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This study aims to systematically analyze the effects of different curing temperatures, unit binder content, and the mixture ratios of ground granulated blast-furnace slag and fly ash based on ordinary Portland cement in binders on the development of concrete compressive strength. Particularly, the study evaluates strength characteristics by calculating the maturity equivalent to 28 days of curing at 20 °C. A model based on the relationship between maturity and strength was applied to predict the compressive strength, and the experimental data were analyzed to derive strength coefficients for each variable. The results showed that at a low temperature of 5 °C, the actual strength was lower than the predicted strength, leading to higher error rates. In contrast, at temperatures of 20 °C and 40 °C, the coefficient of determination (R2 > 0.90) for the predictive equation was high, and the error rates were reduced to within 10%. The study demonstrates that by combining the maturity method with the strength–maturity relationship, the concrete compressive strength can be effectively predicted under specific curing and binder design conditions. [ABSTRACT FROM AUTHOR]

WC-Ti(C,N)-Cr3C2-Co ultrafine-grained cemented carbides with different contents of C, N and Co binder phases were fabricated. Their microstructures and mechanical properties were examined, and the relationship between the existing form of Ti(C,N) and various conditions was mainly discussed. The hardness of the samples increased and their fracture toughness decreased with decreasing C content. The average T.R.S. peaked at 4.8 GPa on the low-C side. Their microstructures significantly changed when the N2 partial pressure changed. At a N2 partial pressure of 2.6 kPa, the microstructure became finer and the average T.R.S. was the highest. Meanwhile, at N2 partial pressures of 0 and 11.7 kPa, the microstructure became coarser and the average T.R.S. decreased. As the content of Co binder phase decreased, the number of WC/WC interfaces increased. The average T.R.S. was maximum at 16.4 vol% Co, and decreases with the Co content, but was higher than those of conventional cemented carbides. The existing form of Ti(C,N) changed depending on the N content. Herein, a N2 partial pressure of 2.6 kPa and low C contents were deemed optimal. [ABSTRACT FROM AUTHOR]

The cook-off tests and numerical simulations were carried out on the HMX-based PBX to study the influence of binder content on the cook-off response characteristics of PBX. The temperature change history of the powder column was obtained, and the change in temperature due to crystal transformation was observed. The response temperature of the column was obtained. In addition, the results showed that the response temperature of the PBX decreased with the increase of the binder content. Under the same binder content, the damage to a slow cook-off bomb was higher than that of a fast cook-off bomb. In the fast cook-off test, the cook-off response temperature of the HMX-based PBX was 310.3 ℃~322.5 ℃ The critical Estane content when the response grade was combustion was 5%. Under the slow cook-off conditions, the response temperature was 260.8 ℃ ~278.6 ℃. The critical Estane content when the response grade was combustion was 7%. Numerical simulation results proved that adding binder would cause a temperature drop due to the crystal transformation. The higher the binder content, the more noticeable this phenomenon was. The maximum error between the numerical simulation and the test results did not exceed 6.5%.   [ABSTRACT FROM AUTHOR]

The air voids in the bituminous mix are filled with a cementitious grout to create cement grouted bituminous (CGB) mix, which is a semi-flexible material. The material has a high resistance to permanent deformation at high temperatures and under heavy loads because of the cementitious grout used in the mixture. Despite their increased brittleness, CGB layers are more prone to cracking when used as thin (40–60 mm) surface or base layers. Increase in binder content in mix decreases air void content and grout content, which leads to reduction in rutting resistance and expected to improve the fatigue cracking resistance. The results of an investigation into the impact of aggregate gradation and binder content on the fatigue performance of CGB mixes are presented in this paper. In a four-point bending test mode at 25 °C, beam specimens of CGB Mixes made with four different aggregate gradations and four different binder contents were tested at four strain levels. The fatigue life measured at higher strain levels of 225 and 250 µε and various mechanical properties like indirect tensile strength and modulus of rupture showed good correlation. By analysing pavements with CGB layers used as the base or surface layer, the fatigue cracking susceptibility of the CGB layer in a typical highway pavement has been determined. It has been found that using the CGB mix as the surface layer is a good choice because the mix also provides a very strong rut as well as an oil and chemical-resistant layer. [ABSTRACT FROM AUTHOR]

