Concrete made from rapid sulphoaluminate cement is widely used today, especially in China. It is likely to continue gaining popularity since its manufacture produces less CO2 than the process of manufacturing ordinary Portland cement. Elevated temperatures are among the most serious threats to the structural stability of this product. In the present study, laboratory tests were carried out, through

In this work, an improved explosive welding technique was introduced to obtaining high-quality metal coatings, where titanium (TA2) foils with different thicknesses of 0.1, 0.2, 0.3, and 0.4 mm were successfully coated on Q235 steel. Systematic investigations of the achieved claddings were conducted using macro- and micro-morphology observations, EDS elemental analyses, mechanical tests (three-point

The constitutive models of rock are essentially the general depictions of the mechanical responses of rock mass under complex geological environments. Statistical distribution-based constitutive models are of great efficacy in reflecting the rock failure process and the stress–strain relation from the perspective of damage, while most of which were achieved by adopting Drucker–Prager criterion or Mohr–Coulomb

In this work, a novel and practical method is developed to depict the track slab damage and residual strain evolution, where the concrete damage constitutive relation of track slabs is considered within the train–track–bridge dynamics framework. A three-step strain method is presented to judge the load/unloading, compression/tension status of track slab elements ergodically, so that the damage condition

The weldability of the AA2024-T3 and AZ31 Mg alloys was investigated using the modified friction stir clinching-brazing (MFSC-B) and probe-less friction stir spot brazing (PFSSB) processes. A 50 µm thick Zn foil-interlayer was sandwiched between the dissimilar base materials for the welding processes. The mechanical, microstructure, and weld-fracture behaviors of all joints were studied and compared

The proposed study scrutinizes the small scale-dependent geometrical nonlinear flexural response of arbitrary-shaped microplates having variable thickness made of functional graded (FG) composites. Accordingly, the modified couple stress continuum elasticity incorporating the von Karman large deflection supposition is established within a quasi-three dimensional (quasi-3D) plate framework in which

Carbon fiber-reinforced carbon composite (CFC)/Ti6Al4V alloy brazing has been performed with Ag–Cu–Ti braze and Nb (or W) foil. Satisfactory bonding is achieved at the interfaces among substrates, refractory metal layer and fillers. The joining region consists of filler I, refractory metal layer and filler II. The fillers I and II are composed of Ag-based solid solution, TiCu and Cu-based solid solution

In this paper, the results of the analysis of the forces acting on vanes in a double-acting vane pump with an integrated electric drive have been presented. In the new motor pump unit, the pump is assembled inside the rotor of the electric motor. A dynamic model representing the vane movement has been developed considering the impact of pressure load distribution, vane support forces and friction forces

A novel structural system based on precast reinforced concrete (RC) shear wall panels mutually connected vertically using T-connectors and horizontally using friction-bearing devices (FBDs) mounted on interposed steel columns was recently proposed. To investigate the seismic performance of the proposed precast RC shear wall system, three subassembly specimens simulating a single construction modulus

Bilateral deep foundation pit excavation would cause the stress redistribution and large deformation of the adjacent tunnel, and even induce the lining structure cracking. This paper aims to investigate the deformation and stress response of tunnel to bilateral foundation pit construction. The Zhengzhou East High-speed Railway Station (Zhengzhou East HRS) was taken as an example to conduct the analysis

Dual-phase (DP) steel has an excellent blend of various mechanical properties; hence it is used immensely in the automotive industries. It is challenging to form high strength DP steel into desirable complex shapes because of their limited formability at room temperature conditions. One of the proven alternatives is warm/hot forming. In-detail investigation of forming limits over DP590 steel has been

Studies have shown that rubberised concrete is a potential pavement material. Pavement materials are generally expected to possess concrete with high impact resistance, especially in regions where winter temperatures remain lower than the freezing point for long periods. However, knowledge about the performance of rubberised concrete on impact under low temperatures is still limited. In this study

The physically based constitutive modeling, simulation and experimental of a superplastic forming and diffusion bonding (SPF/DB) process were studied for the manufacture of a pyramid lattice Ti-6Al-4 V sandwich panel structure. The high-temperature deformation behaviors of Ti-6Al-4 V were studied using uniaxial tensile tests at various temperatures 860 – 950 °C and strain rates 0.0001 s−1 ~ 0.01 s−1

The precision forming of inner hole is one of technological bottlenecks in Cross-wedge Rolling (CWR) of hollow shaft with mandrel. The inner diameters show signs of characteristic fluctuation despite under the control of mandrel. The uniformity of inner diameter was investigated by finite element simulation and experiments in this study. The inner hole expands at the knifing stage and shrinks at the

