Applied Mechanics and Materials Vol. 470

Abstract: The objective of the survey which was conducted in the Klang Valley of Malaysia was to prioritise factors that are considered by building contractors in estimating the construction cost of buildings. Respondents selected by simple random sampling have been asked to assign a one-to-five rating for each of the total of 79 cost factors identified from the literature review. The result of the preliminary survey of factors influencing project cost estimating practice of building contractors has indicated that only 35 cost factors have been regarded by the respondents from small, medium and large building construction companies as highly relevant for building construction projects. ‘Client requirements on quality’ was found to be the most significant cost factor influencing the construction cost of buildings.

Abstract: As the progress of theory and computer technology, nonlinear analysis is widely applied in civil engineering. Strip method, as one of the numerical methods, is used widely especially in the analysis of beams, columns and shell structures. The first half of this paper introduces the theoretical model and the basic assumptions of the strip method; the latter half of this paper compiles the strip method into computer program using FORTRAN language. At last, using beams with rectangular cross-section of reinforced concrete structures as an example, the paper analyze the factors, such as the strength of the steel bars, which have an impact on the bearing capacity of reinforced concrete structures.

Abstract: Water-rich and soft fault fracture zone is the geologic disaster source of water and mud outbursts in tunnel while the curtain grouting is an effective management method. To determine appropriate parameters of the grouting reinforced circle, depending on fluid-solid coupling theory and numerical simulation of the seepage fieldstress field, the influence of parameters to the water inflow and stability is analyzed while grouting effect was evaluated from the two aspects of reinforcement and water plugging. The conclusion show: the permeabilitystrength and thickness of the grouting reinforced circle are important factors of water inflow and surrounding stability while the choice of the thickness is inflected by the permeability and strength, when which reached a certain value the minimum thickness of the grouting reinforced circle is gotten.

Abstract: CRTS II ballastless track slab tend to generate vertical deformation when filling cement asphalt mortar. The phenomenon mentioned above leads to higher probability of generating joints between track plate and cement asphalt mortar. Based on the finite element theory, a mechanical model that contains track plate, supporting slab, cement emulsified asphalt mortar and withhold device is established. The purpose of such a model is to research the interaction among components as well as simulate the exact CRTSIIballastless track structure. By analyzing the influences of various trackway conditions, cement asphalt mortars filling height and withhold device arrangement on vertical differential deformation of track plate, put forward the measures to restrain the vertical deformation of track plate. The research results provide references for the ongoing ballastless track construction on the Shanghai-Kunming passenger dedicated line.

Abstract: In this study the three dimensional finite element method is employed to analyze the time history response for the service bridge pier of a water release integrated structure under the minimum operation level and the normal storage water level in maximum design earthquake load condition. The Mexico seismic curve is provided to perform the time history analysis for the present project. The temporal integration of time history analysis is carried out by the Newmark method and the stress, deformation results of the service bridge pier structure is discussed in detail.

Abstract: The stress, deformation and stability for the intake tower of a water release integrated structure under the normal storage water level and operational basis earthquake load case are investigated using the three dimensional finite element method. The response spectrum analysis is adopted to study the seismic response of the intake tower. Special attention is paid to the weak zones of the structure and foundation. The safety evaluation of the intake tower is performed based on the computational results.

Abstract: Based on the solution of one-dimensional consolidation model of T-shaped bidirectional soil-cement deep mixing column composite foundation and its calculating program deduced by the separation of variables and Laplace method. This paper discussed the consolidation and settlement characteristics of composite foundation under the conditions of different loading modes, foundation reinforcement modes, diameter of enlarged pile head and pile spacing. The results indicate, the soil layer in the region of enlarged pile head hardly be influenced by above factors, the lower soil layer and soft substratum soil are influenced greatly. Loading mode has a large effect on the consolidation, when loading instantaneously, the rate of consolidation is faster than that of loading constantly. The consolidation and settlement behavior of composite foundation reinforced by T-shaped bidirectional soil-cement deep mixing column and traditional bidirectional deep mixing column is much better than the original natural foundation. When the other parameters stay the same, consolidation degree and total settlement decrease with the increase of enlarged pile head diameter. With the increase of pile spacing, consolidation rate of the composite foundation decreases significantly, but the settlement value increases rapidly on the contrary.

Abstract: In Part I, to have an environmental-friendly, highly durable, cost saving, and easily constructible method in top-down construction, one prototype of a joint of PHC pile to column was suggested on the basis of analytical studies. In this paper, structural performance of such joint of PHC pile to column is experimentally analyzed with regard to axial strength and strains.

Abstract: Abstract: West Slope Tunnel's surrounding rock is broken. A positive step method is used in the reconstruction process of collapsed West Slope Tunnel. During tunnel construction process, heavy rain cause a landslide failure of tunnel (Located in DK51+175- DK51+195). The mainly collapsed area is located in the position of DK51+180. According to collapsing, we executed the settlement observation, cross-section deformation detection and upper crack observation.When collapse settlement is basically stable, the collapse is segmented to settle. The previous board of Secondary lining for the collapse need to add steel reinforcement and tunnel collapse cavity backfill C30 concrete. When concrete strength is expected ,it need to be excavated and must keep the core soil. The advanced small pipe is needed to stabilize the soil before the excavation section. In invasion of secondary lining collapse, girdle previous Primary Support and reform Primary Support.. Add I16 steel frame where necessary. We must strengthen the tunnel monitoring to ensure the safety during tunnel construction process.

Abstract: To overcome disadvantages of usual Cast-In-Place (CIP) concrete pile methods in top-down construction, some prototypes of a joint of the PHC pile to column that directly connects a column to a PHC pile are analytically studied. With the consideration of strength requirement and stress concentration of joint of the PHC pile to column, we suggest the most appropriate one.