Advanced Materials Research Vols. 168-170

Abstract: The chloride permeability of concrete with slag or (20wt%, 30wt%, and 40wt% of binder) and binary slag and fly ash (the ratio of slag and fly ash 5:5, 4:6 and 6:4) was investigated in this study. The results show that the chloride permeability of concrete decreases firstly and increases latterly with the increasing of fly ash content. However, the permeability of concrete with slag decreases sharply with the slag content increases. Especially the content of slag is 40 wt%, the permeability is only 15.4% of the control concrete. The permeability of concrete using binary admixture of slag and fly ash is less than that of fly ash concrete and more than that of slag concrete.

Abstract: Mechanical behavior of Styropor concrete(EPSC) added with various volumetric fractions of EPS subjected to high strain rates were studied by using the Large-Diameter-SHPB. The infection of volumetric fractions and average strain rate to dynamic properties of EPSC were investigated. The experimental results show that under high strain rate condition, the dynamic strength, dynamic strength increase factor(DIF) and limit strain of EPSC are strain rate dependent, the strain rate effect can be expressed by linear approximations, and the relationship between elastic modulus and average strain rate is independent.With the addition of volumetric fractions of EPS, the impact compressive strength and elastic modulus of EPSC declines, and the toughness of EPSC is reinforced.

Abstract: Based on the experiment of four brick masonry walls under low-cyclic lateral loading, the effectiveness of the method of using the continuous carbon fiber sheet(CFS) and steel-meshed cement mortar to strengthen the brick masonry walls for improving their aseismatic performance is studied. The failure mechanism and aseismatic behavior of the walls are analyzed. Finally, the destructive mode, load bearing capacity, deformation, hysteresis characteristics and ductility are also analyzed qualitatively for the individual wall.

Abstract: Based on counter magnetostriction effect the magnetization intensity and stress sensitivity was analyzed for ferromagnetic material. The stress sensitivity of magnetized material was discussed on basis of the law of minimum energy and movement of magnetic domain structure. In accordance with the effect of magnetization intensity from stress the applied stress can lead to movement of domain wall of magnetic domain in the demagnetizing state for ferromagnetic material when the net magnetic moment is equal to zero. Meanwhile easily magnetization axis can be established on known applied stress. Then when ferromagnetic material is forced by the applied stress the magnetization intensity can be changed obviously. It is happened so that magnetic flux is also changed simultaneously. The result shows that real-time strained condition of material can be judged on basis of testing change of magnetic flux. Furthermore the study theory of magnetic nondestructive testing of defect sensibility structure for long span steel structural is obtained through this analysis.

Abstract: This study aimed at evaluating the physical, mechanical and thermal properties of a structural laminated veneer lumber(LVL) prepared with self-made fire-retardant NSCFR being applied to the adhesive. Cone calorimeter(CONE), thermogravimetry(TG-DTG) and universal testing machine were utilized to assess the performances. Results showed that: fire-resistant and smoke-suppression characteristics of the fire-retardant treated LVL (FRLVL)were satisfactory. The heat release rate(HRR) of it was smaller than that of the untreated wood and it did not exhibit the typical second pkHRR of wood-based materials. It had a residual mass rate of 33.32% after exposure to fire. Overall production rate of CO and CO2, average specific extinction area and average smoke rate for it were remarkably less than that of unprocessed wood. In addition, FRLVL possesses acceptable physical and mechanical properties. It showed higher density and lower thickness swell after 24h water immersion than the control group and the strength parallel to glue-line parameters in static bending----modulus of rupture(MOR), modulus of elasticity(MOE), shear strength(SS) were 38.698 Mpa ,6.376 GPa and 4.389MPa separately, all of which met the corresponding requirements for structural LVL specified in the China National Standard GB/T 20241-2006.

Abstract: This article (Part-II) continues the work of a previous article (Part-I). It undertakes a theoretical analysis of the curvature ductility factor (CDF) of a singly reinforced CRC (crumb rubber concrete) beam and demonstrates how CRC’s material ductility is transformed into structural ductility of a reinforced CRC beam. The result shows that CDF for a reinforced CRC beam is much higher than that for a conventional concrete reinforced beam.

Abstract: The effect of water-cement ratio, air content, silica fume and sand ratio of concrete on the coefficient of linear expansion(CLE) was studied by orthogonal experiment. The results show that under a certain amount of cement material, CLE of concrete increase as the water-cement ratio increases and the effect of water-cement ratio on CLE of concrete is remarkable; with the increase of blending ratio of silica fume, the CLE of concrete increases; the CLE of concrete reduces with 3.5% air content in concrete, but rebound with 6% air content in concrete; with the sand rate increases, CLE of concrete increases; CLE per unit compressive strength of concrete with silica fume decreases with increase of silica fume content; CLE per unit compressive strength of concrete with air content increase when air content increase.

Abstract: Along with developing at top speed of city construction, building energy consnmption rises substantially,and the huge building energy consnmption has been became heavy relieve of economic social development.In the realm of superstructure, specially in the building design link, conserve energy overall has great significance.The paper mainly discuss about energy conservation design of regional space integration or external environment, energy conservation design of building monomer,and new energy-efficient technology or material for energy saving application in building design,and so on.

Abstract: FRP (Fiber Reinforced Plastics) has been suggested as alternatives to steel reinforcement of buildings in corrosive area. In this paper, a new CFRP rod having U-anchor for connection and manufacturing machine of it are reported. With the developed machine, carbon fiber bands were assembled under constant tension carefully, and U-anchor CFRP rods were manufactured experimentally. Tensile test of the CFRP rods was performed, and U-anchor part was found to have enough strength to connect CFRP rods.

Abstract: In order to effective utilize of recycled fine aggregate concrete (RFAC), it is necessary to clearly understand its behavior and characteristic. In this paper, experimental study on crack behavior of RFAC was conducted with different curing ages. Ratio of its cracking load to ultimate load was analyzed in detail. Experiment shows that this ratio is about 0.8 and is not sensitive to curing age. Comparison to traditional concrete was performed. The result of this paper is helpful to theoretical analysis and practical engineering design of RAC structures.