In this study, a three-dimensional model of a concrete pump truck conveying pipe was established, and a computational fluid dynamics-discrete element method (CFD-DEM) coupling model was used to simulate the pumping process of fresh concrete in different pipes. The influences of the structural parameters and inclination angles of the taper pipe, bend pipe, and their combination on the pressure loss

Large amounts of nonrenewable resources are depleted by the construction industry in addition to the generation of million tons of mineral waste and carbon dioxide gas every year. For the sake of a more sustainable consumption pattern of building materials, as well as for reducing the waste flux to landfills, the use of recycled materials and wastes should be researched and motivated. In this sense

The hydration rate, microstructure, mechanical properties and durability of Magnesium phosphate cement (MPC) prepared by different kinds of phosphates are quite different. These differences in macroscopic properties are essentially determined by microscopic chemical reactions. Therefore, in this paper, the adsorption mechanism of MgO interface to water and ions in the initial hydration process of MPC

The adhesive and cohesive properties of asphalt, mastic, and mortar in the same porous asphalt (PA) mixture essentially control the durability and failure mechanism of PA mixtures. A typical PA mixture with three types of asphalt was investigated, and the corresponding asphalt, mastic, and mortar were also designed. Binder bond strength (BBS) test was used to evaluate the adhesion and cohesion (Ad/Co)

The construction season is limited in northern countries due to the severe cold weather conditions and their detrimental impacts on concrete quality. Thus, there are excessive expenses required annually for insulation and energy-intensive heating systems for cold-weather concreting. This experimental study aimed to investigate the potential of using high-strength one-part alkali-activated blast furnace

This paper studies the effects that varying amounts of waste cooking oil (WCO) and waste engine oil (WEO) have on the rejuvenation effect of aged asphalt, and the road performance of the 7% compound regenerant to different contents of RAP. The basic performance tests demonstrated the regeneration effect of waste oil, while the microscopic test and chemical composition analysis revealed the regeneration

In order to study the nonlinear creep mechanism of concrete materials, predict and evaluate the safety of the structure, uniaxial nonlinear creep tests of concrete specimens under different ages and stress-strength ratios (σ/fc) were carried out. Based on the discrete element theory (DEM), a concrete three-phase numerical simulation model is established, which considers the real aggregate shape and

This study deals with using a neural network in generalized Group Method of Data Handling (GMDH) type successfully to model and predict the standard cube strength of SFRRCAC (steel fiber reinforced recycled coarse aggregate concrete) based on the data obtained experimentally through point-load test (PLT) and ultrasonic pulse velocity (UPV) approaches. Two methods of singular value decomposition (SVD)

This paper presents the results of an investigation into the use of newly developed thermoplastic-based glass fiber-reinforced polymer (GFRP) bars as reinforcement in concrete structures. GFRP bars made with thermoplastic resins have an advantage over thermosetting-based ones in that they can be shaped after initial production of a straight profile, similar to conventional steel bars. In addition,

Enhancing the properties of concrete using C-S-H seed has been a challenging task due to its agglomeration in the cement matrix. Here, for ensuring synthetic C-S-H disperse well in the cement matrix, it was first synthesized in situ on fly ash (FA) by co-precipitation method, and the C-S-H grown in situ on FA (C-S-H@FA) was received. And then, its phase composition, morphology and particle size distribution

Determination of fracture toughness (KIc) for the asphalt mixture concrete requires employment of suitable testing methods and specimens. Disc-shape specimens are among the favorite test geometries for conducting the fracture toughness experiments on asphalt concrete materials since they can be manufactured easily from those samples obtained by the gyratory compactor machine. Semi-circular bend (SCB)

A comprehensive experimental campaign was carried out to assess the flexural fatigue behaviour of an ultra-high-performance fibre-reinforced concrete. Several concrete mixes were submitted to room temperature, 100 °C, 200 °C, and 300 °C. Two types of reinforcement were explored: steel fibres and a combination of steel and polypropylene fibres. The influence of the addition of fibres and the temperatures

Using plant residues in building materials may reduce both short and long-term effects on the environment. In this paper, we used potato peel powder (PPP) to investigate the effects of this residue on sound insulation and other physicochemical properties. To achieve the optimal properties of the bricks, we utilized three percentages of dried PPP. We dried bricks and then fired them in the kiln at 1000 °C

