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Effects of oil contamination and bioremediation on geotechnical properties of highly plastic clayey soil

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Journal of Rock Mechanics and geotechnical Engineering 2021年第3期13卷 653-670页

作者： Araz Salimnezhad Hossein Soltani-Jigheh Ali Abolhasani Soorki Department of Civil Engineering Ozyegin UniversityCekmekoyIstanbul34794Turkey Department of Civil Engineering Azarbaijan Shahid Madani UniversityTabrizIran ACECR-Research Institute of Applied Sciences Shahid Beheshti UniversityTehranIran

Leakage of oil and its derivatives into the soil can change the engineering behavior of soil as well as cause environmental disasters.Also,recovering the contaminated sites into their natural condition and making contaminated materials as both environmentally and geotechnically suitable construction materials need the employment of remediation techniques.Bioremediation,as an efficient,low cost and environmentalfriendly approach,was used in the case of highly plastic clayey soils.To better understand the change in geotechnical properties of highly plastic fine-grained soil due to crude oil contamination and bioremediation,Atterberg limits,compaction,unconfined compression,direct shear,and consolidation tests were conducted on natural,contaminated,and bioremediated soil samples to investigate the effects of contamination and remediation on fine-grained soil properties.Oil contamination reduced maximum dry density(MDD),optimum moisture content(OMC),unconfined compressive strength(UCS),shear strength,swelling pressure,and coefficient of consolidation of soil.In addition,contamination increased the compression and swelling indices and compressibility of soil.Bioremediation reduced soil contamination by about 50%.Moreover,in comparison with contaminated soil,bioremediation reduced the MDD,UCS,swelling index,free swelling and swelling pressure of soil,and also increased OMC,shear strength,cohesion,internal friction angle,failure strain,porosity,compression index,and settlement.Microstructural analyses showed that oil contamination does not alter the soil structure in terms of chemical compounds,elements,and constituent minerals.While it decreased the specific surface area of the soil,and the bioremediation significantly increased the mentioned parameters.Bioremediation resulted in the formation of quasi-fibrous textures and porous and agglomerated structures.As a result,oil contamination affected the mechanical properties of soil negatively,but bioremediation improved these properties.

关键词： Oil contamination Bioremediation geotechnical properties Clay mineralogy Soil microstructure Highly plastic soil Fine-grained clayey soil Marl

Assessment of geotechnical properties of Laki Limestone for Coarse Aggregate, Nooriabad, Jamshoro Sindh, Pakistan

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Advances in Geological and geotechnical Engineering Research 2022年第2期4卷 37-47页

作者： Sumaira Asif Khan Adnan Khan Department of Geology University of KarachiKarachiSindhPakistan

Present study is aimed at assessment of geotechnical properties of Laki limestone as coarse aggregate which is being quarried in Nooriabad area,Sindh,Pakistan.Coarse aggregate samples(n=20)of limestone were collected for the evaluation of physico-mechanical properties of the aggregate.Petrographic analysis revealed that the aggregate comprises of hard,compact,massive,crystalline and fossiliferous limestone.It is devoid of any reactive silica(chert,chalcedony)and other harmful constituents like clays or organic matter.Average values of specific gravity,absorption,bulk density,void content and combined index(EI+FI)of collected samples are 2.5,2.1%,1.54 g/cc,38.55%and 13.04%respectively.The values of specific gravity(2.3-2.9),absorption(0-8%),bulk density(1.28 g/cc-1.92 g/cc)and void content(30%-45%)are varying within the range of normal weight aggregate as per American concrete institute(ACI)specifications.On the other hand,absorption values of aggregate samples are slightly higher(2.1%)than the reference range(2%)but meet other requirements.Mechanical properties including aggregate impact value(8.58%),aggregate crushing value(26.66%),Loss Angeles abrasion value(24.77%),sodium sulfate soundness(4.72%),water soluble sulfate(0.006%)and water soluble chloride(0.005%)are found to be within corresponding guidelines set by ASTM.On the other hand,average carbonate content is found to be 89.64%indicating that Laki limestone is of slightly low purity.Except absorption,all physical and mechanical properties lie within specified ranges.It is concluded that Laki limestone is suitable for use as road aggregate and concrete mix design.

