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Arch bridges will produce horizontal internal force at arch springing under vertical load. The horizontal internal forces and displacement of abutments have significant influences on structural behavior of arch bridge, which was located at soft soil foundation. One of the effective methods to solve the problem is applied the pre-pushing technique behind abutment by two horizontal anti-slide slab. However, there is soil creep deformation at the arch springing under the long-term vertical load. Therefore, an unequal interval multivariable grey model was established to predict the soil creep deformation. This grey model was extended by a single point and equal interval model. The modeling steps are also proposed in this paper. And then the calculated results by the proposed model will compared with the measured results and the results of Burgers model. The compared results showed that it can precisely and effectively predict the amplitude of the creep deformations.

The mechanics analysis of integral building structure needs the accurate ABAQUS finite element analysis, but due to the ABAQUS function limits the building structure modeling is a great workload and how to model an integral structure more quickly and efficiently become a difficult problem. In order to reduce the workloads in the ABAQUS analysis, the new ABAQUS standard layer assembly modeling approach was proposed. Firstly, according to the data structure of the ABAQUS software’s INP file, the program computational algorithm was proposed. And by a Python self-written program, the example engineering structure model was completed using this standard layer assembly approach. The usage of this new ABAQUS modeling approach makes the modeling more easy and efficient. After that, by comparing the ABAQUS standard layer assembly model calculation results with the results calculated by another finite element software, it is clearly illustrated that the ABAQUS standard layer assembly modeling is more accurate and can be applied in the structure analysis.

Grout-filled mechanical splice system is one of the most important technologies for precast construction. However, due to the high cost of grouted sleeve in Chinese construction market, the implementation of this technology is hindered. In this study, a new type of grouted sleeve was developed with standard seamless steel pipe by cold rolling depression. Utilizing this sleeve, eight coupler specimens were prepared and tested under incremental tensile load and cyclic load. The results indicate that all the specimens provided satisfactory behaviour of which the ultimate tensile strength exceeded the required loading capacity specified in ACI318 and JGJ107. The inner cavity configuration of the grouted sleeve has great influence on the confining mechanism of the splice and on the strain distribution in the sleeve. Because the compressive strength of grout is greatly higher than its tensile strength, the slope of the load-strain response curve of the sleeve under tensile load is lower than it under compressive load.

On the basis of the domestic and overseas scholars’ research, it is innovative to put forward a new precast frame beam-to-column connection. One full-scale beam-to-column connection in a precast concrete（PC）frame and a beam-to-column connection in a cast-in-place concrete structures were tested under uni-directional cyclic loading that simulated earthquake-type motions. The new-type beam-to-column joint in a precast concrete frame consisted of cast-in-place columns and precast beams. Test results showed that（a）The property and action of precast connections are similar to the cast-in-place connection, it showed that both precast connections and cast-in-place connection have similar seismic performance; (b) The cracking load of precast connection are similar to the cast-in-place connection; (c) All the columns of all specimens did not destroy, it illustrate that it conform to the strong column weak beam. (d) In this experiment test, because the control factor use the bending capacity of beam, it also play the same plastic hinge mechanism as the traditional component. All the longitudinal reinforcement destruction ahead of stirrup in beams, which should be confirmed the guiding ideology of strong shear weak bending. On the basis of the test results, design considerations for the beam-to column connection were recommended.

This paper describes an ongoing research program on the seismic resistance performance of the double-wall precast concrete (DWPC) shear wall. Low-cyclic reversed loading test of three new full scale specimens are carried out based on the previous studies. The test results indicate that DWPC shear walls have higher initial stiffness, cracking load, yielding load and ultimate load. The displacement ductility ratios of DWPC shear walls are no less than that of cast-in-situ shear wall. The hysteretic curves of all specimens are plump, and the trend of skeleton curves is basically the same. The seismic energy dissipation capacities of DWPC specimens are close to those of cast-in-situ specimen. All the specimens have shown favorable seismic resistance performance.

