarding to the concentration and characteristics of aggregate used, climate, and traffic amounts...
October 2017: Environmental Science and Pollution Research International
Youngmin Choi, Hyunwook Choo, Tae Sup Yun, Changho Lee, Woojin Lee
Water-repellent soils have a potential as alternative construction materials that will improve conventional geotechnical structures. In this study, the potential of chemically treated water-repellent kaolin clay as a landfill cover material is explored by examining its characteristics including hydraulic and mechanical properties. In order to provide water repellency to the kaolin clay, the surface of clay particle is modified with organosilanes in concentrations (CO) ranging from 0.5% to 10% by weight. As the CO increases, the specific gravity of treated clay tends to decrease, whereas the total organic carbon content of the treated clay tends to increase...
December 2, 2016: Materials
Li-Hua Li, Yan-Jun Chen, Pedro Miguel Vaz Ferreira, Yong Liu, Heng-Lin Xiao
Waste tires have excellent mechanical performance and have been used as reinforcing material in geotechnical engineering; however, their interface properties are poorly understood. To further our knowledge, this paper examines the pull-out characteristics of waste tire strips in a compacted sand, together with uniaxial and biaxial geogrids also tested under the same conditions. The analysis of the results shows that the interlocking effect and pull-out resistance between the tire strip and the sand is very strong and significantly higher than that of the geogrids...
June 27, 2017: Materials
Natalia Rinaldi-Montes, Matt Rowberry, Carlos Frontera, Ivo Baroň, Javier Garcés, Jan Blahůt, Raúl Pérez-López, Christos Pennos, Xavi Martí
In this paper, a contactless positioning system is presented which has been designed to monitor the kinematic behavior of mechanical discontinuities in three dimensions. The positioning system comprises a neodymium magnet, fixed on one side of a discontinuity, and a magnetoresistive sensing array, fixed on the opposing side. Each of the anisotropic magnetoresistive sensors in the sensing array records the magnetic field along three orthogonal directions. The positioning system intrinsically generates compact data packages which are transmitted effectively using a range of standard wireless telecommunication technologies...
July 2017: Review of Scientific Instruments
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