Advanced Materials Research Vols. 446-449

Abstract: The actual project—the Bird Island Park in Shenyang, an example of hinge joint concrete block revetment ,using the FLAC analysis software, and the finite difference method percolation theory to calculate the 29 slope angle the role of a 45kg block under the action of the seepage stability of the slope. Variation in water head discussed in further detail and the role of the different blocks on the slope stability of the quality of the impact of the slope to provide a reference design and application.

Abstract: Earth pressure may change with retaining wall deformation in the process of deep excavating. But how The answer can be very important to the safety of retaining system. Using monitoring data of north anchor foundation pit of Runyang suspension bridge, this paper studied retaining structure and soil interaction. Find the relationship between retaining wall deformation and earth pressure in deep excavation. In this case, earth pressure increased with wall deformation upward the depth of 18m and decreased with wall deformation down below. A regression equation about foundation pit depth and ratio of earth pressure and wall deformation was established. Then give a simplified earth pressure calculation method considering retaining wall deformation.

Abstract: This paper studies the dynamic response characteristics of broken stone fills. Numerical simulation and in-situ test of the acceleration and settlement of a high fill under dynamic consolidation are carried out. The result shows that increasing compact energy and the compact numbers can improve the reinforcement effect. There is no significant relationship between the dynamic compaction number reaching the stable settlement and compact energy. When the compact energy is the same, compaction with a heavier hammer is better than compaction with a lighter hammer.

Abstract: The electromagnetic characteristics of rock and ore play an important role in resources, engineering and environmental fields. The high frequency part of rock electrochemical impedance spectroscopy can reveal its crack characteristics according to the test results and rock physical model and equivalent circuit. The mathematical foundation of high frequency part of rock electrochemical impedance spectroscopy is studied, and the ideal Nyquist figure is obtained from that, and the response characteristics of rock electrochemical impedance spectroscopy volume arc are been proofed. It provides the theory basis for further study rock electrochemical detection technology.

Abstract: Through the undrained dynamic triaxial experiment, the deformation characteristics of saturated soft clay under cyclic loading are investigated. The cyclic loading was simplified as sine wave. It is found that under different dynamic stress, the deformation patterns of specimen in this experiment can be divided into three kinds, such as dense compressed, tensile break-up and shear failure type. In the process of vibration, the deformation forms of samples can also be divided into three types by dynamic stress amplitude, such as stable, destructive and critical type. The dynamic stress amplitude corresponding to the critical type is called critical dynamic stress. With the dynamic elastic strain increasing gradually, the dynamic elastic modulus decreases and rigidity softening occurs. Furthermore, dynamic elastic modulus and dynamic elastic strain curve decrease while the cyclic number is increasing. Finally, to establish the equation of the relationship between dynamic elastic modulus and dynamic elastic strain, the factor of cycle number should be considered.

Abstract: The equation of motion for the coupled system of structure—MR-TLCD is formulated by Lagrange equations in this paper. Wind load response of a single-degree-of-freedom structure with MR-TLCD is obtained by time domain method. From the point of view energy dissipation force of MR-TLCD, the Simple Bi-State (SBS) control algorithm control algorithm is developed based on energy dissipation. By applying semi-active and passive control strategies, the controlled wind load response of the coupled system excited by wind load are numerically simulated. The peak value and root mean square value of the displacement and acceleration are obtained and the control effects of the system using the SBS algorithms. The results showed that the wind load responses of the coupled systems could be controlled effectively by applying the MR-TLCD.

Abstract: MMP pile is a method of foundation treatment, and driving pile brings the excess pore water pressure in the surrounding subgrade. By using a software ABAQUS to build a three-dimensional model, the process of MMP pile driven at a site of railway foundation in Shanghai is simulated using theory of Biot consolidation and modified Cam-clay model with three-dimension effect being considered. The changes in the excess pore pressure are obtained. Comparing the computed results with measured results in situ shows that the computed excess pore water pressure is consistency with that measured from in situ.

Abstract: Being the research object,the index of energy momentary change rate for sliding base-isolated structure is put forward and its corresponding design formulas are given，and three indexes of energy momentary change rate for sliding base-isolated structure including input energy,restorable energy of superstructure and friction energy dissipation on different level friction coefficient are analyzed numerically from the angle of energy.Research shows that energy momentary change rate is a very effective index for energy analysis of sliding base-isolated structure,and there are big relations between the index and isolation layer’s friction coefficient,and the index can reflect well momentary changes of all kinds of energy for every moment.

Abstract: The optimal design theory of the post-processing technology of thick filling area is based on the characteristics of small non-sand concrete pile, to research the production and development process of stress and strain of foundation soil in the course of drilling and grouting, and thus to optimize the key technical parameters of the post-processing technology. In this paper, on the basis of the analysis of consolidation process and treatment mechanism of the post-processing under the conditions of saturated soft soil, the research of optimal design of the post-processing technology on the control of consolidation degree and bearing capacity is completed, which is of reference for the design and construction of the post-processing technology.

Abstract: Recycled concrete is a kind of composite heterogeneous material. Through the uniaxial compression experiment on recycled concrete specimen, the corresponding stress-strain curve is depicted with the major variables of replacement rate of recycled aggregate and time of corrosion by seawater, and the analysis of compression resistance capacity of recycled concrete sample is carried out by comparing common samples with those after the process of vacuum pumping. According to the results of comparison, the process of vacuum pumping can raise the strength of concrete by 9% to 22% and the lowering speed of compression resistance capacity rises as replacement rate of recycled aggregate goes up after the same corrosion period. The compression resistance capacity of the concrete specimen with replacement rate of 60% descends 50% to 80% faster than the sample with 30% of rate. DPDM technique is used to analyze deformation field, displacement field and strain field of concrete specimen during the process of uniaxial compression. As shown in the images from the experiment, the cracks develop from the bottom and both edges towards the middle part along the direction of loading until some of them run through the cube with the failure of the overall specimen while the stress reaches the peak, the displacement amount decreases from bottom to top and from both edges to center and the greatest strain concentration scatters around the bottom of the specimen while the strain of 62% appears around the peak stress of 33-36MPa. This paper puts forward constructive references and guidance for the application of recycled concrete in marine engineering on the basis of the study of field effect through uniaxial compression experiment based on DPDM technique.