To study the seismic behavior of Double-Wall Precast Concrete (DWPC) shear wall, three full scale specimens are tested and compared under low-cyclic reversed loading, including two DWPC shear walls and one normal Cast-In-Situ (CIS) shear wall. By observing their experimental phenomena and failure modes, contrasting their displacement ductility coefficients, hysteretic curves, skeleton curves and energy dissipation capacity, the seismic behavior were synthetically evaluated on aspects of strength, stiffness, ductility and energy dissipation. Compared with CIS specimen, DWPC specimens have higher initial stiffness, increased cracking loads by 43% to 47%, and the ultimate loads increased by 22% to 23%. The displacement ductility ratios also meet the ductility requirements with value of 5. The hysteretic curves of three specimens are plump, and the trend of skeleton curves is basically the same. The DWPC specimens demonstrated a good energy dissipation capacity. All the specimens had shown favorable seismic performance.

The precast roof truss of prestressed concrete square pile is a new self-balancing system composed of prestressed concrete square pile, strut and steel tension rod. Based on finite element analysis methods, the bending moment and deformation under most unfavorable design load was checked upon crack resistant bending moment to verify its engineering feasibility, the optimal prestressed value was analyzed to get the camber of the top chord beam, and the optimal tension method for bottom chord tension rod was determined. Compared with finite element analysis results, the full scale model test was carried out to further verify its engineering feasibility and some optimization recommendation was proposed. It suggests that the tension order of middle section before diagonal rod, initial prestressed value of 10t, and prestressed control method of monitoring camber at midspan is the most reasonable and optimal solution.

To correctly acquire steel strain and deformation of SRC during construction process, one SRC transfer storey used in ultra high connected structure is chose. By nonlinear finite element method and field measurement, research on steel beam strain and deformation of the SRC connected structure in the whole construction process is performed. Based on practical construction method, the numerical analysis model for the construction process is established. Combined with time-variation mechanics and nonlinear finite element method, construction mechanics of the SRC transfer storey is analyzed, considering temporary support and construction load in each construction stage. Meanwhile, the field measurement of SRC transfer storey is carried out, and then the comparison between calculate result and measured value. The results show that, calculate result tallies closely with measured value, the steel beam is in a low stress state in the whole construction process, and the deformation of SRC structure varies linearly. The conclusion is that, mechanical behavior of the SRC transfer storey in the whole construction process can be grasped by nonlinear finite element method, and also the reliability of such structures in construction period and service life.

In order to ensure the prestress establishment of large-span suspendome, research on the measure-control methods for large-span suspendome during prestress construction process is performed, by summarizing the existing measure and test methods. According to engineering practice at present, the paper classifies the measure-control content of large-span suspendome during prestress construction period into two parts: internal force of cable-strut and deformation of steel structure. Taking practical project of a gymnasium as an example, the axial forces of hoop cables, radial steel tie rods and struts are measured, and also the verticality of struts. The test results are analyzed, and compared with the calculated value. The results show that, the internal forces of cable-strut and verticality of struts can both meet the design requirement, by mechanical analyzing and precise monitoring of the whole prestress construction process. The conclusion is that, before the prestress construction of large-span suspendome, construction mechanics analysis must be carried out in details to determine the control content and its target value, right measure-control methods are chosen, and then the effective establishment of prestress can be achieved.

In this paper, the proposed idea of producing fully-enclosed composite cable with CFRP coupling of high-tensile steel wires and the forming technology of the fully-enclosed composite cable body were introduced. The coordination mechanism of the fully-enclosed composite cable, the requirement of equal elastic modulus between high strength steel wire bundle and CFRP were investigated theoretically. We have come to the follwing conclusions: (1) Carbon fiber has the same strain with the high-tensile steel wire under the tension of whole anchorage. (2) The distribution of the force of the composite cable is in accordance with the axial stiffness between the carbon fiber with high-tensile steel wire. (3) To achieve a good synergy between the carbon fiber with high-tensile steel wire, similar or equivalent elastic modulus is required. (4) The stress ratio between carbon fiber and high-tensile steel wire in the fully-enclosed composite cable in engineering application should be controlled around 0.5.