Calcareous sand fractures easily, has poor mechanical properties, and usually needs to be stabilized for engineering applications using additives. In this study, nano-MgO was used enhance the properties of cement-stabilized calcareous (CCS). Unconfined compressive strength (UCS) unconsolidated undrained (UU) triaxial shear tests were conducted on nano-MgO-modified CCS (MCCS) specimens, microscopic mechanism investigated scanning electron microscopy X-ray diffraction. Finally, models predict...

Biomass chars (bio-chars) prepared under two pyrolysis modes and with four particle size ranges were investigated. The included isothermal non-isothermal three heating rates (5 °C/min, 10 15 °C/min). 58-75 μm, 75-106 106-150 150-270 μm. characteristics, pore structures, surface morphologies, functional groups of the bio-chars characterized by TGA, specific area porosity analyses, SEM, FTIR. mercury adsorption was further explored kinetics. results established optimum conditions for...

Abstract How to more effectively and comprehensively utilize recycled aggregate resources prepare a richer new low-carbon concrete material system is the key path achieve development in China’s construction field. Based on properties of graphite tailings (GT), this article explores organic combination GT replace sand aggregates (RA) natural stones, order propose an efficient recycling for multiple solid wastes cost-effective (RAC). This focuses investigating influences (0–40%) RA...

Bark is one of the most under-utilized types lignocellulosic biomass in forest industry. In this study, bark fast pyrolysis was optimized for phenols yield using response surface methodology (RSM), considering temperature, gas flow rate, and particle size. The bio-oil generated under optimal conditions then characterized by chromatography-mass spectrometry (GC-MS), ultimate analysis, several physical methods. A regression equation estimated based on statistical analysis. It found that were...

Hybrid electric vehicle (HEV) is one of the ideal transportation tools to face challenge 'Carbon peak carbon neutralization'. The high complexity latest HEVs result difficulties in fault diagnostics, which considered be main factors durability. In this study, a multi-fault mode detection method P2 diesel HEV was investigated by using support vector machine(SVM). physical model built and validated experimental data under China typical urban driving cycle (CTUDC). SVM algorithm coded...

This paper investigated the mechanical and electroconductivity properties of graphite tailings concrete, in which are replaced as sand. The results showed that concentration has an important influence on mechanical, electroconductivity, material concrete. Finally, a new model for calculating relationship between compressive strength electrical resistivity based grey correlation method was obtained providing theoretical basis building green intelligent materials.

In order to solve the limitation of graphite tailings in improving toughness cement-based materials, this paper aims study effect basalt fibres (BF) on mechanical properties cement mortar (GTCM). Basic physical and tests such as fluidity, water absorption, surface content, flexural strength, compressive strength modulus elasticity were conducted fibre-reinforced (BFR-GTCM), combined with microscopic scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared...

This paper presents an experimental investigation of flexural behavior circular ultra-high-performance concrete with coarse aggregate (CA-UHPC)-filled steel tubes (CA-UHPCFSTs). A total seven members were tested under a four-point bending load. The failure modes, overall deflection curves, moment-versus-curvature relationships, moment-versus-strain strain distribution ductility, stiffness and ultimate capacity evaluated. results indicate that the CA-UHPCFSTs behaved in good ductile manner....

This research investigates the effects of iron tailings content on mechanical properties and durability concrete under dry–wet cycling negative temperature conditions (−10 °C), where replace river sand at rates 0%, 10%, 20%, 30%. A variety tests were conducted concrete, including compressive strength, flexural splitting tensile mass loss, relative dynamic modulus, its pore characteristics analyzed using low-field nuclear magnetic resonance (NMR) experiments. The results reveal that when 20%...

The second invariant of deviatoric stress the coal and rock mass is closely related to distortion energy driving deformation failure surrounding rock. Based on stress, this study built a global model gob-side entry with different widths pillar through numerical analysis, compared analyzed evolution law energy, plastic location state, roadway width pillar. This concluded that peak in virgin rib roof floor gradually increases reduction width. When 5 m, value reaches maximum 294.8 MPa2. reduced...

This research investigates the influence of water-cement ratio and recycled aggregate content on chlorine erosion resistance RAC by conducting a combination experimental theoretical analysis. In addition, mathematical equation is developed to represent chloride ion transport mechanism in RAC, taking into account fluid mechanics, energy conservation, pore structure evolution characteristics. Furthermore, analysis modeling are used forecast life process. The results show that both coarse...

Current research focuses on how graphene oxide (GO) promotes the hydration reaction of fly ash-slag based geopolymer (FASG) and optimizes its pore structure, while there are fewer studies interactions between GO C-A-S-H molecules. In this research, we first analysed reduction reactions that occur during dispersion into alkali exciters, also explored adsorption Ca2+ by reduced (RGO) (since is an important constituent gels). Subsequently, addressed effect RGO substitution mode Al-O tetrahedra...

This paper adopts the method of steel tube wall thickness and strength reduction to simulate corrosion damage. The numerical model square concrete-filled long column (SCFST-LC) under eccentric compression after acid rain is established in finite element software, ABAQUS. reliability accuracy are verified by comparing it with published relevant experimental results. failure mode, load-deformation curve, ultimate compressive load were analysed. Following that, impacts section size, yield tube,...