Advanced Materials Research Vols. 163-167

Abstract: The reinforced concrete (RC) frame-tube structure considered in the study has two towers with lapping transfer columns. The lapping transfer columns, considering aesthetic requirement in elevation, lead to a complex vertical force transfer system. The large irregularity in elevation, according to Chinese code, necessitates a detailed study. A 1/15-scaled model of the high-rise building was tested on a shaking table to evaluate its seismic performance. The model was subjected to earthquake inputs representing frequent, basic, rare, and extremly rare earthquakes. The results of shaking table test in terms of the global and local responses as well as the dynamic properties are presented. The tests demonstrate that the designed structural system satisfies the pre-defined performance objectives and the lapping transfer columns have good seismic peformance. To better control seismic damages of the building, some suggestions for improving the design of this structure are also put forward at last.

Abstract: Based on the literatures and the existent researches, the study on segment joint of prestressed concrete lining has been carried out. The analytical solution for calculating the rotational angle of the joint are deduced with the calculation assumption. So the rotating stiffness of joint is obtained. Compared with the experimental results, the numerical calculation suggests that the theoretical equations are reliable. Study shows the slip length of prestressing steel strand near the joint is one key to calculate the rotational angle and rotating stiffness of joint. The matched curve of the slip length with joint bending moment is given in the paper, which can be described by logarithmic function. When the rotational angle of the joint is calculated, the slip length could be regarded as a constant to simplify the calculation.

Abstract: Bedding cushion cracking in concrete dam is widespread, and has not been completely prevented [1,2]. There are many cracking causes of bedding cushion, including construction difficulty and structure requirements for concrete dam. Based on the method of FEM simulative calculation of temperature and stress fields of mass concrete using water cooling pipes, this paper makes relatively in-depth study on crack mechanism for concrete bedding cushion on rock. It is revealed that all three factors of uneven thickness of bedding cushion, thickness of new dam concrete placed on cushion after off period and foundation gallery upon bedding cushion have great influence on the tensile stress of bedding cushion and should be paid special attention during construction. The calculation results show that the tensile stress of thinner concrete cushion layer is much greater than the thicker one, and the thinner upon new concrete will also make greater tensile stress in cushion. As a result, both the thinner cushion layer and the cushion with thinner new concrete on it would have a bigger chance to crack than others. The mechanism is used to explain reasonably a dam crack in construction. Then some cracking prevention measures, which should have reference value for the construction of bedding cushion, are put forward in this paper.

Abstract: The impact of temperature stress cannot be ignored in actual project. Single-frame shear wall structure of two-dimensional plane has been simplified in this paper. Fixed point of displacement under the influence of the temperature is determined in structure. Model for Calculating is given. Temperature stress of frame - shear wall cast plate is found by matrix method.

Abstract: Using flexibility-based finite element method based on fiber model, several experiments of reinforced concrete specially shaped columns under cyclic loading which cross section is ‘L’, ‘T’ and ‘+’ shape with different longitudinal reinforcement and hoop reinforcement have been simulated, and the seismic behavior of columns such as strength, ductility and energy dissipation are analyzed. Results from the analytical study indicate that: 1) ductility of the column increases as quantity of hoop reinforcement increases. 2) strength capacity of the column increase linearly as ratio of longitudinal reinforcement increase, but is not seriously affected by hoop reinforcement; 3) energy dissipation capacity of the column is not significantly affected by hoop and longitudinal reinforcement, particularly in slightly nonlinear range.

Abstract: The deformation characteristic load-deformation curve, failure Patten and the load bearing capacity of concrete block shaft lining under uniform and non-uniform load condition are presented. They were got from the mechanical property test of layered concrete block masses. And the large Structure test of concrete block lining series of test data are provided for the design and calculation of concrete block lining, and the deformation control under sinking of freezing shaft in which this kind of lining is utilized.

Abstract: In this paper, thermal stresses due to variation of air temperature , surrounding soil elastic constraint and other effects on the basement wall and floor. Though finite element method (FEM )elastic analysis, thermal stresses distribution on the wall and floor to be drawn and qualitative summary of the variation thermal stresses with the change of walls` length and floor`s thickness.

Abstract: Inner reinforced concrete-block composite shaft lining was widely used in vertical shaft sinking by vertical shaft sinking machine (VSM) and freezing shaft. In this paper, the deformation characteristic, failure Patten and the load Bering capacity of inner reinforced concrete-block composite shaft lining are presented ,based on the model test .and the test data are provide for the design and calculation of this kinds of composite shaft lining.

Abstract: The number of high-rise reinforced concrete (RC) buildings is steadily increasing since 1980’s. The use of high strength concrete is indispensible for high-rise RC construction to ensure sufficient strength of the structure. The effect of high strength concrete can be significantly improved by the use of high strength and large size reinforcing bars. The yield strength of transverse reinforcement is limited in the current design codes to prevent possible sudden concrete failure due to over reinforcement. This paper presents the effects of the yield strength of transverse reinforcement and compressive strength of concrete on the structural behavior of reinforced concrete cylinders. Two parameters were considered in this investigation: compressive strength of concrete and the yield strength of transverse reinforcement (472MPa, 880MPa, and 1,430 MPa). Analytical and experimental results indicated that the structural behavior of RC cylinders confined with high strength transverse reinforcement is strongly influenced by compressive strength of concrete.

Abstract: A laboratory test of anchor pull-out model under plane-strain condition on the shear stress transfer for the interfaces of anchorage type structures was carried out in this paper. The results of test were verified by corresponding numerical simulation model. It was proved that the pull-out experimental model under plane-strain condition was an effective model used to research the working mechanism of anchorage structure.