Abstract: Nowadays, globalization is gradually sweeping across the world, and the traditional cultural context of the city receives unprecedented impact, the urban characteristics are gradually disappearing and there appears to be the phenomenon of “thousand cities with one face”. In such circumstances, looking through the cultural traditions of the nation, inheriting the cultural context of the city and keeping its own cultural independence and the urban characteristics have been an important issue concerned by the countries. This text takes Nanjing as an example to research on the culture of the city under the regional background from the aspects of geography, culture, economy, society and so on along the historical context. On this basis, there is also a discussion about constructing the system of urban characteristics of Nanjing, underlying causes of and approaches to deal with the the characteristics crisis of current Nanjing City.
Abstract: The failure process for an extra-long pre-stressed concrete beam under static loads was simulated based on the elastic damage theory with the commercial software ABAQUS. By taking account of the different damage behaviors of concrete under tension and compression conditions, a damage mechanics model with three independent parameters was derived from the elastic damage theory. By combining the proposed damage model with the ABAQUS, the damage model was added to UMAT user subroutine. This method was developed to analyze the failure process of the extra-long pre-stressed concrete beams. The theoretical results show that the proposed damage constitutive model can be applied to describe the damage and fracture behaviors of the extra-long pre-stressed concrete beams.
Abstract: Real estate Industry is capital-intensive. Cost management is very important for real estate. Efficient cost management is one of important means that can ensure sustainable development of the real estate business. Now, we must find out the efficient cost management means according to analysis the importance of the real estate and the problem exist in it.
Abstract: With the development of urban construction, deep large pits are often located at intensive underground structure area, and the utility pipe tunnel within various pipelines is the lifeline engineering of urban environment .Thus, there is the very necessary practical significance to research on utility pipe tunnel influenced by adjacent deep Excavation. Using large finite element software ANSYS, we analysis the problem with the deep foundation pit, support system, the soil around and adjacent tubes as an entirety. In considering of the mutual interaction between support structure and soil, as well as the element birth-death technology and restart analysis technology, the deep foundation pit mode is simulated and analyzed according to the actual construction process, including the gravity initial stress analysis and the simulation analysis on the each layer soil excavation. After simulation analysis the level of utility pipe tunnel’s horizontal and vertical displacement environment in different affecting factors and reinforcement measures, it is concluded that the law of utility pipe tunnel’s horizontal and vertical displacement, further the reasonable economic measure is put forward to protect the safety of the utility pipe tunnel. Therefore the conclusion has certain reference value for designing the foundation pit construction and the protection measures on the adjacent utility pipe tunnel.
Abstract: Based on two-parameter foundation model and Mindlin plate theory, the FEM equation for free vibration analysis of elastic plates resting on elastic foundation is derived by Hamilton variation principle. The effect of foundation beneath the plate is combined in the stiffness matrix of the plate element, and the effect of the foundation outside the plate domain is taken into account by boundary element method. By coupling FEM and BEM, numerical analyses for the free vibration of foundation plates are carried out. Calculated frequencies are in good agreement with measured results, which proves the accuracy and efficiency of the present approach.
Abstract: Based on the test data of shaking table tests of subway station structure in soft ground under both near-field and far-field earthquakes, the spatial effects of peak ground acceleration (PGA) of soft ground as well as peak strain response of the subway station structure are analyzed. The results show that the peak acceleration of measuring points on both major and minor planes increases with the growing peak acceleration of earthquake. The law of PGA and frequency spectral character of measuring points on different observation planes or at different depth varies with each other, and there presents remarkable spatial effect. The peak strain of central cylinders on the major plane appears larger than that on the minor planes. There are sharp contrasts among the peak strain responses in different spatial positions of the station structure.
Abstract: The mechanical impedance and the piezoelectric coupling impedance response spectrum, the resonant vibration mode and he resonance frequency of the cantilever beam was analyzed by means of FEA for getting the relationship between mechanical impedance and piezoelectric impedance. The results showed that: Through the comparison between the two, both resonance frequency and resonance modes are the same basically, which also showed that the change of piezoelectric impedance changes with the mechanical impedance change. Piezoelectric impedance is the electric reflection of mechanical impedance. It provides a sound theoretical basis and research methods for the piezoelectric impedance damage identification and health monitoring technology.
Abstract: Riprap concrete technology is the effective measures to control the temperature cracks in construction of mass concrete. But in the implementation process, there are some problems. In this paper, riprap concrete technology problems of the actual implementation are proposed, and the optimal solution is given. At last, relation to Dinghan gardens project raft foundation of mass concrete works, the material mix proportion is described in the paper. At the same time, construction technologies are outlined including pouring by segmentation and layer, riprap technology, bleeding treatment and concrete maintenance. The construction strength is tested by comparison test of normal maintenance. The results present that it not only solve construction problems of mass concrete in summer, but also shorten construction period and decrease construction cost.
Abstract: A 2D CFD numerical method based on loose coupling algorithms was adopted to simulate vortex induce vibration of a spring-mounted cylinder. As the accuracy and reliability were focused, the effect analysis of time-step was applied to three typical reduced velocities, which was represented initial branch, upper branch and lower branch respectively. Under the effective courant number, there exist a time-step which would lead to the highest efficiency and the best match for experiment. Because of the limit of RANS method, the predicted vibration amplitude at the upper branch would be lower than experiment value, while the phase angle is sensitive to time step.
Abstract: Concrete mortar powder body composition and the body of thick liquid to compound method, have analysed difference, match the property that takes off mortar than condition , have reached the best mortar that is more practical than project practice to compound method. The mortar that made can be applied extensively in project field.