The wide range of rivets usage goes back to the processes of manufacturing and repairing an aircraft fuselage. When it comes to structural joints, adhesive bonding is said to have some merits which overshadow other joining methods, such as bolting, riveting, and welding. Today, the applications of structural adhesives do not end in aerospace, but they also are ideal for the automotive industry, where

Chassis frame of electric vehicle contains several thin-walled tube structures that can provide an important component for installing the power unit and supporting the body in white of vehicle. Thus, design a chassis frame is a multi-objective optimization and multi-parameter problem. To address it, the contributions of design variables to the performance indicators of chassis frame are studied first

The effect of the type and content of multi-wall carbon nanotubes (MWCNTs) on the damping performance of cement mortar is studied in this paper. The pristine MWCNTs (P-CNT) and the functionalized MWCNTs (F-CNT) grafted with COOH were used in the experiment. The content of MWCNTs was 0.05wt% and 0.1wt% of cement. The flexural/compressive strength and loss factor of CNT-mortar composites were measured

This paper presents experimental and theoretical investigations on the flexural utilised of FRP (fibre-reinforced polymer) rebar-reinforced ECC (engineered cementitious composite) beams subjected to freeze–thaw cycles. Eight FRP-reinforced specimens after subjected to 0, 50, 100 and 150 cycles of freeze–thaw were tested to failure under flexural loading. Experimental results show that the moment capacity

Rectangular and square hollow steel sections can be manufactured using either a “direct forming” or an “indirect forming” method. The production route for both “direct forming” and “indirect forming” techniques can be conducted at room temperature (cold forming) or elevated temperature (hot forming). It might also start by forming at room temperature and subsequently followed by heat treatment (hot-finishing)

Closed-cell metal foams are cellular solids that show unique properties such as high strength to weight ratio, high energy absorption capacity, and low thermal conductivity. Due to being computation and cost effective, modeling the behavior of closed-cell foams using regular unit cells has attracted a lot of attention in this regard. Recent developments in additive manufacturing techniques which have

This study evaluates the structural performance of reinforced concrete interior beam–column joints having high-strength screw-type steel bars mechanically connected with couplers. A total of six full-scale specimens were cast and subjected to repeated cyclic lateral loads. High-strength screw-type reinforcing bars, with a yield strength of 690 MPa, were used as longitudinal reinforcement of the specimens

In the present investigation, by putting the isogeometric finite element methodology to use, the nonlinear flexural response of composite rectangular microplates having functionally graded (FG) porosity is predicted incorporating couple stress type of small scale effect. To accomplish this analysis, a non-uniform kind of rational B-spline functions are employed for an accurate geometrical description

A new theoretical solution is presented to determine the stress distribution in a ten-layer simply-supported circular composite plate subjected to the low-velocity impact. The aim of the current study is the investigation of the dynamic analysis of the composite plate when a cylindrical impactor hits the top layer of the plate with an initial velocity of 1 m/s. The plate is made of two adhesive layers

The single point incremental forming (SPIF) process is gaining special attention in the aerospace, biomedical and manufacturing industries for making intricate asymmetric components. In the present study, SPIF process has been performed for forming varied wall angle conical and pyramidal frustums using DP590 steel. Initially, the conventional stretch forming process has been performed for finding the

Partially grouted reinforced masonry (PG-RM) shear walls have been widely used as structural elements in low- and medium-rise earthquake-resistant buildings. Nonetheless, assessing its shear strength represents a complex task mainly because the partial grouting provides a non-constant cross section, which results in heterogeneous stress–strain patterns. Consequently, refined modeling techniques are

This study investigated the impact of the equal channel angular pressing (ECAP) combined with heat treatments on the microstructure and mechanical properties of AlSi10Mg alloys fabricated via selective laser melting (SLM) and gravity casting. Special attention was directed towards determining the effect of post-fabrication heat treatments on the microstructural evolution of AlSi10Mg alloy fabricated

The article focuses on the Direct Drive Rotary Friction Welding of ultrafine-grained copper rods, which feature increased mechanical properties and good electrical properties, yet are limited in size. The use of UFG metals is often limited by the too small dimensions of semi-finished elements produced by SPD methods. Therefore, the production of finished machine parts from UFG metals is currently economically

This work investigates the application of three-dimensional nonlocal elasticity theory to elastic static analysis of nanoplates. Unlike all previous papers that considered two-dimensional Laplacian operator to stress components, this work uses the general three-dimensional nonlocal operator with thickness direction operator. The displacement field of nanoplate is assumed a function of three-dimensional

To accurately reproduce the seismic response of the liquefied natural gas (LNG) storage tank equipped with the variable curvature friction pendulum system (VCFPS), a real-time hybrid (RTH) experiment, also known as a real-time substructure experiment, is conducted on it in this study. A typical LNG storage tank with a capacity of 160,000 m3 is employed as the numerical substructure simulated using

