Advanced Materials Research Vols. 368-373

Abstract: As a significant tool in architecture design nowadays,the diagram’s development has gone through a long history.In recent years,the developing of diagram theories make architects pay more attention to the relationship between the diagram and architecture design.This text introduces the development of the diagram in architecture design briefly and discuss the mechanism of the diagram works in an architect design process elaborate.The forth part of the text introduces the new technique’s application in the diagram.

Abstract: The static load test of 34 jacked-in PHC pipe piles of medium length are performed in the cohesive soil area, the relationship between the vertical ultimate bearing capacity and the final pressure, and the time effect of vertical bearing capacity of the jacked-in PHC pipe pile are studied. The data of static load test is analyzed statistically with software SPSS, the regional empirical coefficient about the vertical ultimate bearing capacity and final pressure, and the time effect formula about vertical bearing capacity of the jacked-in PHC pipe pile in the cohesive area are obtained. According to the regional empirical coefficient, the pile pressing machine and counterweight can be chosen reasonably and the vertical ultimate bearing capacity of single pile can also be estimated rapidly, then we can instruct the design and construction of the jacked-in PHC pipe pile. According to the time effect formula, the vertical bearing capacity at different periods of the jacked-in PHC pipe pile can be obtained, the cost of the foundation engineering can be reduced by considering the time effect influence to the vertical bearing capacity of the jacked-in PHC pipe pile.

Abstract: In more and more complicated urban building environment, a new construction method that metro engineering is constructed by large-diameter shield and shallow mining method can be regarded as a great attempt in China. By taking the Gaojiayuan station of Beijing metro line 14 as an engineering background, the main construction steps for the platform of the metro station built by a large-size shield with an outer diameter of 10 m and the Pile-Beam-Arch (PBA) method are introduced. Based on the soil-structure interaction theory, a two-dimensional finite element model is used to simulate the shield tunneling and the platform construction by the PBA method to enlarge the shield tunnel. The ground deformation and structural stress of the platform are predicted. The numerical results can be regarded as a valuable reference for the application of the new construction method in Beijing metro line 14.

Abstract: On conditions of different weight，height, shape and the property of slope surface, the tunnel portal structure’s deformation evoked by rock-fall impaction has been researched in laboratory by using a 1/30 scale similar model. The study shows that there is a simple linear relationship between the structure’s deformation , the rock weight and the rockfall height when the slope gradient is 1:0.5 and the slope surface is slippery and the multiple linear relationship between the structure’s deformation , the rock weight and the rockfall height has been obtained. Effect of the shape of the rockfall and the property of slope surface on structure’s deformation has been comparative analyzed.

Abstract: According to the characteristics of installation about the penetrometer of seismic piezocone penetration tests (SCPTu) and the pile, a theoretical relationship between ultimate bearing capacity of single pile, time-effect of shaft bearing capacity of single pile, excess pore water pressure around the pile during pile driven and the data measured from SCPTu is developed based on the cavity expanded theory, the Terzaghi one-dimensional consolidation theory and effective stress theory. The result of field test in KunShan and the calculated result which used the theoretical relationship mentioned above are compared. The results indicate that the analytical solutions agree well with the in-situ tests, which show that the application of seismic piezocone penetration tests have wide range in the pile foundation.

Abstract: With the speedy development of Beijing mass transit, the land for metro engineering construction is becoming more and more insufficient; moreover, more and more complicated building environment problems are coming forth in future. In a complex building environment, how to choose available construction method to fast, safely and economically build metro engineering is worthy to be urgently studied in Beijing mass transit. Taking the experiment project of Beijing metro line No.14 as an engineering background, a new construction method that a running tunnel is firstly built by large-size shield method and then a metro station is constructed by shallow mining method to enlarge existing large-diameter shield tunnel is presented in this paper. Based on the building conditions of the experiment project, three architectural design schemes for the metro station and two kinds of construction plans are briefly introduced, and their advantages and disadvantages are analyzed as well. The new construction method can be used as a reference for the design and construction of metro engineering in China in the future.

Abstract: The mechanism of gas outburst, gas-solid coupled simulation by discrete element method and natural gas problems in the Yuanliangshan tunnel are studied. Petroleum gas and coal gas are produces in the karst region generally; gas outburst includes coal gas outburst and the petroleum gas outburst in the tunnel construction. Gas migration mechanism and mathematics model, including macroscopic and microcosmic mechanism, migration mathematics model, diffusion models, and gas-solid coupled discrete element method (DEM) numerical simulation of gas migration and mechanism of gas outburst are proposed. Based on the methods above-mentioned and monitoring data, some import problems are studied, such as natural gas storaging character in the entry of Yuanliangshan tunnel, forecast methods of natural gas, relation of natural gas and underground water, kinds of poisonous and harmful gas and its appraising, evaluation indexes of air quality in tunnel, etc.

Abstract: Based on the single-phase elastic soil medium control equations and boundary conditions [1], by using the weighted residual method, a semi-analytical theory of elastic foundation three-dimensional static response was established. When the uniformly distributed loads were applied on the elastic half space foundation, the change rules of vertical displacement, lateral displacement, lengthways displacement were analyzed numerically, and compared with the theoretical solution [2]. The result shows that foundation displacements are completely symmetrical or antisymmetrical about x = 0 plane and y = 0 plane. The maximum vertical displacement appears in the center of load range, the maximum lateral and lengthways displacements appear at the edge of load range, and the displacements get smaller far from the loads.

Abstract: The internal force and deformation of shield tunnel segment lining are influenced by many kinds of characteristic parameters. By the elastic foundation circle method, this paper takes the example of the first phase of the project of the Shenyang metro line 2, analyzing the influence of each characteristic parameter on internal force and deformation of the lining, and summarizing rules for the design of shield tunnel lining.

Abstract: Though the test level has improved highly, the original grading curve of coarse materials should be reduced in some scale in dynamic triaxial test. This method must affect the difference between the test results and the real results, which is called scale effect. In this paper, the scale effect was studied by using particle flow code (PFC) based on dynamic triaxial tests. The relationship between microscopic shear modulus and the maximum particle diameter can be simulated by hyperbolic function. The results show that the dynamic shear modulus and damping ratio are increased with the sample size increase. The normalized dynamic shear modulus vs. normalized dynamic shear strains of different size samples are located in a narrow space which can be simulated by modified Hardin-Drnevich model formula. The parameters of maximum shear modulus and damping ratio of different sample size can be simulated by power functions.