Applied Mechanics and Materials Vols. 423-426

Abstract: Based on the special performance of the tunnel, a low temperature, flame-retardant and safety environmental noise reduction asphalt mixtures was developed. The result of paving the experimental road section showed that environmental protection and safety bituminous mixture compared with ordinary hot mix asphalt mixture has low temperature, fire-retardant, noise reduction characteristics. Keywords: road tunnel; viscous and environment asphalt; Mixture design; Pavement performance;test road

Abstract: This study aimed to investigate the effect of temperature on stiffness modulus of asphaltic concrete. The asphaltic concrete mixture were prepared based on Marshall Mix Design method using two different types of bitumen, the 80/100 penetration grade bitumen (80/100 PGB) and Styrene-Butadiene-Styrene (SBS), both with five percent bitumen content. Indirect Tensile Stiffness Modulus (ITSM) test of 1000 N loading was then performed at three different temperatures (25 °C, 30 °C and 40 °C). The results showed that stiffness modulus decreases with increases in temperature for both 80/100 PGB and SBS, which shows the important role of temperature to stiffness modulus of asphaltic concrete. Also, the results showed a higher stiffness modulus for SBS mixtures compare to that of 80/100 PGB mixtures.

Abstract: With soil-rock mixture (SRM) as the object of study and compaction test as the means, the paper studies the compactability of the SRM and analyzes the compactability influencing factors and engineering properties after compaction. Studies show that the soil engineering properties of compacted SRM are greatly improved, so it is a building material with broad application prospects.

Abstract: In view of the importance of recycled aggregates concrete with primary aim to minimise environmental impacts from construction waste, this study was conducted in order to investigate the effects of recycled aggregates on concrete elastic modulus. The outcomes indicate that type of recycled aggregates influences the development of concrete elastic modulus. In general, the use of recycled aggregates posts significant reductions in concrete elastic modulus.

Abstract: Recycled aggregate differs from primary aggregate in that it constitutes of two types of materials: the primary aggregate and the attaching cement mortar. This study was conducted in order to investigate the effects on water-cement ratio for concrete cast with recycled aggregates derived from different origins (hollow blocks & structural concrete elements) and different mixed proportions of recycled aggregate contents. The outcomes of test indicate that higher water cement ratios are required for concrete cast with recycled aggregates as compare to those cast with primary aggregates. Also there appear no obvious relationships or consistencies that can be drawn among types of recycled aggregate.

Abstract: In this paper, red mud of aluminum industrial residue has been studied to make the glass-ceramic, quartz sand, magnesite, fluorite and red mud was mixed to melt, molten glass was poured into the model in shape, then annealing, glass-ceramic was make, the color of glass-ceramic is brown or black, the crystals in glass-ceramic body is iron oxide by XRD, Strength, the expansion coefficient and morphology of the sample were measured. Glass surface color depends on the melting temperature.

Abstract: Compressive strength and AC impedance of mortar made with water-glass-activated slag were investigated as a dependence of modulus (0.5-2.0) and dosage (2-6%) of the water-glass. Results shown that when the dosage of water glass is 2- 4 %, the modulus of the water glass has a little effect on the compressive strength. In the case of the dosage of water glass is beyond 4 %, when modulus of the water glass change from 0.5-1.0, the compressive strength obviously increases with increase of modulus of water glass and when modulus of the water glass change from 1.0-2.0, the modulus of the water glass has a little effect on the compressive strength. The strength increases with increase of the dosage from 2 to 6%. In the case same dosage and modulus, there is a rather good power correlation between the bulk resistance and the activated age. With increase of the dosage, the bulk resistance significantly decreases when the dosage is below 4%. The decreasing degree is small when the dosage is beyond 4%. The decreasing degree derived from the dosage increases with the activated age. The effect of the modulus on the bulk resistance depends on range of the dosage. However, it can be regarded that when the dosage is 4% and 6%, the modulus has small effect on the bulk resistance in the case of all the dosages.

Abstract: The influences of fly ash and phosphoric acid on water-resistant property and the microstructure of magnesium oxychloride cement (MOC) were investigated in this paper. It is found that the improvement of the water-resistance of the MOC incorporated with phosphoric acid can be attributed to the dramatic decrease in the quantity of crystallization points. In addition, the new Mg₂PO₄(OH) phase can also prevent the dissolution of 5-phase. And the mechanism of the water-resistance of the MOC mixed with fly ash is due to the Ca₂MgSi₂O₇ phase and the glass phase which are filled into microscopic cracks and skeleton empty.

Abstract: Peridotite containing high crystal water is used as concrete aggregates in this research. The mineral composition and thermal stability of peridotite are experimentally analyzed, and the concrete mix proportion design is optimized. The neutron shielding performance of peridotite concrete specimens are tested using ²⁴¹Am-Be neutron source. The transmission data of different thickness and different energy neutron are calculated. It concludes that peridotite concrete has a good performance in neutron shielding and peridotite is an excellent neutron shielding material.

Abstract: To study the impact of mineral admixtures and water-binder ratio on carbonization resistance of high performance manufactured sand concrete, high performance concrete of single mixed flyash, admixing silica fume and no admixture were compounded, carbonation depth of 3d, 7d, 14d and 28d was recorded by the way of indoor test. The test results show that with the decrease of water-binder ratio, carbonation resistance of high performance manufactured sand concrete increase, and when the concrete compressive strength is over 55Mpa, carbonation resistance is good, and when water-binder ratio is lower than 0.38, the impact of mineral admixtures on the carbonation resistance can be neglected.