This paper proposes empirical models to straightforwardly assess the CO2 emissions of artificial lightweight aggregate concrete (ALWC) and bottom ash aggregate concrete (BAAC). The system boundary identified for the assessment was from the cradle to pre-construction, considering component materials, production, and transport of concrete. The CO2 emission was empirically formulated as a function of the unit binder content of concrete based on the analysis of a database, which includes 413 and 90 datasets for ALWC and BAAC, respectively. In addition, after applying ALWC and BAAC to concrete structures, their CO2 emissions are compared with those of normal-weight concrete (NWC) structures considering the reduction in the cross-sectional area of members resulting from the lower self-weight of concrete. In this assessment, the concrete used for all structural members is assumed to have been produced using ordinary Portland cement (OPC), featuring a 24 MPa compressive strength. Compared with the evaluated total CO2 emissions of the NWC structures, the ALWC and BAAC structures exhibited 36% and 24% higher CO2 emissions, respectively. This is because the CO2 emission of concrete is considerably dependent on the OPC content but marginally affected by the type of aggregate used. [ABSTRACT FROM AUTHOR]

Ultra-high performance concrete (UHPC) mixtures are typically proportioned using high binder content and low water-to-binder ratio (w/b). Yet, in most cases, such recipes denote the presence of unhydrated cement and other pozzolanic materials, thus playing the role of costly fillers in the matrix. Two UHPC categories proportioned with two cement types and various binder contents ranging from 505 to 1050 kg/m3 are investigated in this study. Test results showed that the compressive and flexural strengths followed an increasing trend with binder additions, but then tended to stabilize or decrease at higher binder concentration. The highest strengths were achieved at binder contents hovering about 575 or 690 kg/m3 for 0.26 w/b mixtures prepared with river or quartz sands, respectively. The thermogravimetric analysis showed that UHPC made with higher binder contents exhibited increased mass loss at 500 °C, which corroborates the presence of increased amounts of unreacted cement compounds (i.e., CH) in matrices containing high binder content. The effect of reducing w/b and/or incorporating silica fume or metakaolin helped improving the strength of UHPC prepared with given binder content. The use of CEM I (52.5 MPa strength cement class) yielded consistently superior mechanical properties than equivalent mixtures containing CEM II (42.5 MPa strength class). The resistance against water permeability improved for UHPC containing higher binder content, suggesting that the increased cementitious phase plays a beneficial role to block the capillary pores and refine the matrix porosity. [ABSTRACT FROM AUTHOR]

• Image-based reconstruction and characterization of GDL are conducted considering different fractions of binder, PTFE, and carbon fiber. • Gas-water displacement phase diagram and its correlation with the pore structures are predicted by pore network modeling. • The phase diagram shows a tendency to transit from the viscous to capillary fingering (unfavorable), and capillary fingering to stable displacement (favorable) with an increase in binder content. • Increasing binder content will promote effective water permeability under real operating conditions. Understanding the gas-water flow dynamics in the gas diffusion layer (GDL) is one of the keys to improving the proton exchange membrane fuel cell's (PEMFC) overall performance and avoiding water flooding. Yet, the relationship between the two-phase flow and micro-scale GDL structures (including binder, PTFE, and fiber skeleton) is not well understood. In this study, three-dimensional GDL structures with different fractions of binder contents (φ b = 0 % ∼ 50 %) and a fixed porosity of 75.6 % are confidently reconstructed based on high-resolution images from the confocal microscope, implying that the addition of binder will increase the number of large pores and cause a bimodal throat size distribution through morphology analysis. Thereafter, drainage simulations are performed under a wide range of capillary number (−9 < log Ca <0) and viscosity ratio (−3 < log M < 2) by the pore network model (PNM), which robustly predicts the displacement phase diagram of viscous fingering, capillary fingering, stable displacement, and transitional regime. In the viscous fingering and stable displacement regime, the nonwetting phase saturation (S n w) is nearly the same for different φ b , implying the fluid invading pathway does not change much with the addition of binder. However, in the capillary fingering regime (refer to the actual operating conditions), S n w increases rapidly with φ b at the breakthrough time and its transient value continues to increase until the steady state, which may be attributed to the increased fractions of pores above the capillary threshold attributed by the bimodal throat size distribution. In addition, the effective water permeability increases sharply with φ b , whereas the gas permeability remains almost constant, which means such pore structure alteration by adding the binder is beneficial to water disposal in PEMFC. This research provides insights into delineating the effect of pore and throat size distribution alteration by adding binder on two-phase dynamics in GDL. [ABSTRACT FROM AUTHOR]