Use of lime as construction material is limited mainly by low initial strength. These properties can be improved by adding pozzolanic materials, but the evolution of the reaction usually needs older ages than 7 days. Alkali-activated materials, or geopolymers, are good-performance materials that can be produced with residual waste. The combination of traditional and new materials can lead to new uses

In urban environments, the durability of reinforced concrete structures is limited by carbonation-induced corrosion. To prevent steel corrosion, the selection of a proper concrete in terms of type of binder, water/binder ratio and curing time, is of fundamental importance. At this aim the knowledge of the resistance to carbonation in the exposure environment is required. Usually carbonation is evaluated

To fully understand the fracture behaviour of concrete after low-cycle reciprocating loading, a series of experiments are carried out using compact tension specimens. An improved wedge splitting device for adaptive loading is proposed to relieve the brittle unloading process during the concrete fracture tests. Due to the additional springs, the complete stress–strain curves representing concrete fracture

Fatigue failure of the cement-treated base (CTB) is always paid more attention by highway constructors. Meso-scale cracking evolution plays an essential role in the research of fatigue deterioration mechanism, which is hard to be characterized using experimental techniques alone. The objective of this paper is to investigate the fatigue behaviour of CTB materials under cyclic loading through the discrete

In this study, a full-scale model of a railway track structure using an asphalt concrete trackbed with concrete slab panel (ACTSP) is developed. Slab panels are very important to develop asphalt concrete (AC) track system for minimizing the roadbed pressure due to the trainload and reducing the plastic deformation of the AC. The purpose of this study is to analyze the performance of the subgrade and

The conventional bitumen, which is very sensitive to temperature, used in roads construction has very low thermal conductivity due to which heat absorbed is accumulated within it and a very less fraction of it is dissipated. Nanotechnology was introduced to overcome this issue where bitumen was modified by several metallic oxide powders at nanoscale. Nano-TiO2, nano-ZnO and nano-Al2O3 were mixed with

Focusing on the fundamental issue of the bond performance of steel fiber in cementitious matrix of concrete, a multi-index synthetical evaluation was carried out to link the bond mechanisms to the features of complete load-slip curve of hooked-end steel fiber under a pull-out test. The features of curve at ascending portion, peak and descending portion of hooked-end steel fiber embedded in mortar were

The development of microstructure of cement-based materials should be mainly responsible for the time dependences of their rheological properties. In this paper, a series of structural kinetics constitutive models were established to predict the time-evolutions of the rheological properties of fresh cement paste under different working conditions. The models were developed from the Hershel-Bulkley

Curved concrete bridges with small radii and large longitudinal slopes are important parts of viaduct ramp, on which the asphalt pavement plays an important role in resisting and dispersing traffic loads. Due to the complexity of curved concrete bridge structures with small radii and large longitudinal slopes, the asphalt pavement is subjected to complex mechanical action under loading. This study

Using sea sand instead of river sand and recycled coarse aggregates instead of natural coarse aggregates to prepare sea sand and recycled aggregate concrete (SSRAC) can help preserve sand and stone resources, reduce construction costs, and protect ecological environments. However, the chloride ions in sea sand corrode steel bars, posing a safety risk to concrete structures. Fibre-reinforced polymer

This study aims to determine the contribution of fly ash to the compressive strength development of mortars cured at different temperatures based on the cementing efficiency factor. The strength development of mortar specimens with different fly ash replacement ratios cured at 10 °C, 20 °C, and 30 °C was analyzed considering the apparent activation energy. Subsequently, the contribution of fly ash

To increase the utilization rate of supplementary cementitious materials (SCMs), the filler effect and activity effect of low-calcium fly ash (LFA) and ground granulated blast furnace slag (GGBFS) on the early hydration of blended cement were analyzed based on calorimetric test. The test results showed that the full-width at half-maximum (FWHM) value of exothermic peak from calorimetric test could

In this study, we investigate the potential use of the material excavated by tunnel boring machines (TBMs) as structural concrete aggregate. Accordingly, several experimental and statistical investigations on the mechanically and thermally processed material were carried out. The raw TBM excavated material contained a considerable amount of macro–micro quartz sand. Additionally, the poor-grain size

Geopolymer binders have attracted considerable attention in experimental research, in which their formation mechanism, molecular structure types, and the evolution of their amorphous products have been identified to a wide extent. However, significant challenges and barriers were found in the numerical modeling of such kind of materials. This paper reviews the recently released molecular dynamics (MD)

