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Journal of Rock Mechanics and Geotechnical engineering 2020年第1期12卷 180-187页

作者： Aswin Lim Petra Cahaya Atmaja Siska Rustiani department of civil engineering Universitas Katolik ParahyanganBandung40141Indonesia

This article presents an innovative method of bio-mediated soil improvement for increasing the shear strength of loose *** improvement is realized by mixing the loose sand with the inoculum of Rhizopus oligosporus,a kind of fungus widely used in food industry for making Indonesian *** objective of this article is to investigate the performance and mechanism of mixing tempeh inoculum as a binding agent of loose sand *** inoculum dosage,water content of loose sand,and curing time were examined for identifying the increment of unconfined compressive strength(q_u)of the *** results showed that q_u of the treated samples increased when the inoculum dosage was *** shows that 5.24%inoculum could yield 68 kPa of q_u,and 5%water content and 3 d curing time produced the maximum q_***,the mechanism of hypha and mycelium in binding the soil particles was clearly observed using a digital microscope and scanning electron microscope.

关键词： Bio-mediated soil improvement Loose sand Rhizopus oligosporus

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Effect of interlayer cold joint on mechanical properties and permeability of roller compacted concrete

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Frontiers of Structural and civil engineering 2025年第2期19卷 284-299页

作者： Sultan Husein BAYQRA SüleymanÖZEN Ali MARDANI Kambiz RAMYAR department of civil engineering Faculty of EngineeringBursa Uludag UniversityNilüfer 16059Turkey department of civil engineering Faculty of Engineering and Natural SciencesBursa Technical UniversityYildirim 16330Turkey department of civil engineering Faculty of EngineeringEge UniversityBornova 35100Turkey

One issue with layer application of roller compacted concrete(RCC)is the development of cold joints,which can cause damage to RCC *** this study,fly ash was used in place of 0%,20%,40%,and 60%of the cement or aggregate to examine the impact of interlayer cold joint formation on RCC *** promote cold joint formation,the second layer was placed and compacted with a delay of 0,60,120,or 180 min after the first *** methods were tried for preventing cold joints from forming:one was to apply a bedding mortar to the interlayer,another was to add a set retarder admixture,and the third was to spray an adhesion-enhancing chemical additive on the surface of the first *** on the 28 d specimens’compressive and splitting-tensile strengths as well as the depth of water penetration under pressure,the most effective method was found to be applying interlayer bedding *** 180 min delayed layer castings,the splitting-tensile and compressive strengths of the control samples decreased by 31%and 17%,respectively,while the strengths of mixtures applying interlayer bedding mortar decreased by 9%and 10%.In addition,bedding mortar treatment decreased the water permeability by 59%compared to the *** cold joint decreased all mixtures’moduli of elasticity,regardless of the age of the *** the interlayer delay was 60 min,the modulus of elasticity decreased by 1%–4%.It was between 2%and 14%,and between 10%and 24%at 120 and 180 min for the interlayer *** longer the delay in placing the second RCC layer,the more detrimental the effect of the cold *** effect was most noticeable on mechanical and permeability properties tested with applied load or water pressure parallel to the cold joint,such as flexural and splitting tensile strengths and water penetration depth under pressure.

关键词： roller compacted concrete cold joint mechanical properties permeability properties fly ash

Undrained bearing capacity of obliquely-eccentrically loaded shallow foundations overlying a heterogeneous and inherently anisotropic clay deposit

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Journal of Rock Mechanics and Geotechnical engineering 2025年第1期17卷 586-613页

作者： Maedeh Nasiri Pishvari Hessam Fathipour Suraparb Keawsawasvong Boonchai Ukritchon Meghdad Payan Reza Jamshidi Chenari department of civil engineering Faculty of EngineeringUniversity of GuilanRashtIran Research Unit in Sciences and Innovative Technologies for civil engineering Infrastructures Department of Civil EngineeringThammasat School of EngineeringThammasat UniversityThailand department of civil engineering.Chulalongkorn University BangkokThailand department of civil engineering GeoEngineering Centre at Queen's RMCRoyal Military College of CanadaKingstonCanada

