The effects of using recycled concrete aggregate (RCA) as coarse on the equivalent substrate stiffness and mechanical properties sustainable alkali-activated were investigated in this paper. High-calcium fly ash (HFA) commercial silica fume (SF) used precursors for producing high-calcium (AAHFAC). Sodium hydroxide (SH) sodium silicate (SS) solutions alkaline activator with constant SS/SH ratio ...

The investment casting of reactive Ti and TiAl alloys requires the use of selected ceramics in the face-coat layer to prevent the reaction between the cast metal and ceramic shell, avoiding the formation of a hard layer at the metallic components surface. This work aims to study the influence of ceramic shells composition in some of its characteristics such as flexural strength, friability and ...

Adhesion between asphalt and aggregate plays an important role in the performance of asphalt mixtures. A low-frequency adhesion fatigue test was proposed in this paper to study the effect of environment on the asphalt-aggregate adhesion system. The stress-based fatigue model had been utilized to describe the fatigue behavior of thin-film asphalt and aggregate system. The factors influencing the...

Sodium silicate solutions are used as an eco-friendly binder in the casting process. However, strength of sand molds using sodium is reduced because their low humidity resistance. In this study, silica nanoparticles were added to a solution with constant SiO2/Na2O ratio improve resistance inorganic binder. The effects dissolution times and particle size on flexural was also investigated. physio...

An experimental investigation on the chemical, physical, mechanical, and shrinkage of seawater sea sand-based ultra-high-performance concrete (UHP-SWSSC) with supplementary cementitious materials (SCM) (i.e. slag silica fume) is reported. Several mixes were designed varying proportions SCMs (25%, 37.5%, 50%, 62.5% binder), aggregate source, water-to-binder ratio. Heat evolution, density, workab...

As part of the casting process, foundries create sand molds and cores to hold the molten metal to specific dimensional tolerances. Although most of the waste foundry sands (WFSs) from this process are land filled, there is great interest in diverting them for use in agricultural and geotechnical applications. One potential limitation to their beneficial use is concern that the WFSs will leach h...

Binder drainage test is widely used to set an upper limit to the design binder content of porous asphalt. However, the presence of high amount of fine particles in the drained binder may affect the accuracy of the test result. This paper presents a study to characterize the composition and particle size distribution of fine particles accumulated in the drained binder. Fine aggregates and filler...

Multiple studies propose the incorporation of waste glass into concrete as a sustainable solution covering many aspects, including preserving natural resources, utilizing materials and reducing cost. In present study, suitability different types flat from local industry supplementary binder or aggregate was examined. Different protocols were followed based on European American Standards. The ch...

Recent tendencies in concrete technology have been towards to high- performance concrete with a low water-cement ratio. However, high performance concretes have some problems. One of the problems is early-age cracking due to autogenous shrinkage. This study presents the results of an experimental investigation carried out to evaluate the autogenous shrinkage of high-strength concrete. Accordi...