Geopolymers (inorganic polymers) were developed and patented by Joseph Davidovits in the 1970’s and have gained significant attention in the civil construction industry. Since then, the properties of geopolymers have been studied by many researchers, such as their use as a repair material on reinforced concrete structures. Thus, this study aimed to evaluate the mechanical properties of metakaolin-based

This study evaluates the effects of post-compaction wetting–drying (WD) process, freeze–thaw (FT) cycles and cement content (CC) on the microstructure, volumetric strain (εv), soil–water characteristic curve (SWCC), resilient modulus (MR), unconfined compressive strength (qu), and reloading modulus (E1%) and axial stress (Su1%) at 1% strain level of a cement-stabilized expansive soil. The specimens

Increasing the amount of final hydration products of magnesium potassium phosphate cements (MKPC) can improve its mechanical properties and increase its application diversity. This work investigates the influence of the MgKPO4·6H2O (K-struvite) on the hydration behavior and mechanisms of MKPC with Mg/P ratio of 6 at w/c ratio of 0.3. The results indicate the number of exothermic peaks decreases with

The clay block structural masonry is the most common building system in Brazil, being used even in buildings with ten or more floors. Sometimes, when the buildings are already in use and the total load is fully completed, the dwellings users need to change hydraulic, gas or electrical installation position in masonry walls, cutting the structural elements. This is the most critical problem for building

The variation of water content significantly affects the strength development of stabilized dredged sludge (DS), as well as the rational use of binder. This paper experimentally studies the strength and microstructure evolutions of DS stabilized with alkali-activated ground granulated blast-furnace slag (GGBS) under different water contents, via a range of unconfined compressive strength (UCS), X-ray

In the present work, chopped carbon fibers (CFs) were incorporated into a CF-reinforced cementitious matrix (C-FRCM) and are considered to be an operative reinforcement material with a good compatibility with concrete. The interfacial bonding between the C-FRCM and concrete was evaluated by pull-off and double-shear tests. The pull-off and shear strengths of the C-FRCM with chopped CFs were enhanced

The resilient modulus (MR) of road materials is one of the most important parameters in the analysis and design of pavement. This parameter is used in both empirical methods and mechanistic-empirical methods as the main parameter for expressing the stiffness and behavior of road construction materials. To determine this parameter in the laboratory, it is necessary to perform a dynamic tri-axial loading

Sustainable infrastructure materials are always correlated with the innovative and value-added disposal of solid waste. This study investigates the production of cement-free controlled low strength material (CLSM) depending on the pozzolanic reaction between waste glass powder (GP) and hydrated lime (CH). CLSM mixtures with varying GP/CH ratios were characterized by flow consistency, mechanical properties

This paper describes an experimental study, which has been lacking to date, into the mechanical properties of cementitious composites incorporating granules and fibres from recycled Reinforced PVC (RPVC) banners. A detailed account of over 140 tests on cylindrical, cubic and prismatic samples tested in compression and flexure, with up to 20% replacement of mineral aggregates, is given. Based on the

There is an ongoing concern about premature cracking of concrete bridge decks. Bridge deck cracking reduces the service life of bridges and results in increased maintenance and replacement costs. Ideally, a deck should last as long as the support structure with minimal maintenance. However, bridge decks typically need to be replaced two or more times before the structure needs to be replaced. Such

This paper aims to explore the potential use of flue gas desulfurisation gypsum (FGDG) and phosphogypsum (PG) into cemented paste backfill (CPB). The mechanical strength of CPB and the binder paste properties (i.e., hydration heat, hydration evolution, acid erosion resistance, and leachability) were investigated experimentally. The results revealed that the addition of FGDG and PG significantly improved

This study attempts to explore the feasibility of using calcium carbide residue (CCR) as a solid alkaline activator to prepare geopolymer binders. A mixture of fly ash and ground granulated blast furnace slag was activated with CCR to prepare one-part geopolymer. A conventional two-part geopolymer activated with sodium hydroxide (NaOH) solution was also made for comparison. The CCR-activated geopolymer

This study evaluated the performance characteristics of binders and Stone Matrix Asphalt (SMA) Mixtures modified by Poly Phosphoric Acid (PPA), Carbon Nano Tube (CNT), and Styrene Butadiene Rubber (SBR). In order to investigate the rheological behavior of bitumens, linear Amplitude Sweep (LAS), rotational viscosity, Dynamic Shear Rheometer, Bending Beam Rheometer, Multiple Stress Creep Recovery (MSCR)