Clay deposits typically exhibit significant degrees of heterogeneity and anisotropy in their strength and stiffness *** non-monotonic responses can significantly impact the stability analysis and design of overlying shallow *** this study,the undrained bearing capacity of shallow foundations resting on inhomogeneous and anisotropic clay layers subjected to oblique-eccentric combined loading is investigated through a comprehensive series of finite element limit analysis(FELA)based on the well-established lower-bound theorem and second-order cone programming(SOCP).The heterogeneity of normally consolidated(NC)clays is simulated by adopting a well-known general model of undrained shear strength increasing linearly with *** contrast,for overconsolidated(OC)clays,the variation of undrained shear strength with depth is considered to follow a bilinear ***,the inherent anisotropy is accounted for by adopting different values of undrained shear strength along different directions within the soil medium,employing an iterative-based *** results of numerical simulations are utilized to investigate the influences of natural soil heterogeneity and inherent anisotropy on the ultimate bearing capacity,failure envelope,and failure mechanism of shallow foundations subjected to the various combinations of vertical-horizontal(V-H)and vertical-moment(V-M)loads.

关键词： Shallow foundation Bearing capacity Combined loading Undrained shear strength Inherent anisotropy Heterogeneity

An assessment of atmospheric concentrations and spatiotemporal variation of BTEX and associated pollutants in India

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Journal of Environmental Sciences 2025年第4期150卷 230-245页

作者： Sruthi Jayaraj S.M.Shiva Nagendra department of civil engineering Indian Institute of TechnologyChennai 600036India

Benzene,toluene,ethylbenzene,and xylene(BTEX)pollution poses a serious threat to public health and the environment because of its respiratory and neurological effects,carcinogenic properties,and adverse effects on air *** exposure is a matter of grave concern in India owing to the growing vehicular and development activities,necessitating the assessment of atmospheric concentrations and their spatial *** paper presents a comprehensive assessment of ambient concentrations and spatiotemporal variations of BTEX in *** study investigates the correlation of BTEX with other criteria pollutants andmeteorological parameters,aiming to identify interrelationships and diagnostic indicators for the source characterization of BTEX ***,the paper categorizes various regions in India according to the Air Quality Index(AQI)based on BTEX pollution *** results reveal that the northern zone of India exhibits the highest levels of BTEX pollution compared to central,eastern,and western *** contrast,the southern zone experiences the least pollution with *** analysis indicates that winter and postmonsoon periods,characterized by lower temperatures,are associated with higher BTEX levels due to the accumulation of localized *** comparing the different zones in India,high traffic emissions and localized activities,such as solvent use and solvent evaporation,are found to be the primary sources of *** findings of the current study aid in source characterization and identification,and better understanding of the region’s air quality problems,which helps in the development of focused BTEX pollution reduction and control strategies.

关键词： VOCs BTEX India AQI Spatiotemporal variation

Bi-directional interaction of joint shear strength in non-seismically designed corner RC beam-column connections under seismic loading

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Earthquake engineering and engineering Vibration 2025年第1期24卷 135-153页

作者： Mohammad Amir Najafgholipour Negin Ahmadi rad Akanshu Sharma department of civil and Environmental engineering Shiraz University of TechnologyShiraz ***Iran Lyles School of civil engineering Purdue UniversityWest LafayetteIN 47907-2050USA

Non-seismically designed(NSD)beam-column joints are susceptible to joint shear failure under seismic *** significant research is available on the seismic behavior of such joints of planar frames,the information on the seismic behavior of joints of space frames(3D joints)is *** 3D joints are subjected to bi-directional excitation,which results in an interaction between the shear strength obtained for the joint in the two orthogonal directions *** bi-directional seismic behavior of corner reinforced concrete(RC)joints is the focus of this ***,a detailed finite element(FE)model using the FE software Abaqus,is developed and validated using the test results from the *** validated modeling procedure is used to conduct a parametric study to investigate the influence of different parameters such as concrete strength,dimensions of main and transverse beams framing into the joint,presence or absence of a slab,axial load ratio and loading direction on the seismic behavior of *** subjecting the models to different combinations of loads on the beams along perpendicular directions,the interaction of the joint shear strength in two orthogonal directions is *** comparison of the interaction curves of the joints obtained from the numerical study with a quadratic(circular)interaction curve indicates that in a majority of cases,the quadratic interaction model can represent the strength interaction diagrams of RC beam to column connections with governing joint shear failure reasonably well.