Highway engineers agree that if good performance is to be achieved for a flexible pavement the wearing course of flexible pavement should be improved. Water enters the dense-graded bases through cracks, gets trapped and adversely affects the pavement structure and performance under loads. The modification of bitumen by the process of adding polymers mitigates these problems. This research-based study has been carried out by the laboratory analysis firstly the optimum binder content is determined by the Marshall Mix design criterion by using the different percentages of binder content (3%, 3.5%, 4%, 4.5%), then the optimum binder content can be obtained by the graphical values, the optimum polymer content (OPC) values are obtained against (OBC). To modify hot mix asphalt (HMA) the Marshall Mix behavior has been studied thoroughly in this research. For better performance, high-density polyethylene (HDPE), low-density polyethylene (LDPE) and crumb rubber (CR) are specified for the researched-based study. By the addition of 3% LDPE in bitumen content, improvement of 44% is shown, while the addition of 3.5% HDPE in bitumen content improvement of 40% and usage of 3 % CR in bitumen content improvement of 44% is shown. The addition of 3.5% HDPE is recommended to be the best modifier and has shown better results in all aspects.

In the current study, we produce low-binder-content geopolymer parts through impact self-assembly. After sand (the filler) and a small amount of fly ash-alkaline activator mixture (the binder) are premixed, they are impacted by a hammer in a drop tower. The hammer mass is around 2∼5 kg and the drop distance is 0.2∼0.8 m. The flexural strength of the cured material is ∼5 MPa, comparable to typical portland cement. The key processing parameter is the impact momentum of the hammer. Repeated impact improves the microstructural uniformity. The low binder content helps minimize the materials cost, reduce the carbon emission, and lower the demand of class F fly ash.

Reclaimed asphalt pavement (RAP) has been widely implemented in asphalt pavement construction due to its cost benefits along with its reasonable engineering performance. With the trend of higher RAP applications, it is more critical to consider the complicated interactions between RAP and virgin binders. An unreasonable assumption of the full blending of RAP material could lead to many issues, such as insufficient virgin binder content and poor pavement durability. This paper focuses on the determination of virgin binder grades and content during the design of a high RAP content mixture by considering RAP blending effectiveness. By integrating the blending ratio parameter, a modified blending chart is proposed to determine the PG grade of the virgin binder, and a partial blending method is used to estimate the optimum virgin binder content. It is found that when an 83% blending ratio is considered in the 40%-content RAP mixture design, the differences of the determined virgin binder grade from the traditional blending chart and modified one is within 6° (one PG grade). If the blending ratio is 56% or less for a 40%-content RAP mixture, the required base binder needs to drop one PG grade (6°). Moreover, the partial blending method typically demands 0.5%–1% more virgin binder than the Superpave volumetric method, which could result in significantly improved cracking performance without jeopardizing its rutting resistance. [ABSTRACT FROM AUTHOR]

