Advanced Materials Research Vols. 690-693

Abstract: The aim of this paper is to investigate the serviceability performance of RC beams strengthened through two Ferrocement strengthening techniques as Cast in situ Wire-mesh layers and precast Ferrocement Laminates. To assess the effectiveness of these strengthening techniques, eight (08) RC beams have been intentionally designed and detailed as a tension-controlled section and tested under two-point loading up to service load of 40 kN. Then, beams were strengthened by Cast in situ Wire-mesh layers and by precast Ferrocement Laminates. Experimental results in terms of stiffness have been compared within and across the groups to assess the effect of variation of development length and no. of wire-mesh layers.

Abstract: This paper mainly focuses on the actual situation of reconstruction works on provincial highway 310, 311, 104 line from Yuanyang to Wuzhi sector (to be up State Road), and analyses the pavement disease and the cause of it in different sections, different pavements structure, different traffic environment, as well as proposes to take measures to prevent the pavement disease, combines with conservation work in highway construction and practice in this area.

Abstract: To realize axial load behavior of CFDST, ANSYS is used to analyze the process from load to destruction that hollow section ratio is the main variable parameter. To explore the validity of finite element analysis software, axial compressive strength is calculated combined with formulas of existing criterions. The results show the finite element results have a good agreement with text values and calculation.

Abstract: The foamed cement paste (FCP) is a kind of inorganic insulation material. It is characterized by its light weight, heat-insulating and fire-proofing properties, and the thermal conductivity is close to that of expanded polystyrene (EPS). The foamed cement paste is achieved by means of chemical reaction. The mixture proportion, the preparation process, mechanical and thermal properties are investigated in this paper. The results show that properly mixed paste foams stably, and the bulk density could be controlled. The hardened FCP could be used as insulating filler material in composite walls, as well as blocks for Thermal insulation walls.

Abstract: Low-carbon economy is the only way for China’s economic development, and also an important part of achieving the commitment to the world about reducing 40-45% carbon-emission until the year of 2020. In recent years, the increasing speed of hotels in China has become higher and higher, but most hotels have the problems of serious waste and pollution. This doesn’t benefit for development of low-carbon economy in China. So building low-carbon hotels is imminent at present. From the perspective of circular economy, this paper analyzes the ubiquitous problems in the process of building low-carbon hotels, and then summarizes successful experience of building low-carbon hotels in foreign countries. Finally, the paper put forwards to corresponding countermeasures of building low-carbon hotels from four aspects including policy, technology, culture and behavior.

Abstract: The foundation of A tower of Hongyun building is made of raft board foundation which is 4200mm in the thickness and 3500mm beside side of the core tube. It is researched that the raft foundation mass concrete construction technology is expatiated from temperature and cracks of the raft foundation and the temperature control and monitoring of the concrete base slab construction and concrete curing.

Abstract: The general concepts of two basic forms of deflection are summarized and the existing calculation theories of deflection are introduced; two cases of concrete structure deflection, which are short-and long-term deflection, are discussed through comparison. Further, the basic theories of deflection calculation and deflection control methods are indicated based on two different cases in this paper.

Abstract: The bearing capacity formula of concrete filled thin-walled steel tubular (CFTST) short column was established based on limit equilibrium method, and the reasonable value for k₁ in Richart Strength Model was regression introduced adapted with concrete stress-strain relations. According to the elasticity modulus theory, the calculation formulas of stability bearing capacity of CFTST slender column were deduced, reasonable considering the interactions between steel tube and concrete. And the calculation process is relatively simple which avoiding complicated iterations used in the conventional calculation method. Finally, the comparative evaluation on calculation formula was done based on 79 groups of test results of concrete filled steel tubular column at home and abroad. Results of calculation formula agree well with the test results in safe range.

Abstract: Magnesium slag was used to produce cement clinker replacing part of limestone and sandstone with 11% content. The results show that the magnesium slag can significantly improve the grindability and burnability of Portland cement raw materials. The 28d compressive strength of this clinker is 58.9MPa and the physical performance can satisfied the requirements of 52.5 strength grade according to GB 175-2007.

Abstract: The expressions of crack spacing and width were deduced from the aspect of force-balance. The concept of maximum spacing and width of crack were put forward accordingly and they were verified and consistent with the site test results. Their relationships with soil parameters were discussed in detail. The new cracks do not appear until the spacing of adjacent cracks is greater than the maximum spacing, and the width of cracks will not be greater than the maximum width. The maximum spacing and width are judgments for describing and represent the final characteristic of cracks due to evaporation.