关键词： beam-column joints joint shear failure bidirectional loading interaction curve finite element study

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Dynamic modeling of minimum mass of pore-gas for triggering landslide in stable gentle soil slope

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Journal of Rock Mechanics and Geotechnical engineering 2025年第2期17卷 652-670页

作者： Xingyu Kang Zhongqi Quentin Yue department of civil engineering The University of Hong KongHong KongChina

This paper presents a dynamic modeling method to test and examine the minimum mass of pressurized pore-gas for triggering landslides in stable gentle soil slopes.A stable gentle soil slope model is constructed with a dry cement powder core,a saturated clay middle layer,and a dry sand upper *** test injects H_(2)O_(2)solution into the cement core to produce new *** model test includes three identical H_(2)O_(2)*** small mass of generated oxygen gas(0.07%of slope soil mass and landslide body)from the first injection can build sufficient pore-gas pressure to cause soil upheaval and ***,despite the first injection causing leak paths in the clay layer,the generated small mass of gas from the second and third injections can further trigger the landslide.A dynamic theoretical analysis of the slope failure is carried out and the required minimum pore-gas pressure for the landslide is *** mass and pressure of generated gas in the model test are also estimated based on the calibration test for oxygen generation from H_(2)O_(2)solution in cement *** results indicate that the minimum mass of the generated gas for triggering the landslide is 2 ppm to 0.07%of the landslide ***,the small mass of gas can provide sufficient pressure to cause soil upheaval and soil sliding in dynamic analysis.

关键词： Landslide Gentle soil slope Physical model test Minimum pore-gas mass Soil upheaval Dynamic modeling

Analysis of Nuclear Structure Properties and Stellar β-decay Rates of Even–Even 106–120Zr Isotopes

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Research in Astronomy and Astrophysics 2025年第1期25卷 162-174页

作者： Abdul Kabir Jameel-Un Nabi Syeda Anmol Rida Izzah Anwaar Noor-Ul Ain Raza Hamad Almujibah department of Space Science Institute of Space Technology University of Wah department of civil engineering College of EngineeringTaif University

The nuclear ground state properties of even–even106–120Zr nuclei have been investigated within the framework of the relativistic mean field （RMF） *** RMF model with density-dependent DDME2 and DDPC1interactions is utilized for the calculation of potential energy curves,the nuclear ground-state deformation parameters （β2）,neutron separation energies (S_nand S2n) and neutron skin thickness (rnp) of selected Zr ***,the β-decay properties of Zr isotopes were studied using the proton-neutron quasi-particle random phase approximation （pn-QRPA） *** include Gamow–Teller strength distributions,β-decay half-lives and stellar electron emission/positron capture *** β2values computed from the RMF model were employed in the pn-QRPA model as an input parameter for the calculations of β-decay properties for even–even106–120Zr *** stellar rates were computed using the pn-QRPA framework with three different types of deformation *** at high temperature （T9≥2） and low density (ρYe≤10～7g cm-3) values,the sum of electron emission and positron capture rates has a sizeable contribution （with positive exponents） to the stellar rates.