This paper highlights the strength and durability characteristics of geopolymer concrete (GPC) developed with ground‐granulated blast furnace slag (GGBS) and metakaolin (MK) as binders. Sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) were used as alkaline activators of GPC. The variable parameters considered in this research work were proportions of GGBS and MK. The optimum mix was obtained by varying the proportions in the binder content of GPC. The influence of recycled coarse aggregates (RCAs) was also assessed on the arrived optimum GPC mix and compared with natural coarse aggregates. The replacement of RCA was done at 25, 50, and 100%. The durability studies were performed on the arrived optimum mix for natural and RCA concrete. The durability properties of GPC were studied by exposing the concrete specimens to HCl and H2SO4 at 5% concentration for 7, 28, and 56 days. Acid mass loss factor and acid strength loss factor were determined at all ages. From the results, it is observed that the usage of supplementary cementitious material as a partial replacement of GGBS in GPC is improving the strength as well as durability properties of blended GPC. The comparisons of these parameters were examined for the usage of RCA proportions also. The results indicated that the inclusion of RCA up to certain proportions is showing satisfactory results compared to that of GPC with natural aggregates. [ABSTRACT FROM AUTHOR]

• The proposed mix design method produced SCCs with low binder contents. • The use of ground fly ash led to good durability indicators. • The CO 2 /MPa·m3 emission is among the lowest reported in the literature for HPSCCs. • HPSCCs with the lowest reported binder content (365 kg/m3) were produced. The use of high-performance concrete (HPC) is widespread as an eco-efficient building solution because it provides greater durability and, hence, a longer lifetime than conventional concrete, reducing the need for repairs and demolitions. In addition, HPCs require lower binder contents per unit of compressive strength. However, self-compacting HPCs (HPSCCs) generally require high binder contents to ensure the fresh state stability of the concretes, which could hinder the ecological advantage. Thus, this work aimed to produce HPSCCs with low binder contents. A mix design method was proposed to optimise the material proportions. A fine fly ash was used to replace Portland cement from 0 to 30%. The rheological properties of the SCCs were evaluated by the workability tests slump flow, T500, V-funnel, L-box and VSI. Compressive strength, resistance to chloride ion penetration, volume of permeable voids and capillary water absorption were determined at 28 and 91 days. Finally, the CO 2 intensity (kg CO 2 /m3·MPa) of the mixtures produced was estimated and compared to those of HPSCCs reported in the literature. The mix design method allowed for the production of SCCs with 365 kg of binder/m3 of concrete, with slump flow of 700 ± 25 mm and stable in the fresh state (VSI of 0 or 1). The fly ash-containing concretes showed compressive strengths up to 59 MPa at 28 days (10% fly ash) and 71 MPa at 91 days (20 and 30% fly ash), with good indicators of durability: down to 403 Coulombs for RCPT and up to 41.8 kΩ·cm for surface electrical resistivity. The CO 2 intensity of the concretes produced are among the lowest reported in the literature for HPSCCs (down to 4.7), together with the lowest binder content reported for this type of concrete (365 kg/m3 of concrete). [ABSTRACT FROM AUTHOR]

Highlights • The FBGs were used to measure CTB temperature and internal strain evolution. • In the liquid stage, the binder content had no effect on settlement behavior. • CTB internal strain was influenced by combined chemical and thermal effects. • No significant change occurred in settlement and strain in the hardened stage. Abstract The philosophy of the use of backfill is to return much of tailings waste to underground voids and increase working place stability to safely extract more minerals. The key issue for the safe and efficient design of cemented tailings backfill (CTB) structure is its mechanical properties and interaction with the surrounding rock. As a cemented material, CTB's strength is a function of hydration degree. As hydration is an exothermic reaction and results in net volume reduction, thermal expansion and chemical shrinkage occur simultaneously in the mixture. Each CTB component plays a significant role during this process and the most important factor is the binder content, because it influences the amount of cement hydration products that provide binding phases between tailing particles. In this paper, a number of fiber Bragg gratings (FBGs) were directly embedded into the 7-day cured CTB specimens to measure their temperature and internal strain evolution, with settlement development measured by Linear Variable Differential Transformer (LVDT). The experimental results showed that binder content had a significant effect on CTB temperature and internal strain evolution. Furthermore, the evolution of internal strain and settlement was an indicator of the transformation in different stages (such as fluid, skeleton formation and hardening) during the hydration process. [ABSTRACT FROM AUTHOR]

