Advanced Materials Research Vols. 838-841

Abstract: This paper reports on a part of an ongoing experimental program at the University of Adelaide on the behavior of fiber reinforced polymer (FRP)-concrete-steel double-skin tubular columns (DSTCs). Influence of concrete-filling inner steel tube on the compressive behavior of FRP-concrete-steel DSTCs was investigated experimentally through the test of 8 normal-and high-strength concrete DSTCs. The results of the experimental study indicate that concrete-filling inner steel tubes of DSTCs results in a slightly increase in the compressive strength and decrease in the ultimate strain of concrete in DSTCs, compared to companion DSTCs with hollow inner steel tubes. The results also indicate that concrete in both types of DSTCs is confined effectively by FRP and steel tubes.

Abstract: Beam-column connection with cantilever beam bolted-splicing is also known as the joint of column-tree moment-resisting frame. The study is still relatively small for the semi-rigid behavior and rotational stiffness of the joint. This paper deal with four specimens of the joints with cantilever beam splicing and four specimens of the welded joints by using three dimensional finite element model analysis. The strain, stress, yield and ultimate loads, yield and ultimate deformations had been compared between the joint with cantilever beam splicing and the welded joint. The analysis results show that, when the splicing area of the joint with cantilever beam splicing was designed more strongly, the stress distribution, the load-displacement curves in elastic working stage, and the initial rotational stiffness are good agreement between the joint with cantilever beam splicing and the welded joint. The hysteresis curves of the joint with cantilever beam splicing were inverse S-shaped, indicating that there was greater slipping deformation because of bolt splicing. The welded joint had no slipping phenomenon.

Abstract: This paper presents the results of numerical analysis of hollow floor supported by the column under vertical load and horizontal load. The validity of three different analogue methods were examined and compared. The macroscopic elastic constitutive method (MEC) gave satisfactory predictions but involves an elaborate procedure for determining the equivalent elastic material parameters. The equivalent thickness approach (ETA) gave moderately higher values for the section moment than the exact values. An alternative simplified approximate method based on the effective elastic modulus (EEM) is recommended by the specification. Numerical calculation for section moments by the proposed method were on the safe side and close to exact results. The proposed method could also be appropriate for the column supported structure and the horizontal load.

Abstract: The structure of Wall-slab is composed of slab and shear wall, and only in the outer wall part are the shear wall connected by a coupling beam. The floor and shear wall can bear vertical force and horizontal lateral force together. While under the situation of irregular bearing form shear wall and irregular partition loads, tablet computing becomes an urgent problem. Aiming at this problem, the model which is one layer of floor of Wall system has been used for analysis through the Safe software. In the condition of different thickness of slabs, exploratory results can get about the slab deformations, stresses and reinforcement ratios. The paragraph provides the basis to determine the optimal thickness of plate.

Abstract: Sliding mode control is a good way to design controller with self-adaptive and robustness, It can be used to discuss the vibration problems of mechanism and structure with time-delay. By using constant-speed approach, the controller is designed law and the stability criterion presented without delay information, which make the stability analysis of the vibration structure with time-delay straightforward.

Abstract: High strength steel composite K-type eccentrically braced frame is a new structural system, in which the link is made from low yield point steel and the others are made from high strength steel. In order to study the seismic behavior of such a structure, four one-bay one-story 1/2 scaled plane specimens were tested under the monotonic and cyclic load respectively. The failure modes and the main indexes of seismic behavior of specimens with various links length were analyzed. The results show that this new structural form is good at energy dissipation and ductility, and the way of energy absorbing by shear yield is better than by flexure yield. Under cyclic load, the main failure were concentrated at links, while the other parts of the eccentrically braced frame kept in elastic status. This kind of structure is an excellent dual resistance system and easy to rehabilitate after earthquake.

Abstract: Early-age autogenous shrinkage is key problem of high performance concrete. It can cause a lot of early-age cracks in concrete structure and further endanger the permeability and durability. Adding expansion agent can control the early-age autogenous shrinkage strain and reduce the risk of early-age cracks. In this paper, the early-age autogenous shrinkage stress of concrete cube is calculated. The results show that, early-age autogenous shrinkage stress is larger than early-age tensile strength of concrete. So some cracks occur on the surface of concrete structure. By adding expansion agent, the early-age autogenous shrinkage strain and stress both decreases.

Abstract: This paper introduces a new double-wall fabricated steel insulation silo with multiple bolted joints. The software ANSYS is utilized to model a 1000-ton double-wall fabricated steel insulation silo with multiple bolted joints and calculate its stress and displacement. The silo is optimized by adjusting the wall thickness of the silo. The model which uses the original thickness is defined as Model 1. The optimized model is defined as Model 2. The stress and deformation of these two models were comparatively analyzed. The results show that the maximum stress and the maximum displacement of Model 2 are both smaller than the specified values. Furthermore,it saves about 40.7% with the steel quantity compared with Model 1.

Abstract: This paper describes the structure composition and characteristic of assembled self-supported warehouse. And its mechanical principle is introduced and compared with both the assembled pallet rack and the building structure. The assembled self-supported warehouse combines the two structure systems effect. The longitudinal horizontal load is transferred to foundation by means of roof truss and multi-pan portal rigid frame and the lateral horizontal load is transferred by means of spine bracing system and semi-rigid frame. Load on roof and goods load are transferred separately from roof truss and beams to columns, then these loads are transferred to foundation.

Abstract: A novel method based on the mutative scale chaos optimization algorithm is proposed to solve the robust reliability index of non-probabilistic reliability model. Compared with the basic chaos optimization method, this novel method can minimize searching area of optimization variable and change the adjustable parameters of next search stage for improving the optimization performance. The proposed optimization algorithm is more efficient and has smaller computational complexity in solving robust reliability index. The feasibility and efficiency of the proposed method are demonstrated by two examples.