关键词： (stars:) supernovae: individual (r-process) abundances astroparticle physics elementary particles nuclear reactions nucleosynthesis

Effects of spatial heterogeneity on pseudo-static stability of coal mine overburden dump slope,using random limit equilibrium and random finite element methods:A comparative study

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Earthquake engineering and engineering Vibration 2025年第1期24卷 83-99页

作者： Madhumita Mohanty Rajib Sarkar Sarat Kumar Das department of civil engineering Indian Institute of Technology(ISM)DhanbadDhanbad 826004India

Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of *** of the spatial heterogeneity of OB dump materials is imperative for an adequate evaluation of the seismic stability of OB dump *** this study,pseudo-static seismic stability analyses are carried out for an OB dump slope by considering the material parameters obtained from an insitu field *** heterogeneity is simulated through use of the random finite element method(RFEM)and the random limit equilibrium method(RLEM)and a comparative study is *** of horizontal and vertical spatial correlation lengths were considered for simulating isotropic and anisotropic random fields within the OB dump *** performances of the slope have been reported through the probability of failure and reliability *** was observed that the RLEM approach overestimates failure probability(P_(f))by considering seismic stability with spatial *** P_(f)was observed to increase with an increase in the coefficient of variation of friction angle of the dump ***,it was inferred that the RLEM approach may not be adequately applicable for assessing the seismic stability of an OB dump slope for a horizontal seismic coefficient that is more than or equal to 0.1.

关键词： coal mine overburden dump slope random limit equilibrium method random finite element method seismic slope stability spatial heterogeneity

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Topology, Size, and Shape Optimization in civil engineering Structures: A Review

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Computer Modeling in engineering & Sciences 2025年第2期142卷 933-971页

作者： Ahmed Manguri Hogr Hassan Najmadeen Saeed Robert Jankowski Faculty of civil and Environmental engineering Gdansk University of TechnologyGdansk80-223Poland department of Computer Science ModelingElectronics and Systems EngineeringUniversity of CalabriaCosenza87036Italy civil engineering department University of RaparinRania46012Iraq civil engineering department Tishk International UniversityErbil44001Iraq

The optimization of civil engineering structures is critical for enhancing structural performance and material efficiency in engineering *** optimization approaches seek to determine the optimal design,by considering material performance,cost,and structural *** design approaches aim to reduce the built environment’s energy use and carbon *** comprehensive review examines optimization techniques,including size,shape,topology,and multi-objective approaches,by integrating these *** trends and advancements that contribute to developing more efficient,cost-effective,and reliable structural designs were *** review also discusses emerging technologies,such as machine learning applications with different optimization *** of truss,frame,tensegrity,reinforced concrete,origami,pantographic,and adaptive structures are covered and *** techniques are explained,including metaheuristics,genetic algorithm,particle swarm,ant-colony,harmony search algorithm,and their applications with mentioned structure *** and non-linear structures,including geometric and material nonlinearity,are *** role of optimization in active structures,structural design,seismic design,form-finding,and structural control is taken into account,and the most recent techniques and advancements are mentioned.

关键词： Structural optimization topology optimization size optimization shape optimization multi-objective optimization

Predicting the strength of fiber reinforced polymer materials externally bonded to masonry using artificial intelligent techniques

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Frontiers of Structural and civil engineering 2025年第2期19卷 242-261页

作者： Khalid Saqer ALOTAIBI department of civil and Construction engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityDammam 31451Saudi Arabia

Fiber reinforced polymer(FRP)retrofits are widely used to strengthen structures due to their advantages such as high strength-to-weight ratio and ***,the bond strength between FRP and masonry is crucial for the success of these *** data exists on the shear bond between FRP composites and masonry substrates,necessitating the development of accurate prediction *** study aimed to create machine learning models based on 1583 tests from 56 different experiments on FRP-masonry bond *** researchers identified key factors influencing failure load and developed machine learning models using three *** proposed models outperformed an existing model with up to 97%accuracy in predicting shear bond *** findings have significant implications for designing safer and more effective FRP retrofits in masonry *** study also used Sobol sensitivity analysis and SHapley Additive exPlanations(SHAP)analysis to understand the machine learning models,identifying key input features and their importance in driving *** enhances model transparency and reliability for practical use.

关键词： fiber reinforced polymer retrofits bond strength masonry substrate shear pull out tests machine learning model