Advanced Materials Research Vol. 790

Abstract: The concrete-filled steel tube structure possesses the advantages stemming from both steel and concrete. When the structure receives pressure, the concrete in the steel tube bears the stresses from three directions owing to the restriction of the steel tube. The structure does not only have high bearing capacity but also a good plastic property. Though the wall of the steel tube is thin, the local deformation of yielding can be prevented due to the presence of concrete in the tube. The combination of both materials can help conquer their respective weakness and bring their strong points into full play.Therefore the concrete-filled steel tube structure has a bright future. Whether a structure system has a bright future largely depends on the economic benefit of the system. This paper presents an economic analysis on concrete-filled steel tube structure by way of comparing the reinforced concrete structure.

Abstract: The paper adopts the interface element to simulate the joints so as to systematically and quantitatively study the deformation around tunnel, the mechanic state of lining and the stability under different inclining angles of joints. The result shows that the deformation around tunnel deteriorates mainly along the joint during the inner convergence effects of surrounding rock. When the inclining angle α=45°, the deformation around the tunnel is most serious, followed by that when α=90°, α=60°, α=30° and α=0°. At the same time, the influence of inclining angle on the distribution of the axial force of lining is comparatively small. But the distribution of bending moment and shear change obviously where the joints penetrate the tunnel. The tunnel stability of surrounding rock is the poorest when α=90° and the tunnel is most stable when α=0°. The stability of surrounding rock changes little when α is between 30° and 60°. The research result provides an effective calculation method for the forecast of deformation, the design of structure and the stability analysis of jointed tunnel. It is also helpful for the monitoring of construction and calculation of jointed tunnel in the future.

Abstract: In south China, residual soil is widely distributed and one of the most main soil in engineering construction at the coastal areas. While its mechanical characteristics are easily affected by moisture content, which is a serious threat to engineering stability and safety. In this paper, granite residual soil in a construction site of Xiamen is selected as remoulded specimens, and unconfined compressive strength test and static triaxial shear test are used, which will show the influence of moisture content (20%, 23% and 26%) on the mechanical properties of specimens. As the result is analyzed, it shows that mechanical properties such as stress-strain relationship, unconfined compression strength, internal cohesive force, internal friction angle, and shear strength, are better than other specimens when the moisture content is 23%, which will be beneficial to the stability and security of engineering soil.

Abstract: Accurate mechanics parameters are the precondition of reasonable calculation in the finite element method to calculate the deformation and stability of the rock mass engineering stability. Partition classification method can be used in the simulation of macro-mechanics parameters of rock mass, for the distribution of multiple sets of multi-level joint fissure in some engineering rock, the parameters of the rock mass can be simulated using the numerical method step by step or by group. Based on the partition classification method, the paper simulated the macro-mechanics parameters of natural slope upstream the left bank toe board of Maerdang hydropower station. The slope is divided into three areas according to the rock types and intensity, weathering degree, fracture, the trend and tendency of the fault, spacing and connected rate of the structure surface, the mechanics parameters of the structure surface, the groundwater conditions, and then use the partition classification method to calculate the region's macro-mechanical parameters, the results can be used to provide amount of reasonable parameters for the stability calculation of the slope in the subsequent deformation.

Abstract: [Objective] Research on city sewage sludge shale brick in the firing process of crack formation reason, control cracks in the firing process of the brick body, thereby improving the brick product quality, summed up the law of temperature on product quality of city sewage sludge shale brick.[Methods] In order to shale and city sludge as raw material by make bricks, drying and sintering procedure different, to analyze the reason of brick in the process of drying cracks and cracks during the roasting process.[Results] The experimental results show that in the stage of drying and preheating stage if rising too quickly, the sharp increase in the number of brick cracks, resulting in a significant decline in the quality of the finished brick. During the cooling phase if the cooling too quickly, also will increase the number of cracks, leading to reduced quality of brick.[Conclusion] Have an important influence on city sewage sludge shale formation temperature cracks, the control of the temperature is not only reasonable will prevent the formation of crack, but also an effective means to improve the quality of protection brick.

Abstract: At present, self-cleaning architectural coatings is one of important type of specific function coatings. Those play an important role in protecting and decorating the buildings. Research progress of self-cleaning architectural coatings was reviewed in this paper.

Abstract: The fundamental frequency is the inherent attribute that describes the structural mechanical property of rigid pavement. A finite element model of 45 m x 15 m x 11 m is given by means of the ANSYS software. With the method of modal analysis, the pavements structure was analyzed with 8 different thickness of surface course, 6 kinds of modulus of surface course, 5 different thickness of base course, 5 kinds of modulus of base course, 5 different thickness of subgrade and 8 kinds of modulus of subgrade, and correspondingly, the fundamental frequency was calculated . The results show that thickness and modulus of surface course, thickness and modulus of base course have less effect on fundamental frequency, which decreases with increase of modulus of subgrade, but increases linearly with the growth of thickness of subgrade, these two factors have the main influence to the fundamental frequency. The research provides the theory basis and reference to the detection of the pavement in airports.

Abstract: Based on the theory and practice of existing composite foundation, this paper discussed the design idea and introduced the bearing capacity and deformation calculation method of the long-short-pile composite foundation. And it verified the feasibility of this method by engineering example. The results show that: the CM long-short-pile composite foundation which can effectively improve the bearing capacity, reduce the building settlement and differential settlement, and fully exert the potential of soil between piles, has theoretical research and engineering application value.

Abstract: A test of bending resistance and reinforcement is carried out on RC beams reinforced by applying sheet of glass fiber reinforced plastics (GFRP). A study and analysis is given to the traits of bending and rupture of RC beams reinforced by applying GFRP and to the effect of GFRP on ultimate bearing capacity and stiffness of the beams. The strengthening effect is investigated to give guidance in practice work.

Abstract: Steel single rib box section arch bridge is established on the basis of secondary development using parametric language of large-scale finite element software ANSYS. On the premise of same sectional area A of arch rib,height breadth ratio h/b is changed, and both the spatial instability mode under the condition of arch bridges dead weight and the stability safety coefficient under the condition of the first step instability mode is calculated. With the aim to optimize distribution of stiffness and stability of single rib arch bridge, the target is to find out a height breadth ratio h/b which can make in-plane and out-plane instability mode coupling, that is to say, equivalent stiffness of in-plane and out-plane of the mode.