Applied Mechanics and Materials Vols. 405-408

Abstract: Engineered Cementitious Composite (ECC) is a fiber reinforced cement based composite material, which systematically designed on the basis of micromechanics and engineered to achieve high ductility under tensile and shear load. The article introduced the development of ECC as advanced construction material, shown different mechanical properties of ECC, tensile strength, compressive strength, bending strength, shear strength. And in light of recent and future full-scale field applications of ECC were also summarized.

Abstract: This paper presents the results of an inquiry into the comparative thermal performance and economic viability of interlocking block and clay brick. To this end, two test rooms of 2.4 m width, 2.4 m length and 2 m height were built. The first room was constructed using interlocking block wall whereas the second room used commercial clay brick wall. Data recorded included room temperature, inside and outside surfaces temperatures of all walls, and solar intensity. The experimental results showed that heat conducted better through the interlocking block than through the clay brick. This was not surprising because the thermal conductivity of the interlocking block is 234% higher than the clay brick. However, the cost of interlocking block wall was lower than the clay brick wall by 34.5%. An economic analysis indicates that the payback period of the clay brick in tandem with a 1 ton, split-type air-conditioner depends on the indoor set-point temperature. The payback period extends over a considerable time, and as such, the interlocking block represents the most cost effective alternative for wall construction.

Abstract: With the rapid development of construction, the amount of sand used in construction is increasing, and the river sand resources is difficult to meet the growing demand for river sand. With the awareness of ecological protection in recent years, the country have gradually taken measures to limit the over-exploitation of the river sand. Using sea sand to produce building materials is a general trend, such as sea sand concrete. In this paper, using sea sand and river sand to make concrete, and comparing the performance of them. Studies have shown that, compared with the ordinary concrete, the strength of the sea sand concrete modified by colloidal crystal has improved significantly.

Abstract: Study on the geopolymers has been a history of nearly 40 years, because of its huge comparative advantage and attractive prospect, has become a hot research field of international materials.In this paper, based on the history and the present status of geopolymers cementitious materials development, summarized geopolymer cementitious material in the selection of raw materials, the activation agent development,preparation process research, cementitious material properties, mechanical properties, durability and engineering applications. progress made and trends.On this basis, expounded the problem of large-scale widely used the geopolymers need to continue to address, and pointed out the direction for its further research and application.

Abstract: In order to solve the problem of high dependence on manufacturers or high blindness when warm mix agents are chosen in project. On the basis of the action mechanism that the agents can reduce viscosity of asphalt so that the asphalt mixture can be mixed at low temperature, an investigation on the extent of reducing viscosity on construction temperature of these agents are presented when temperature and the mixing amount of warm mix agents are different. The optional mixing amount of different warm mix agents are recommended, providing a theoretical basis for the selection and application of warm mix agent in our country.

Abstract: In this paper, the influence of fly ash concretes sustained hydration heat release effect on strength size effect was studied, by using different curing temperature indoor and outdoor in winter. The results showed that the reduce of hydration heat for fly ash concrete is not conducive to ensure the strength of concrete cured outdoor or indoor in winter. However, the growth of volume is beneficial to ensure the necessary hydration heat in concrete curing, so that the size effect of concrete strength appears that the strength increases with size increasing.

Abstract: The free deformation of cellular ceramisite concrete at early-age was measured with untouched micro-displacement sensor. The results showed foam lacking stability led to shrinkage immediately after casting. Then the concrete presented expansion. After that it would shrink except thermal expansion. The change of ambient temperature led to the deformation of concrete, and a small quantity of sand had negligible effect on this type of deformation. The rate of thermal expansion was faster than that of thermal contraction.

Abstract: This paper presents some experimental results on the physical and mechanical properties of reactive powder concrete (RPC) using two different characteristics of densified silica fume (f1 and f2). The silica fume/cement ratio (f/c) varied from 15% to 35% by weight. The flow, the micromorphology by scanning electron microscopy (SEM) and the compressive strength at the ages of 3, 7 and 28 days were studied. The effects of the silica fume agglomerations on the properties of the RPC were considered and discussed. The test results indicated that the properties of RPC depended on the type of silica fume, amount of silica fume and amount of superplasticizer used.

Abstract: A series of experiments have been undertaken to investigate the effects, on compressive strength, of variable sand/cement ratios and cement grade. Ten mixtures of different s/c ratios used two kinds of cement were cast and the compressive strength at different curing ages was tested. The results indicate that the compressive strength gets lower as the s/c ratio increases for both 42.5R and 32.5R cement. For the mixtures used 32.5R cement, the 28-day compressive strength is pretty low for the s/c ratios of 1.5 and 2. The specimens used 42.5R cement have higher compressive strength than those with 32.5R cement. The compressive strength decreases from 42.5R to 32.5R cement are significantly smaller for the s/c ratios of 0.5 and 1 than the other three s/c ratios.

Abstract: This paper predicts the shear strength of high-strength steel fiber reinforced concrete (SFRC) beams without stirrups based on existing experimental test results from 5 previous studies. A suitable model was developed by performing linear regression analysis on the database. The adequacy of the model was examined from statistical point of view.