关键词： Laki limestone Coarse aggregate geotechnical properties Nooriabad

Geo-environmental application of municipal solid waste incinerator ash stabilized with cement

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Journal of Rock Mechanics and geotechnical Engineering 2017年第2期9卷 370-375页

作者： Davinder Singh Arvind Kumar Department of Civil Engineering Dr. B.R. Ambedkar National Institute of TechnologyJalandharPunjabIndia

The behavior of soluble salts contained in the municipal solid waste incinerator(MSWI) ash significantly affects the strength development and hardening reaction when stabilized with cement.The present study focuses on the compaction and strength behavior of mixed specimens of cement and MSWI ash.A series of indices such as unconfined compressive strength,split tensile strength,California bearing ratio(CBR) and pH value was examined.Prior to this,the specimens were cured for 7 d,14 d,and 28 d.The test results depict that the maximum dry density(MDD) decreases and the optimum moisture content(OMC)increases with the addition of cement.The test results also reveal that the cement increases the strength of the mixed specimens.Thus,the combination of MSWI ash and cement can be used as a lightweight filling material in different structures like embankment and road construction.

关键词： Municipal solid waste incinerator(MSWI) ash Cement Compaction Stabilization California bearing ratio(CBR) test geotechnical properties

Aggregate Suitability Assessment of Wargal Limestone for Pavement Construction in Pakistan

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Open Journal of Civil Engineering 2022年第1期12卷 56-74页

作者： Javid Hussain Jiaming Zhang Fitriani Fitria Muhammad Shoaib Hadi Hussain Ali Asghar Sadam Hussain Geological Engineering China University of Geosciences Wuhan China School of Geophysics and Geomatics China University of Geosciences Wuhan China State Key Laboratory of Hydraulic Engineering Simulation and Safety School of Civil Engineering Tianjin University Tianjin China Department of Oil and Gas Engineering China University of Geosciences Wuhan China

This paper presents the evaluation of the potential aggregate source for pavement construction in Pakistan. Recently the demand for construction materials has been increased significantly due to the establishment of the China-Pakistan Economic Corridor (CPEC) Projects. Therefore, it is essential to look for new resources of construction materials along with the CPEC routes in consideration of this increasing demand. In this context, a Physical and Mechanical characterization investigation is carried out on the Permian Wargal Limestone from Zaluch Nala, Salt Range to explore their potential to utilize as construction materials. The studied samples have tolerable values for all standard engineering parameters, proposed by various national and international agencies such as AASHTO, ASTM, BS, and NHA. Furthermore, as a performance indicator of aggregate overall quality, the evaluated mechanical qualities were integrated into a single characteristic, Toughness Index (TI). The TI values also suggested that the Permian Wargal limestone aggregates meet international quality standards for pavement construction. On the basis of geotechnical testing and Toughness Index (TI), the late Permian Wargal limestone, Zaluch Nala, Salt Range, is strongly recommended as a potential aggregate resource for mega projects such as the China-Pakistan Economic Corridor (CPEC) and other construction projects.

关键词： CPEC Potential Aggregates geotechnical properties Toughness Index (TI) Wargal Limestone

Sound velocity and related properties of seafloor sediments in the Bering Sea and Chukchi Sea

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Acta Oceanologica Sinica 2015年第5期34卷 75-80页

作者： MENG Xiangmei LI Guanbao HAN Guozhong KAN Guangming First Institute of Oceanography State Oceanic Administration Key Laboratory of Marine Sedimentology and Environmental Geology State Oceanic Administration

The Bering Sea shelf and Chukchi Sea shelf are believed to hold enormous oil and gas reserves which have attracted a lot of geophysical surveys. For the interpretation of acoustic geophysical survey results, sediment sound velocity is one of the main parameters. On seven sediment cores collected from the Bering Sea and Chukchi Sea during the 5th Chinese National Arctic Research Expedition, sound velocity measurements were made at 35, 50, 100, 135, 150, 174, 200, and 250 kHz using eight separate pairs of ultrasonic transducers. The measured sound velocities range from 1 425.1 m/s to 1 606.4 m/s and are dispersive with the degrees of dispersion from 2.2% to 4.0% over a frequency range of 35-250 kHz. After the sound velocity measurements, the measurements of selected geotechnical properties and the Scanning Electron Microscopic observation of microstructure were also made on the sediment cores. The results show that the seafioor sediments are composed of silty sand, sandy silt, coarse silt, clayey silt, sand-silt-clay and silty clay. Aggregate and diatom debris is found in the seafloor sediments. Through comparative analysis of microphotographs and geotechnical properties, it is assumed that the large pore spaces between aggregates and the intraparticulate porosity of diatom debris increase the porosity of the seafioor sediments, and affect other geotechnical properties. The correlation analysis of sound velocity and geotechnical properties shows that the correlation of sound velocity with porosity and wet bulk density is extreme significant, while the correlation of sound velocity with clay content, mean grain size and organic content is not significant. The regression equations between porosity, wet bulk density and sound velocity based on best-fit polynomial are given.

