Applied Mechanics and Materials Vols. 368-370

Abstract: The maturity method applies the fundamental concept that concrete strength develops with time as the cement hydrates and releases heat. The rate of strength development at early ages is related to the rate of hydration of cement. In this investigation, 27 Self-consolidating concrete (SCC) mixtures made with various mixture proportioning parameters, including maximum size and type of aggregate, type and content of binder, and w/cm were evaluated. Based on this investigation, SCC proportioned with 0.33 w/cm exhibited lower maturity at the same strength level compared to that with 0.38 w/cm; and for the same 0.38 w/cm, SCC made with Type MS cement had higher maturity compared to those proportioned with Type HE + 20%FA and Type HE + 30%S, at the same strength level.

Abstract: A model to calculate the average daily shading factor of flat-plate solar collector array installed on the limited horizontal roofs has been developed. The relations between the average daily shading factor and the aspect ratio of the collector array have been deeply studied. The results show that for the collector array with the floor area from 50 m² to 1000 m², the smaller the floor area, the faster the increase of the average daily shading factor with the increase of the aspect ratio. The average daily shading factors do not exceed 0.085 for the low latitude regions (lat. 30^o N), whereas the maximum average daily shading factors can reach 0.140 when the latitude is close to 40^o N.

Abstract: The nonlinear finite element analysis for the flexural behavior of the concrete beams reinforced with CFRP-PCPs Composite Rebars,which was a new structural form, has been studied in ANSYS. The effects of material nonlinearities of concrete £¬steel rebar £¬CFRP rebar were considered in the analytic model. Load-displacement curves were received through calculation in this paper. Compared the present result with the experimental results has proved that the model provided is correct and convenient for the analysis of the beams.

Abstract: Six mixtures with different ratios (0%, 50% and 100%) were designed to investigate the compressive strength, elastic modulus and Poissons ratio of geopolymeric recycled concrete (GRC). The mechanical properties and failure mechanism of recycled concrete (RAC) and GRC were tested and discussed by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX). The results show that, GRC concretes are stronger than RAC concretes due to different reaction products and better microstructure in interfacial transition zones (ITZs). The EDX results show that the higher compressive strength with higher Si/Al ratio.

Abstract: In this paper the environment protection type blowing agent replacement process had been briefly introduced. Experimental study had been conducted on the burning and thermal insulation performance of the traditional CFC-11 (Freon) and typical environment-friendly blowing agent, and the influence rules of density and gas phase thermal conductivity on the main performance were obtained

Abstract: To form a carbon footprint calculation method for cement manufacture, a detail analysis is conducted on the essential factors of the manufacturing process of the cement industry in Fujian Province. From the analysis result, the calculation model and calculation process for cement manufacture carbon footprint is formed to provide a scientific basis for the carbon footprint calculation.

Abstract: Gypsum walls are a green product that helps to save energy and protect the environment. This paper investigates the shear strength of glass fiber reinforced gypsum (GFRG) walls fully or partially filled with concrete in the hollow cores. Eight full scale GFRG walls were tested. The shear performance of the tested walls, including the shear failure mode, hysteresis responses, the ultimate shear strength were studied in the paper. A design procedure for the shear strength of the concrete filled GFRG walls is developed.

Abstract: This study visited Japanese landscape construction practices and divided paving into 4 categories: smooth paving, brick paving, permeable paving and wooden paving. We try to summarize characteristics of each type and analysis how to use them. Through Japan paving materials research attempts to find starting point of improving the quality of landscape construction, starting from the landscape materials, so as to promote the development of landscape industry.

Abstract: This paper use dust particles which is produced by crushing limestone to replace the same amount of cement in different proportions, study the performance of cement mortar, and determine the best dosage of limestone dust. Its size is less than 0.08mm. The result shows that limestone dust has water-reduce effect and does not reduce the strength of the mortar when the dosage of limestone dust is less than 12%. Meanwhile the addition of limestone powder can improve the shrinkage property and the durability of sulfate. It explains that limestone dust has a certain activity, not the inert material.

Abstract: Plant fiber concrete in the cement base material (cement, mortar or concrete) to join the natural plant fiber, to form a new type of concrete, its advantages can improve the performance of concrete, concrete to reduce costs, save energy. Understanding straw fibers mixed with concrete, the variation in performance, with the same concrete than different content, physical and mechanical properties of the different shapes straw fiber concrete test analysis of the concrete compressive strength, splitting the variation of tensile strength, flexural strength, and economic aspects of performance, to provide a reference for further study of the straw fiber reinforced concrete and other performance and application.