Variations in the dynamic triaxial strength of hybrid basalt–polypropylene fibre-reinforced concrete (HBPRC) with strain rate and confining pressure were investigated, and a dynamic non-linear Mohr–Coulomb (M–C) strength criterion for HBPRC was established. The results showed that the dynamic strength of HBPRC increased non-linearly with the strain rate and confining pressure; however, the strain rate

Aluminum alloy 6061-T6 (AA 6061-T6) extrusions have been widely applied in large-span reticulated shells. However, researches on behaviors of the aluminum alloy under large deformation and fracture by means of meso-mechanics are still insufficient. This paper focuses on the plastic and fracture behaviors of AA 6061-T6 extrusions over a wide range of stress states. Experiments on smooth and notched

This article describes the manufacturing of silicon carbide composites with the addition of quasi-two-dimensional titanium carbide Ti3C2, known as MXene. The composites were obtained by the powder metallurgy technique, consolidated with the use of the Spark Plasma Sintering method at 1900 °C and dwelled for 30 min. The influence of the Ti3C2 MXene addition on the microstructure and mechanical properties

The lightweight magnesium–aluminum alloys are extensively used in automotive and aerospace industries due to their high-specific strength and low alloying cost, Grain refining via alloying and hot deformation is known as a viable technique for the enhancement of mechanical properties of these alloys. Accordingly, in the present work, grain size refinement and improvement of tensile properties of Mg-10Al

The main objective of this work is to model wear of a disc which was subjected to dry contact with a ball in unidirectional sliding. Tribological tests of sliding pairs were carried out using a tribological tester T-11 in a ball-on disc configuration. Stationary balls made of 100Cr6 steel with a hardness of 62 ± 2 HRC co-acted with rotating discs with 42CrMo4 steel with a hardness of 40 ± 2HRC. Discs

The mechanical behaviours of microalloyed and low-carbon steels under strain reversal were modelled based on the average dislocation density taking into account its allocation between the cell walls and cell interiors. The proposed model reflects the effects of the dislocations displacement, generation of new dislocations and their annihilation during the metal-forming processes. The back stress is

Steels are the most commonly used multi-phase materials in the industry, and their mechanical behaviors depend on the microstructure, composition, and phase fractions. Generally, the material behaviors need to be measured by experiments like a tensile test or split Hopkinson bar test, which is very time-consuming and expensive. Once the heat treatment and phase fractions are changed, it needs to be

In engineering applications, composite structures supported by elastic foundations are being vastly utilized in various operating environmental conditions. The nonlinear hygrothermal effect on vibration analysis of a magnetostrictive viscoelastic laminated composite sandwich plate rested on two-parameter Pasternak’s foundations is studied in the present article. The material properties of the viscoelastic

This study investigates the activated flux-tungsten inert gas welding (A-TIG) welding of dissimilar P92 steel-304H ASS using ‘wire feed’ (patent pending) in terms of weld pool mixing behavior, microstructure and mechanical properties of the weld joint. ErNiCrMo-3 wire was fed during welding and three-wire feeding configurations were analyzed in view of filler wire melting and weld pool mixing behavior

In this work, multi-wall carbon nanotubes (MWCNT) are added (0–0.5 wt%) into a cement matrix to improve the flexural performance of the resulting nanocomposites. Under static testing, the compressive and flexural strengths were found to increase with MWCNT content with an optimum content of 0.2% and 0.1%, respectively, before decreasing because of dispersion problems (agglomeration). But it was observed

Axisymmetric bending analysis of graphene platelet (GPL) sandwich annular and circular nanoplates with FG porous core and integrated with sensor and actuator resting on an elastic substrate under various boundary conditions is presented in this article. The present nanocomposite model is subjected to mechanical load and an external voltage. The upper and lower sandwich layers are made of aluminum matrix

This paper aims to investigate the feasibility of the incorporation of nanosilica (NS) in ultra-lightweight foamed concrete (ULFC), with an oven-dry density of 350 kg/m3, in regard to its fresh and hardened characteristics. The performance of various dosages of NS, up to 10 wt.-%, were examined. In addition, fly ash and silica fume were used as cement replacing materials, to compare their influence

Pultruded sandwich panel (PSP) usually has light weight, but its flexural performance is limited by the weak shear strength. Filling into expanded polystyrene (EPS) mortar can effectively improve the mechanical properties. The bending performance and failure mode of the EPS mortar-filled PSP were investigated by flexural testing. The ultimate bearing capacity improved from 49.562 kN for unfilled PSP

In this paper, a modified acoustic-plastic Johnson–Cook model for Ti–45Nb alloy was established, which can be used to reveal the metallic deformation behavior under ultrasonic vibration-assisted (TUV) forming. First, the experiments of traditional compression and TUV compression were carried out, the influence of vibration amplitude on yield strength, strain hardening coefficient and index, and strain