This paper documents the second part of a forensic investigation performed to determine the causes of loss of skid resistance and bleeding in two pavement sections rehabilitated with an ultra-thin bonded wearing course. The first part of the study explored the influence of the aggregate fraction on the loss of skid resistance. This second part focuses on binder-related issues to understand the cause of the bleeding. A detailed investigation was performed on cores removed from both sections to quantify the binder content profile with depth. The chemical characteristics of all the recovered binders were determined using Fourier transform infrared spectroscopy and X-ray fluorescence spectroscopy. The results suggested that bleeding due to excess binder in the tack coat contributed to this deleterious performance. Chemical analysis identified an upward migration of a part of the binder from the interface and confirmed this hypothesis. [ABSTRACT FROM AUTHOR]

Pelletizing is a common optimization process of the mechanical properties of various powder materials. The improvement of flow behaviour, dosage and the increase of bulk density are only a few the goals that this size enlargement concedes. Anyway, the properties of the produced pellets depend on many factors, whose influence is not completely studied. In order to investigate the effect of process parameters on the mechanical strength of final products, industrially produced alumina oxide (γ -Al2O3) granules as primary model particles were pelletized in a laboratory rotating pan-pelletizer (spheronizer). The processing time for all pelletizing batches was 20min. Solution of viscoelastic polymer-hydroxypropyl methylcellulose was used as binder. Its concentration was increased until finding of the most suitable binder content for the model pellets. The rotational velocity of the pan-pelletizer was varied in order to find the optimal speed, which provides pellets with improved properties. The influence of the process parameters on the received pellet product properties like density and porosity, size distribution, breakage behaviour and breakage probability was also analysed. The solid bonds between the single primary particles were investigated using light and scanning electron microscope. The conclusions from the experimental work help us to understand the basics of pelletizing processes and tend to develop and facilitate the operating principle with particle populations in science and industry. The result should provide base for carrying out of Discrete Element Method simulations, which should enlighten the process of irregular pellet breakage. [ABSTRACT FROM AUTHOR]

Herein, we investigate the effects of catholyte feed method and anode binder content on the characteristics of anion exchange membrane water electrolysis (AEMWE) to construct a high-performance electrolyzer, revealing that the initial AEMWE performance is significantly improved by pre-feeding 0.5 M aqueous KOH to the cathode. The highest long-term activity during repeated voltage cycling is observed for AEMWE operation in the dry cathode mode, for which the best long-term performance among membrane electrode assemblies (MEAs) featuring polytetrafluoroethylene (PTFE) binder–impregnated (5–20 wt%) anodes is detected for a PTFE content of 20 wt%. MEAs with low PTFE content (5 and 9 wt%) demonstrate high initial performance, rapid performance decay, and significant catalyst loss from the electrode during long-term operation, whereas the MEA with 20 wt% PTFE allows stable water electrolysis for over 1600 voltage cycles. Optimization of cell operating conditions (i.e., operation in dry cathode mode at an optimum anode binder content following an initial solution feed) achieves an enhanced water splitting current density (1.07 A cm −2 at 1.8 V) and stable long-term AEMWE performance (0.01% current density reduction per voltage cycle). [ABSTRACT FROM AUTHOR]

We report results from an experiment on high-pressure compaction of lunar soil simulant (LSS) mixed with 2–5 wt% polymer binder. The LSS grains can be strongly held together, forming an inorganic-organic monolith (IOM) with the flexural strength around 30–40 MPa. The compaction pressure, the number of loadings, the binder content, and the compaction duration are important factors. The LSS-based IOM remains strong from −200 °C to 130 °C, and is quite gas permeable. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of cement replacement by high contents (30%vol and 60%vol) of limestone fines on rheological behaviour and mechanical properties of mortars as well as on the bond strength of mortar-ceramic interface. Mortars with 75%vol of sand and 25%vol of fines were produced using cement and two limestones having different particle size distributions and surface areas. A similar set of mortar compositions was also prepared using a polycarboxylate-based dispersing admixture. Rheological behaviour of the mortars varied depending on type and content of limestone fines, and whether the admixture was added. Elastic modulus and tensile strength of the mortars decreased with the increase of limestone content. However, for replacement rates of 30%vol, the tensile bond strength between mortar and ceramic block increased, likely because of ITZ densification. The dispersing admixture improved the tensile bond strength of all compositions without necessarily increasing their mechanical properties. The obtained results were compared to others available in the literature. [ABSTRACT FROM AUTHOR]

