Applied Mechanics and Materials Vols. 357-360

Abstract: The Modification mechanism of the Polymer Modified Cement Concrete was studied by the DTA,SEM and MIP with the confirmation of lab test results. The research indicated: the more dosage of the polymer, the less content of the Ca(OH)2 in the Cement hydrated product. The pore structure was improved evidently simultaneously. The polymer film tend to more complete and interweaved with Hydration products. Therefore the netted structure was formed and the flexiblity of concrete was increase greatly. Lab test results also proved it：when continued adding the polymer, the performance of concrete improved remarkably.

Abstract: It is of great significance for concrete to be cured using controlled permeability formwork of nonwoven fabrics especially in dry area. CPF can improve durability of concrete through decreasing the ratio of water and cement in concrete surface. CPF could also retain the water within it. The role of concrete curing using CPF or not is test by MOIST200B type microwave moisture meter. In addition, the permeability of concrete surface between the concrete which use CPF or not is analyzed through the air permeability test, the initial surface absorption of concrete test (ISAT). The testing results indicate that there is little effect on curing of concrete using controlled permeability formwork liner.

Abstract: In this paper, the usage of high strength concrete are analyzed, based on this analysis, high strength concrete’s engineering problems existing in Chinese practical application are discussed. Reasonable structural design theory according to high strength concrete are put forward , this method is more suitable, especially, for statically indeterminate structural systems. In the end,our suggestions are given in an effort to improve the application of high strength/performance concrete in the construction of China.

Abstract: Article discusses the use of fly ash in concrete production. It is focused on the chemical and physical properties of fly ash and in particular the mechanical properties of mortar, where ash was added in amounts of 10% to 70% by weight of cement. Furthermore, the mechanical properties of the samples compared to the same dose of mixing water and samples that have the same consistency of fresh mortar, different batch mixing water.

Abstract: In this paper, microstructure of brucite fiber was introduced briefly and its physical and chemical properties were given. Disperse method of fiber applied in concrete has been introduced. The effect of compressive strength, flexural strength of concrete and cement mortar by the addition of brucite fiber have also been discussed. The mechanism that fiber can reinforce concrete has been discussed. The results showed that the diameter of brucite fiber changes from micrometer scales to nanometer dimension with the dispersing action of water reducers. Brucite fiber can exert its high tensile strength on concrete and improve the mechanical property of cement motar and concrete. Life of bructie fiber reinforced composite material can be prolonged by the addition of brucite fiber.

Abstract: With the powerful regression and fitting of support vector machines in uncertainty and the non-linear,based on the determination of the content of the coarse aggregate and characteristic parameters, this paper established a predictive model of self-compacting concrete elastic modulus based on support vector machine.Through analysis and comparison with experimental results, it proves the accuracy and effectiveness of the model.

Abstract: This study is intended to propose the performance standards and performance test standards of artificial rocks through investigation of standards, guidelines and other literature home and abroad, testing, and site-survey. As a result, the selected performance requirements include a total of 15 items: structural safety (flexural, compressive, impact strength), durability (crack, corrosion resistance, fire resistance), landscape (texture, discoloration, color), environmental load reduction (CO₂ reduction rate, materials recycling rate, water quality and soil), and ecological performance (biodiversity, ecological similarity, ecosystem function damage reduction).

Abstract: Foam concrete is used in building energy saving and heat preservation project, and its refractory performance is very important to improve the fire resistance ability of the building. In this paper, fireproof property of the foamed concrete were studied.In the simulation fire conditions, compressive strength value of foamed concrete in different density, different calcination time, and different water content cases were determined first, then influence of these conditions on the foamed concrete refractory performance were researched. The results showed that foamed concrete compressive strength loss rate increase with density decreases in fire cases; Density of 300kg/m³ and 800kg/m³ foam concrete block, calcinated under 800°C fire in 20 min, its compressive strength loss rate were 66.3% and 25.5% respectively; The same density of foamed concrete compressive strength gradually reduce with the increase of calcining time; Moisture content on the different density of foam concrete affect differently on the fire safety. Foamed concrete is incombustible, but its compressive strength reduced due to fire inflammable material of high temperature calcined.

Abstract: Due to the excellent physical and chemical properties of low melting point, high stability, low vapor pressure, and adjustable solubility, the ionic liquid is widely used in the dissolution of cellulose, regeneration and applied research. This thesis selects the ionic liquid to dissolve the wooden ponder in the processed wood residues and observes its dissolution behavior including the dissolution process of the cellulose in the ionic liquid and the cellulose dissolution as well as its regeneration mechanism. It turns out that the chemical structure of successfully prepared gel-type wood composite material does not changes and its microstructure retains a complete timber microscopic structure. For the fiber bundle formed after the celluloses dissolution, one part functions as the support skeleton, another forms a closed three-dimensional crosslinked network, which possesses stable chemical and physical properties. The gel-type wood composites owns suitable visual characteristics, which can render the "natural", "comfortable", "simple and elegant", and "crisp" visual psychological impression.

Abstract: This paper studied the mechanical performance of bamboo fiber reinforced concrete through a series of compression, splitting and flexural tests. The comparative variables are the length and volume ratio of the bamboo fiber. The test results show that concretes splitting tensile property has obvious improvement when bamboo fibers are added, but the enhancement to the compression property and flexural property is not obvious.