Search

The temperature effect often significantly affects the performance of large-span spatial structure and even becomes one of the controlling loads. To obtain the non-uniform temperature field distribution of the thin-walled steel members under solar radiation and the influence rules of various factors, in this paper, experimental studies are carried out with three groups of specimens including rectangular steel tube, I-shaped steel and circular steel tube. Based on the test data, the non-uniform temperature field distributions considering the influence of solar radiation intensity, member size and surface coating are analyzed in detail. Then, numerical methods for the temperature field of steel members are studied considering multiple environmental factors. The validity of the numerical method is evaluated with test results. Finally, based on the parametrical studies of the major influence factors, a simplified calculation approach is presented for practical engineering applications. The experimental study demonstrates that the non-uniform temperature distribution of steel members truly exists and cannot be overlooked. The numerical method for the temperature field in this paper is effective, and the simplified calculation approach can meet the required engineering precision. The research methods and conclusions of this work can provide valuable references for thermal design, monitoring and control of steel structures. [ABSTRACT FROM AUTHOR]

Most existing studies on single-layer spatial structures with semi-rigid joints were focused on spherical domes. The present paper analyzed the squared plan-form single-layer structures, examining the influence of joint-rigidity on the mechanical performances of the structures. An experiment has been conducted on a 5×6 m single-layer cylindrical reticulated shell with semi-rigid bolt-ball joints. The mechanical performance of the latticed shell is investigated in detail. Finite element analysis (FEA) model of the latticed shell is established taking material and geometric nonlinearities into account. The results show that the behavior determined using the FEA models correlates well with the experimentally observed behavior for the single-layer structures with semi-rigid joints. [ABSTRACT FROM AUTHOR]

Joints transfer forces propped by members to other sections of space frame. It support and connect braces with other members which provide restraints to members. In general, joints behavior is ideally rigid or ideally pinned (flexible) in typical design and study of space frames; ideally rigid Joints cannot undergo rotation and ideally pinned joints cannot transfer moment. In reality, rigid joints have relative flexibility which makes them rotate and ideally pinned have means to transfer moments. Thus, real space frame both idealized models are not real and all joints present a semi-rigid behavior [1,2]. Thus, real joint in space frame is "semi-rigid". Several tests have plainly shown that joints behave nonlinear because of gradual yielding of joint parts such as; plates, angles, bolts. Space frame buildings use bolted joints. However, joint behavior is complex to analyze because of discontinuities in joints areas. Features which influence joints behavior includes; bolts positions and spacing, bolts pretension and material properties. Other features such as; joints parts and contact areas evolution, compression center positions and stiffeners presence can change joints behavior. Tests can predict joints behavior, as well as elaborated modeling and analytical approaches. Space frames joints work under axial force, shear force, and bending moment. However, for most joints, axial and shear deformations are usually small liken to bending deformation [2]. This work considers only joints rotational deformation because of bending action. The present paper includes design of Aluminum bolted joints and explores it behavior experimentally. Also it analyzes and models the moment-rotation behavior of these joints by using Finite Element Model and mathematical formulas. Which will finally help to integrate the moment-rotation curves efficiently into a Space frame analysis computer program. • Aluminium joints mechanical performancesunder static loading. • Aluminium semi-rigid joints behavior. • Aluminium semi-rigid joints Numerical study. • Aluminiumsemi-rigid jointsmathematical predictionmodel. [ABSTRACT FROM AUTHOR]