Truss connections

A frame is a structure with at least one member that supports more than two forces. Members of a frame may support lateral as well as axial forces. Connections in frame need not be located at the ends of the members. Frames, like trusses, are designed to support loads, and are usually motionless. A machine also has multiforce members. It is designed to modify and transmit forces and, though it may sometimes be stationary, it always includes parts that move during some phase of operation. 

For purposes of this specification, stresses in the individual members of a latticed or trussed structure resulting from elastic deformation and rigidity of joints are defined as secondary stresses. These secondary stresses may be taken to be the difference between stresses from an analysis assuming fully rigid joints, with loads applied only at the joints, and stresses from a similar analysis with pinned joints. Stresses arising from eccentric joint connections, or from transverse loading of members between joints, or from applied moments, must be considered primary stresses. 

A wood-based composite can be defined as a composite material mainly composed of wood elements. These wood elements are usually bonded together by a thermosetting adhesive (wood truss products could also be regarded as wood-based composites, but connected by metal connectors). The commonly used adhesives include urea-based adhesive (such as urea formaldehyde resin), phenolic-based adhesive (including phenol resorcinol adhesives), isocyanate-based adhesive, and adhesives from renewable resources (like soybean, lignin etc). The wood elements in wood composites can be in many different forms such as ... 

The primary structural role of the face/core interface in sandwich construction is to transfer transverse shear stresses between faces and core. This condition stabilizes the faces against rupture or buckling away ftom the core. It also carries loads normally applied to the panel surface. They resist transverse shear and normal compressive and tensile stress resultants. For the most part, the faces and core that contain all plastics can be connected during a wet lay-up molding or, thereafter, by adhesive bonding. In some special cases, such as in a truss-core pipe. 

These attributes and their values are shown in a conceptual design representation space below. A combination of values describing a truss is shown in the table as bolded words. Obviously, a steel truss is a steel structure with straight members that are connected by hinges that is, a steel truss is described by a specific combination Al Material = Steel, A2 Member Shape = Straight, and A3 Connection Type = Hinged (Table 4.2). 

Stressed skin panels of floors, walls, roofs, box beams and trusses are examples of primary structural applications where the connection is expected to carry static and dynamic design loads without failure. 

Failure of the lower joint-column connection due to creep by the cold shut or due to shear at the upper end of column resulting from the shear component of the force of equivalent truss transferred by the infill of stmctnral mesh... 

The reinforcement of wood trusses, designed in collaboration with Eng. Domenico Morrone, was realized by the replacement of deteriorated with new wooden elements connected to the structure by means of glass liber bars (Fig. 10.18). 

Packer, J.A., Hraiderson, J.E., 1997. Hollow Structural Section Connections and Trusses A Design Guide, First edition 1992, second edition 1997. Canadian Institute of Steel Construction, Canada. 

Architecture. Manned space stations are designed to be used as semipermanent habitats and laboratories. Therefore, they are roomier and have more advanced life-support systems and are technologically more complex than other space vehicles. The ISS exemplifies this design consideration It is 240 feet long and 356 feet wide, with more than 12,000 square feet of room in which to live and work. It is also modular, with solar arrays, pressurized living and research modules, connector nodes, storage modules, and other pieces all connected around a central truss system. Each piece of the ISS is launched into space (either aboard a shuttle craft or rocket) and locked into place. The last component of the ISS was scheduled to be added in 2011. 

In this sub-section consideration is given to some of the features of tests that have been carried out on axially loaded bolted and bonded joints. These joints arise predominantly in truss-type structures or in bracing systems used to resist sway of simply connected beam and column frame structures. 

Repair of decayed timber connections (Fig. 22.6(c) e.g., in roof trusses). 

Structural analysis showed the need to reinforce a number of joints in the top chord of one of the truss arches (Fig. 22.8) to enhance their resistance to wood splitting perpendicularly to the hbres. The perpendicular to wood grain reinforcement of the timber member, in the connection, was performed by internal bonding of threaded rods. These rods were inserted perpendicularly to the existing metallic fasteners close to the beam end (Fig. 22.9). Three rods were used per joint, located just after the beam joint fasteners (Fig. 22.10). The threaded rods, having a diameter of 16 mm, were bonded into... 

Rehabilitated truss arch exhibiting the three reinforced connections (courtesy of Helena Cruz and Pedro Palma). 

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