Tungsten carbide has both industrial and military applications, from high strength end mill dies and geological drilling, to kinetic energy penetrators. In these extreme environments, an understanding of the dynamic fracture properties and the potential influence of grade microstructure is necessary. The present work investigates fracture behavior of cobalt and nickel cemented tungsten carbide with varying grain size and binder content. Notched hardmetal WC-Co and WC-Ni samples are impacted under mode-I (opening) fracture conditions, and the dynamic stress intensity factor is determined from digital image correlation using ultra high-speed imaging, and compared with quasi-static values. In both grain size and binder content variants examined, the dynamic fracture toughness increased from the quasi-static by a factor of 1.51-2.44. In addition, a 7% increase in cobalt binder content (while maintaining nominally identical average grain size) resulted in a 20% increase in quasi-static fracture toughness, from 8.62 to 10.38 MPa $$\sqrt{\text {m}}$$ ; while the same binder increase resulted in a 34% decrease in critical SIF from 21.07 to 15.72 MPa $$\sqrt{\text {m}}$$ . The 6% nickel binder WC was found to have a 4.5% higher quasi-static fracture toughness than the 6% cobalt binder WC of the same grain size, but a statistically insignificant difference under dynamic loading. Overall, there is a 28% increase in the quasi-static fracture toughness of tungsten carbide samples with an increase of average grain size from 1 to 3 $$\upmu $$ m, and under dynamic loading the larger grain WC shows a nominally identical increase in fracture toughness. These findings are discussed within the theory of classical dynamic fracture mechanics, the implications of the experimental configurations pursued, and the microstructural features are examined using fractography. [ABSTRACT FROM AUTHOR]

Asphalt concrete is composed primarily of aggregate and asphalt binder. By volume, a typical Hot Mix Asphalt (HMA) mixture is about 85% aggregate, 10% asphalt binder, and 5% air voids. Bitumen is very important as a binder material in asphalt concrete. However, the cost of the bitumen is relatively high. For this reason, highway professionals are looking for modifiers to decrease the bitumen content used in the asphalt pavement. In this study, waste frying oil (WFO) is used as a modifier to modify the bitumen. As a result, by adding WFO into the bitumen, optimum binder content of a mixture was decreased from 5.125% down to 4.575%. So that, roads constructed with WFO modified bitumen are sustainable because of decreasing the bitumen rate used in the mixture. In addition, softening point of the modified bitumen is decreased (up to 82%) while the penetration value is increased (up to 240%) by modifying the bitumen with WFO. The tensile strength ratios of the modified asphalt specimens are all above the minimum specification limit, 80%. Finally, required temperature for fast self-healing is decreased by modifying the bitumen with WFO. Specimens prepared with WFO modified bitumen are healed compared to the reference specimen. [ABSTRACT FROM AUTHOR]

To improve the cell performance for alkaline anion exchange membrane water electrolysis (AEMWE), the effects of the amount of polytetrafluoroethylene (PTFE) non-ionomeric binder in the anode and the hot-pressing conditions during the fabrication of the membrane electrode assemblies (MEAs) on cell performances are studied. The electrochemical impedance data indicates that hot-pressing at 50 °C for 1 min during MEA construction can reduce the polarization resistance of AEMWE by ∼12%, and increase the initial water electrolysis current density at 1.8 V (from 195 to 243 mA cm −2 ). The electrochemical polarization and impedance results also suggest that the AEMWE performance is significantly affected by the content of PTFE binder in the anode electrode, and the optimal content is found to be 9 wt% between 5 and 20 wt%. The AEMWE device fabricated with the optimized parameters exhibits good water splitting performance (299 mA cm −2 at 1.8 V) without noticeable degradation in voltage cycling operations. [ABSTRACT FROM AUTHOR]

