In contrast bridges are subject to repeated loads. This approach is normally acceptable for most building structures. The stress resultants may thus be transferred according to a statically admissible scheme. Where the loading is predominantly static, implicit allowance is normally made for plastic redistribution. the internal forces should be carefully identified and the magnitudes of load components determined so that equilibrium is satisfied. In addition, when considering the load paths of the internal forces through the components of the splice, due attention should be paid to possible changes in the magnitudes of the lever arm when the load transfers from the structural part into the splice components, i.e. Where eccentricities cannot be prevented, then relevant additional forces and moments should also be taken into account. Good practice should require that spliced parts be arranged so that any eccentricity between their respective centroidal axes is avoided. Secondly, consideration should be given to any second-order effects due to geometric non-linearities and imperfections. The internal forces to be transmitted by a specified splice are firstly, the axial force, bending moment and/or shear force which occur in the joint based on elastic or plastic structural analysis of the structure, assuming continuity through the joint. The splices shown in Figure 1 illustrate most of the possible arrangements. type of loads to be transferred, the types of structural sections - open or closed sections, ease of access, nature of the loading - static or dynamic, with or without load reversal - and stiffness. Many factors influence the choice of type of splice, e.g. Such splices are used when assembling members of the same or nearly the same serial size (Figure 1d). In a butt welded splice, full continuity of the section is maintained across the joint cross-section. Such elementary splice arrangements are not considered further in this lecture. The plate parts are simply overlapped and connected to each other by bolts or fillet welds (Figure 1c), or even by screws for very thin plates or sheeting. Such connections are used especially when splicing single plates or sheeting components. In overlapped splices there is no need for cover plates. Where end plates are used in a splice they are usually positioned perpendicular to the member axes and fixed by fillet welds (Figure 1b). Cover plates may be single, with bolts in single shear, or double with bolts in double shear (Figure 1a). Most splices transfer loads from one structural member to the adjacent part of a similar structural member through either cover plates or end plates. For example, traditional cover plates may used for full load transfer or just for continuity welds or bolts may be chosen as fasteners. As with any other kind of connection, splices should be designed to the general principles, and design concepts presented earlier, see Lectures 11.1. The reasons why splices are required as well as the advantages and disadvantages of the respective types of fasteners have been discussed elsewhere see Lectures 11.1. This transfer is normally made through different kinds of transitional plate elements which are appropriately fastened onto the member parts. It is aimed at transferring the internal forces from one structural part to the adjacent one without being a weak point of the structure in relation to strength, stiffness and, ductility. INTRODUCTION 1.1 Types of SplicesĪ spliced connection is a joint made within the length of a stanchion, a beam or any other structural member. Initially load paths must be determined the resistance of all components on these load paths must be checked. Splices are designed to transfer axial force, shear force and bending including parasitic moment and second-order effects. Lecture 15B.11: Splices and other Connections in Bridges SUMMARY Lectures 11.4: Analysis of connections RELATED LECTURES Lecture 11.1.2: Introduction to connection design The main aspects of fabrication and erection are briefly reviewed. To present the basic guidelines and concepts for the design of splices in buildings as well as basic arrangements for splices in tension and compression members and in members subject to bending. CONNECTION DESIGN: STATIC LOADING Lecture 11.8: Splices in Buildings OBJECTIVE/SCOPE
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