Particle reinforced (PR) polymer foams are promising materials for lightweight structures. In this research, compression tests were conducted on glass beads (GBs) reinforced linear low-density polyethylene (LLDPE) foams. The experimental results indicated that embedding GBs could increase the yield strength, elastic modulus and energy absorption capacity of bulk material. Analytical predictions of

For modern concrete materials and structures, how to realize the multifunctional application is still a challenge. The introduction of functional components into concrete materials is the most effective method. The present study successfully develops a new avenue to prepare rGO suspension with excellent dispersibility and stability through the combination of dispersant and ultrasonic pre-dispersion

Fiber-reinforced polymer (FRP) wrapped concrete columns are vulnerable to accidental damage or vandalism, which may cause physical cuts or tearing of the jacket, thereby compromising the confined strength and ductility of the column. This paper aims at providing a simple tool to reassess the strength under a given level of damage. Finite element (FE) models were developed to examine a variety of cuts

The following paper presents the results of research on cement composites with expanded graphite/paraffin in terms of their application in accumulative heating systems. A novel approach, using expanded graphite simultaneously as an electric conductive and as a phase-change additive, is presented. A complex additive was prepared by means of the impregnation of expanded graphite (EG) with paraffin through

The purpose of this study was to verify the time-dependent changes in the nonslip effects of a fluorine-based liquid antislip agent applied to inorganic flooring materials. Based on the coefficient of slip resistance for shoes (CSR), the nonslip effects continued until 10,000–18,000 steps after applying the antislip agent in the Wet-1 condition. The nonslip effects were insignificant in the Wet-2 condition

Photocatalyst titanium dioxide (TiO2) has been widely applied on asphalt and concrete pavements to mitigate the air pollution caused by traffic exhaust. In general, most of the TiO2 used in previous studies was pure anatase, which only exhibited excellent photocatalytic activity under ultraviolet (UV) light. Thus, N-doping method was selected to improve the photocatalytic activity, especially under

Shear is the dominant mode of masonry structural failure. A shear test of brick masonry specimen based on acoustic emission (AE) monitoring was performed in this study to assess the damage state of masonry structure reliably. AE parameters and rate-process analysis were used to analyze the damage evolution of brick masonry in shear failure from qualitative and quantitative perspectives. Results showed

Recycled aggregate concrete (RAC) specimens with different water–cement ratios and replacement levels of recycled coarse aggregate (RCA) were prepared. The effects of these two factors on the slump and compressive strength of the RAC were analyzed. The Abrams formula was used to predict the compressive strength of the RAC. The relationships between the regression coefficients and physical properties

The toughening effect of a hybrid combination of steel and polypropylene fibers on high-strength concrete (HSC) is investigated using bending, quasi-static, and dynamic splitting tensile tests. The bending strength and quasi-static splitting tensile strength of polypropylene-fiber-reinforced HSC improves only when the volume fraction of polypropylene fiber reaches 0.22%. The bending strength of st

The water inflow into a karst pipeline is characterized by great flow rate and fast flow speed, which makes it difficult to block. Phosphate cement has the characteristics of rapid setting, fast hardening, and good interface bonding, which have inherent advantages for plugging pipelines. However, under the condition of high water ratio, whether the performance of phosphate cement can still maintain

The research deals with the microstructural examination of the hardening process of dolomitic binder synthesized from dolomite flour and clay. Such binder based on its suitable properties can be considered as a perspective alternative for restoration purposes of dolomitic Roman cement – a widely used construction binder in Riga during the late 19th and early 20th century. The structures formed during

The aim of this study is to assess the effect of the strand orientation on the physical and mechanical properties of strand cement boards. To evaluate the orientation effect, non-oriented strand cement boards (i) and oriented strand cement boards (ii) were produced and assessed using two different wood species, with three-strand contents. The boards physical and mechanical properties were evaluated

More than 60% of oyster shells (OS) are discarded on the beach, which pollute the soil. At 800 °C, OS completely cracks into calcium oxide (CaO), which has the physical adsorption characteristic of a mesoporous structure. The permeable oyster shell bricks (POSB) used for purifying water were made by improving the process with OS as an aggregate. The adsorption effect on heavy metal ions in landscape