Cement emulsified asphalt mixtures are widely used as construction and building materials in pavement engineering and high-speed railway engineering. Consequently, engineering properties of the mixtures have been paid more attention, which can be enormously affected by variations of aggregate gradations and binder (emulsified asphalt and cement) contents. Therefore, the objective of this study was to evaluate the effects of aggregate gradations and binder contents on engineering properties of the cement emulsified asphalt mixtures. Three aggregate gradations were designed to calculate fractal dimension values based on fractal geometry. Two binders (emulsified asphalt and cement) and six contents were utilized to prepare the mixture specimens. Engineering properties of the mixtures were tested in laboratory, such as high-temperature stability, cracking resistance properties, moisture susceptibility and adhesion characteristic. In addition, scanning electron microscopy ( SEM ) and optical microscope ( OP ) were adopted to conduct a microstructure analysis of cement emulsified asphalt mixtures. The results showed that a given aggregate gradation was proved to have a specific fractal dimension value. Gradation with great fractal dimension values represented high surface irregularity, but didn’t always get good mechanical properties. The reasonable aggregate fractal feature and addition of cement both improved the high temperature stability of cement emulsified asphalt mixtures. Indirect tensile strength and moisture susceptibility were mostly affected by aggregate gradations and binder dosages. The Cantabro loss index was mainly dependent on aggregate gradation other than emulsified asphalt and cement contents. Reasonable aggregate gradation fractal and suitable binder contents jointly played an importance role in improving performance of cement emulsified asphalt mixtures. [ABSTRACT FROM AUTHOR]

In this paper, a (Ti,W,Ta,Mo)(C,N) cermet material was prepared by spark plasma sintering. The formation of (Ti,W,Ta,Mo)(C,N) solid solution was characterized, and the effects of the sintering behavior and the binder content on the microstructure and mechanical properties of (Ti,W,Ta,Mo)(C,N) cermet materials were investigated. The results shown that a core-shell microstructure with cyclic gradient distribution was formed through the dissolution-reprecipitation mechanism, and the sintering behavior was improved and the relative density was increased. The optimized binder content can promote the dissolution and diffusion of Ti(C,N) particles. At the same time, the crack deflection and crack bridging caused by the core-shell microstructure improved the fracture toughness of the cermets, and the lattice distortion caused by fine grain and solid solution enhanced the flexural strength. When the binder content is 9 wt%, the mechanical properties of the cermet is better, the Vickers hardness, the flexural strength and the fracture toughness reach 18.17 ± 0.14 GPa, 1510.5 ± 47 MPa and 8.16 ± 0.40 MPa·m1/2, respectively. • In this paper, (Ti,W,Ta,Mo)(C,N) cermets with core-shell microstructure were sintered by spark plasma sintering. • The better densification degree was found when binder content was 9 wt%. • When the binder content is 9 wt%, the grain refinement and mechanical properties of the cermet is better. • The core-shell microstructure increased the crack deflection and improved toughness of cermet material. [ABSTRACT FROM AUTHOR]

The effect of compaction degree and binder content on performance properties of asphalt mixtures of an asphalt concrete type for wearing and binder courses are described in the paper. Measurements of stiffness modulus by two-point bending test on trapezoidal shaped specimens, fatigue characteristics, and resistance against frost cracking by thermal stress restrained specimen test have been performed on selected asphalt mixtures. The main aim of the experimental part was to determine to what extent the performance properties of the individual mixtures will be affected when decreasing the compaction degree by 3% in comparison to the optimal design, i.e. from 100% to 97% degree of compaction. This decrease simulates incomplete degree of compaction of courses during pavement construction, which is common and accepted during acceptance tests and it is in accordance with the Czech regulations. Then, the decreased dosage of binder content by 0.5% is simulated, which is the boundary parameter for lowering the binder content within the acceptance test. The results of performance testing have been affected by lower compaction degree and lower binder content have been used as course parameters and integrated into a mathematical model of a commonly used pavement construction, which is presented by a multi-layered linear elastic model based on the use of Burmister‘s equations. The outcome of the paper is a description of the effect of lower degree of compaction and lower binder dosage on the lifetime of a pavement construction.