Advanced Materials Research Vols. 671-674

Abstract: The complete stress-strain curves of recycled aggregate concrete with different recycled coarse aggregate replacement percentages were tested and investigated. An analysis was made of the influence of varying recycled coarse aggregate contents on the complete stress-strain curve, peak stress, peak strain and elastic modulus etc. The elastic modulus of RC is lower than natural concrete (NC), and with the recycled coarse aggregate contents increase, it reduces. While with the increase of water-cement ratio (W/C), recycled concrete compressive strength and elastic modulus improve significantly. In addition, put forward a new equation on the relationship between Ec and fcu of the RC.

Abstract: For an infrastructure construction located in marine environments, maintaining good durability for the structures always imposes serious challenges, especially for the structure made of reinforced concrete. Concrete exposed to marine environment may deteriorate as a result of combined effects of both physical and chemical actions from marine environment. Corrosion of the reinforced steel bars that are embedded in the concrete is the most serious problem. Therefore, a method to protect the reinforced concrete in the marine environment from damages due to material deterioration and corrosion is proposed in this study. The method is through the application of bentonite material by utilizing its very finely divided form so that the larger capillary pores in concrete can be filled up. In this way, the impermeability of concrete material can be enhanced and then improve the corrosion resistant ability of the material.

Abstract: With development of concrete technology, the self-compaction concrete, as a green material, has been studied and widely applied thanks to its characteristics like self-leveling, self-compacting and desirable fillability. At present, high performance and ultra-high performance is an important trend in development of self-compaction concrete technology. Working performance, physical performance, endurance quality, ultra-high pumpability and microstructure of C100UHP-SCC are studied in this paper. The initial fluidity of studied UHP-SCC reaches above 550mm and maintains for 3h without loss, its compressive strength on 28d is more than 100MPa, which can ensure the architectural structure to last for 100 years and enable ultra-high pumping over 400m. The technical parameters mentioned above provide valuable reference for design and construction of super high-rise buildings which are above 1000m.

Abstract: Fabricated straw brick is a new wall material, its character is a kind of sandwich structure with tenon and groove, and wall assembly does not require any additional connections. Experiment and calculation have done to study the thermal parameters of fabricated straw brick and environmental protection performance of building in this material. The results show that straw wall’s heat transfer coefficient is much lower than that of normal concrete block and lightweight aggregate concrete block, which can guarantee good insulation performance. It was proved to have good thermal insulation in the further computational analysis. Therefore, it is a kind of environmental protection building material.

Abstract: Gaomiaozi (GMZ) bentonite has been chosen as a matrix material of buffer/backfill materials in the deep geological disposal to isolate the high level radioactive waste in China. Swelling characteristics of GMZ bentonite and its mixtures with sand wetted with water were studied by experimental methods. The tests result shows that the relation between void ratio and the swelling pressure of compacted GMZ bentonite-sand mixtures at full saturation is independent on the initial conditions such as initial dry density and water content, and dependent on the ratio of bentonite to sand. An empirical equation is proposed to predict the swelling deformation and pressure of the mixtures with different densities and bentonite/sand ratios.

Abstract: In order to get mechanical properties ,some RPC samples with 5% steel fiber are tested, many groups data were obtained such as compressive strength, shear strength and fracture toughness. And a group of tests on RPC with 5% steel-fiber under penetration were also conducted to validate the performance to impact. The penetration tests are carried out by the semi-AP projectiles with the diameter of 57 mm and earth penetrators with the diameter of 80 mm, and velocities of the two kinds of projectiles are 300～600 m/s and 800～900 m/s, respectively. By contrast between the experimental data and the calculation results of C30 reinforced concrete by using experiential formula under penetration, it shows that the resistance of steel-fiber RPC to penetration is 3 times as that of general C30 reinforced concrete.

Abstract: Timber, a traditional construction material that was almost forgotten. Timber structure building got a qualitative leap in structure form, mechanized producing craftmanship and matching products, along with social progress and technology improvement. This paper will summarize modern timber structure forms by comparison with popular constructional material, like concrete and steel, in five aspects including life-cycle energy consumption, structure form, construction cost, construction period, seismic performance. Timber's advantages and disadvantages in architectural design will be listed, which may provide theoretical basis for diversified choice of construction materials in architectural design.

Abstract: Infra-red thermography is widely utilised in the restoration of buildings. This article presents a novel method in the application of thermography to the analysis of rammed earth walls, and the Valencian rammed earth wall, or tapia valenciana, in particular. For this study, the authors chose The Colegio de Corpus Christi de Valencia (Spain). First, an analysis of costs incurred during the construction of the Colegio (built 1586-1610) was carried out. Second, thermographic techniques were utilised to gather further data on its construction process and corroborate information appearing in historical records. The rammed earth walls of this large building rest upon a stone footing. This study proposes a methodology that can be extensively applied to other similar studies with a view to understanding construction processes.

Abstract: This paper presents the studies on surface contact angles of water and phenolic resin and bonding strengths of three kinds of radial bamboo strips and chordwise bamboo strips. The results showed: water and phenolic resin could better wet radial bamboo strips, and wettability and gluing properties of the base radial bamboo strips were best, the middle radial bamboo strips followed, the tip radial bamboo strips ranked third in the three kinds of radial bamboo strips; wettability of water and phenolic resin and gluing properties of chordwise bamboo strips were better than radial bamboo strips.

Abstract: Polymer epoxy resin is widely used in coatings and adhesives because of its excellent mechanical properties, adhesive properties, resistance to water and resistance to chemicals. In this paper, the research development status of the epoxy resin coating in building waterproof is reviewed. The preparation, performance measurement and application of epoxy resin waterproof coating are introduced, and the development trend of building waterproof coating is forecasted.