In this study, the dynamic, compressive, and flexural behaviors of ultra-rapid-hardening mortar (URHM) containing 2% polyethylene fiber are investigated. The results confirm the robust strain-hardening behavior of URHM at an early age of 4 h. Its tensile strength, strain capacity, and g value at 4 h were found to be 7.3 MPa, 5.1%, and 297.5 kJ/m3, respectively. The compressive and flexural strength

Failure in sheet metal forming can occur by necking, fracture or wrinkling. By using a forming limit diagram (FLD) as a powerful tool to prevent sheets metal failures in the forming process, provides parameters controlling throughout forming. There are different developed methods for predicting FLDs, which estimate sheet metal forming strains limits. Assessment of FLD estimation reveals that there

The concrete-filled steel tube (CFT) composite frames using blind bolts and buckling-restrained braces (BRBs) have been studied with the development of building industrialization and energy dissipation technology. However, there has been no research so far on the probabilistic seismic fragility analysis for the blind-bolted end-plate CFT composite frames with BRBs (BRB-BECFT). Therefore, a total of

Results of a study investigating a skew rolling process for elongated axisymmetric parts are presented. Despite the fact that the skew rolling technique for producing such parts was developed and implemented in the mid-twentieth century, there are no studies on this problem. The first part of this paper presents the results of FEM modelling of skew rolling stepped axles and shafts (solid and hollow)

To study the damage characteristics of rock mass under multi-level creep load, damage variable D was defined based on the spatio-temporal evolution characteristics of deformation modulus E, and the Kachanov damage theory is used to describe the damage evolution, then the damage evolution equation of the rock mass under multi-level creep load is obtained. Combining the damage evolution equation with

In this study, dual-phase (DP, ferrite + martensite) microstructures were obtained by performing intercritical heat treatments (IHT) at 750 and 800 °C followed by quenching. Decreasing the IHT temperature from 800 to 750 °C leads to: (i) a decrease in the volume fraction of austenite (martensite after quenching) from 0.68 to 0.36; (ii) ~ 100 °C decrease in martensite start temperature (Ms), mainly

In this paper, a unified viscoplastic constitutive model for Ti–6Al–4V alloy coupling with damage and softening mechanisms was established to predict the flow behaviors and damage evolution in hot tensile process. To obtain the flow behaviors of Ti–6Al–4V alloy, the hot tensile tests were performed at temperatures between 750 °C and 850 °C and strain rates of 0.01–1 s−1. Then the evolution of microstructure

This paper investigated the relationship between the strength of fractured rock and the crack propagation process. A series of uniaxial compression tests were carried out on the rock-like material specimens with single pre-fabricated flaw. Moreover, DIC (digital image correlation) technology was utilized to monitor and analyze the failure process of specimens. The initiation of each crack was defined

The article presents the profit optimization model for multi-unit construction projects. Such projects constitute a special case of repetitive projects and are common in residential, commercial, and industrial construction projects. Due to the specific character of construction works, schedules of such projects should take into account many different aspects, including durations and costs of construction

When a metro is constructed by the shield method in the strata containing boulder group, it is prone to some engineering problems such as serious cutter wear, deformation of the cutter holder head, damage of the cutter spindle, which seriously affects the construction efficiency and bring enormous problems to the shield construction. This paper proposes the vibration reduction measures for the boulder

Recent research in engineering seismology demonstrated that in addition to three translational seismic excitations along x, y and z axes, one should also consider rotational components about these axes when calculating design seismic loads for structures. The objective of this paper is to present the results of a seismic response numerical analysis of a mine tower (also called in the literature a headframe

Burzynski criterion is a well-known criterion is employed for pressure-sensitive isotropic materials. In the current study, this criterion is modified for asymmetric anisotropic materials called hear MB. Firstly, a modified deviatoric stress tensor is defined with a linear transformation to consider the anisotropy effects of materials. Secondly, MB is presented by the sum of n-components to have more

This paper reports on a comprehensive research on the performance of self-centering masonry walls (SMWs). A summary of an experimental study is presented. Finite element (FE) study was performed and verified against experimental results to predict the behaviour of SMWs. Using the verified FE modelling; Phase I of a parametric study was conducted aiming at developing a refined approach to better predict

The development of an efficient numerical approach for the generation of a wide range of heterogeneous microstructures models with the application of the lean workflow concept is presented in the paper. First, the idea and implementation details of the developed cellular automata-based computational library allowing the development of digital material representation models within a workflow are presented

The warm roll bonding technique was adopted to fabricate Aluminum–polyurethane–Aluminum (Al–PU–Al) composites. Glass whiskers or SiC particles were added to reinforce the inner layer. The main objective of the present study is to examine experimentally the main manufacturing parameters, including interface properties and layer thicknesses, both of which control the strength and integrity of Al–PU–Al