关键词： Bering Sea Chukchi Sea sound velocity geotechnical properties microstructure

Engineering Geological and geotechnical Investigations for Design of Oxygen Plant

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International Journal of Geosciences 2022年第4期13卷 303-318页

作者： Khaleel Hussain Dou Bin Javid Hussain Syed Yasir Ali Shah Hadi Hussain Altaf Hussain Sadam Hussain Geological Resources and Engineering China University of Geosciences Wuhan China Geological Engineering China University of Geosciences Wuhan China Oil and Gas Engineering China University of Geosciences Wuhan China

The most important aspect of every civil engineering project is acquiring reliable information on the ground on which the project will be constructed. This research includes a site investigation, which is seen as a primary stage in gathering geological, geotechnical, and other essential engineering data for structures’ safe and cost-effective design. Five boreholes at well-spaced spots were drilled for subsurface investigation at a maximum depth of 15 m to 30 m. The standard penetration tests (SPT) were performed at different depths, soil samples were taken at various intervals, and lithological changes were observed. The friction angle was between 19.6ºand 33.03º, whereas the cohesion ranges between 0.25 kg/cm2 and 0.42 kg/cm2, indicating a strong resistance to shearing and a high capacity to sustain the load. Furthermore, the soil samples’ maximum dry density ranges from 1.63 g/cm3 to 1.80 g/cm3. In addition, water table depths were recorded from 6.0 m to 7.0 m. The net bearing capacity for isolated/pad foundation at a depth of 1.5 m to 2.5 m below the ground level has been calculated as 95.0 to 120.0 kPa and 120.0 to 180.0 kPa for raft foundation. The net allowable pressure settlement limits for isolated/pad and raft foundations are 25 mm (1-inch) and 50 mm (2-inches), respectively. The investigation has found no severe geological flaws on the proposed construction site, and therefore it is appropriate for the construction of an Air Separation Unit (ASU) Oxygen Plant.

关键词： geotechnical properties Subsurface Profile Water Conditions SPT Bearing Capacity Foundation

Quasi-Monte Carlo Simulation-Based SFEM for Slope Reliability Analysis

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Journal of Southwest Jiaotong University(English Edition) 2005年第1期13卷 56-61页

作者：于玉贞谢立全张丙印 Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

Considering the stochastic spatial variation of geotechnical parameters over the slope, a Stochastic Finite Element Method (SFEM) is established based on the combination of the Shear Strength Reduction (SSR) concept and quasi-Monte Carlo simulation. The shear strength reduction FEM is superior to the slice method based on the limit equilibrium theory in many ways, so it will be more powerful to assess the reliability of global slope stability when combined with probability theory. To illustrate the performance of the proposed method, it is applied to an example of simple slope. The results of simulation show that the proposed method is effective to perform the reliability analysis of global slope stability without presupposing a potential slip surface.

关键词： geotechnical properties Shear strength reduction Quasi-Monte Carlo simulation Stochastic finite element method Global slope stability

geotechnical Study of the Aptian Limestone of the Kef Region,Northwestern Tunisia:Evaluation for Industrial Use

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Open Journal of Geology 2018年第12期8卷 1084-1101页

作者： Imed Ben Salah Moufida Ben M’Barek Jemai Safa Mezza Mabrouk Boughdiri Department of Geology Sciences University of BizerteUniversity of CarthageBizerteTunisia

This study aims to the initial characterization of Aptian sedimentary limestones in the Kef region located in the North-West of Tunisia in order to use in industrial fields. The limestone samples were collected from three outcrops respectively named Jebel Jerissa, Jebel Hmeima and Jebel Harraba. A geochemical characterization highlights a variation of the weight percentage (wt%) as follows: CaO (53 - 55), MgO (0.04 - 0.28), Al2O3 (0.07 - 0.51), Fe2O3 (0.41 - 2.87), and a loss on ignition (41.62 - 43.35). The other oxides (K2O, SO3, Na2O) are in trace amounts. Mineralogical analysis revealed that limestones contain more than 95% of calcite and the clay impurities are the minor phases detected. Petrographic study showed that these limestones are packestone-wakestone type. The hardness of Aptian limestones crosses the upper limit of the hard domain. geotechnical tests reveal a Dry Micro Deval (MDS) coefficient varying from 23% to 33%, a Wet Micro Deval (MDH) coefficient with values oscillating around 26% to 36%, a Los Angeles coefficient (LA) about 25% against a value of the compressive strength ranging from 593 Kg/cm2 to 866 Kg/cm2. The gravimetric tests highlighted a flexural strength value from 106 Kg/cm2 at 208 Kg/cm2, while the ultrasonic coefficient oscillates from 4876 m/s to 5233 m/s, indicating the low porosity of these limestone (0.5% to 1%). The density recorded an average value of 2.50 g/cm3. The various properties studied have proved that the limestone studied can be used in various industrial fields such steel industry, aggregate, cement industry and marble.

关键词： Aptian Limestone geotechnical properties Geochemical properties Industrial Use