To reduce the structural deterioration of mass concrete structures from temperature cracks, and lower energy consumption caused by traditional hydration heat cooling process, this paper reports preparation temperature-controlled phase change aggregate (PCA) a vacuum compaction method using light high-strength black ceramite No. 58 fully refined paraffin wax as material (PCM), encapsulation tech...

In this study, first by surveythe parameters affecting the compressive strength, such as water to cement ratio, cementgrade, silica fume to cement percentage, and the various ratios oflight weight aggregate LECA, to total aggregate, Taguchi method is used, to test 9 mix designsobtained the mix design optimization. Since lightweight concrete is brittle like normal concrete, to resolve this probl...

Concrete is the safest and sustainable construction material which is most widely used in the world as it provides superior fire resistance, gains strength over time and gives an extremely long service life. Its annual consumption is estimated between 21 and 31 billion tones. Designing a concrete mix involves the process of selecting suitable ingredients of concrete and determining their relati...

Introduction: Various surface treatments have been used to improve the adhesion of resin cement to zirconia restorations. The present study aimed to investigate the effects of different surface treatments on the bond strength of resin cement to zirconia (Y-TZP) in clinical practice. Methods: thirty square Y-TZP samples were classified into three groups of 10, including group SB (50 µm sandblast...

introduction: the aim of this study was to determine the effect of different luting agents on fracture resistance of endodontically treated teeth restored with casting post. materials and methods: in this experimental study, forty extracted human maxillary central incisors teeth with the mean length of 23mm were randomly assigned in to four groups. all the studied teeth were caries free without...

objective: a clinical challenge of using zirconia frameworks is to achieve adequate bond with different substrates. this study aimed to evaluate the effect of bioglass and silica coating of zirconia substrates on microshear bond strength of resin cement to tetragonal zirconia. methods: this laboratory experimental study was conducted on zirconia discs. a total of 120 ytzp zirconia (zirkonzahn) ...

The utilization of cemented tailings/paste backfill (CPB) by the mining industry is becoming increasingly important. However, it has been difficult to analyze the economic usage of CPB for fine unclassified tailings. Therefore, the physical and chemical properties of fine unclassified tailings, sampled from the Sijiaying Mine, were first analyzed in this study. After this, active excitation of ...

The use of additives to improve the quality of cement grouts is crucial for civil engineering, especially in foundation construction. This article presents experimental data concerning the compressive strength, elastic modulus, bleeding and injectability of microfine cement grouts modified with epoxy and acrylic resin emulsions. Strength properties were obtained at different curing ages. For fu...

the effects of adding nano-silica particles on the compressive strength and water permeability of concrete and its comparison with that of micro-silica were investigated in this work. the effect of combination of nano- silica and micro-silica were also studied in this work, which resulted in an increase in compressive strength of concrete in comparison with other concrete specimens tested in th...