Tag Archive for Tag: truss

Tag: truss Arrangement of Members of Plane Trusses-Internal Stability

Based on our discussion in Section 3.4, we can define a plane truss as internally stable if the number and geometric arrangement of its members is such that the truss does not change its shape and remains a rigid body when detached from the supports. The term internal is used here to refer to the number and arrangement of members

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Tag: truss Wood Trusses

Used in all forms of building construction for centuries, wood trusses have appeared in a wide variety of forms. They utilized many different wood and nonwood structural components. Development of preengineered, prefabricated, lightweight wood and wood-steel composite trusses, however, significantly altered previous practices, which employed relatively complex and labor-intensive types of trusses, each truss requiring a detailed engineering analysis. As a result, repetitive designs

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Tag: truss Long-Span Framing

Large industrial buildings, auditoriums, gymnasiums, theaters, hangars, and exposition buildings require much greater clear distance between supports than can be supplied by beam and column framing. When the clear distance is greater than can be spanned with rolled beams, several alternatives are available. These may be classified as girders, simple trusses, arches, rigid frames, cantilever-suspension spans, and various types of space frames, such as folded

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Tag: truss Roof Trusses

A truss is a coplanar system of structural members joined together at their ends to form a stable framework. If small changes in the lengths of the members due to loads are neglected, the relative positions of the joints cannot change. Characteristics of Trusses Three bars pinned together to form a triangle represents the simplest type of truss. Some of the more

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Tag: truss Stress and Strain

Structural capacity, or ultimate strength, is that property of a structural member that serves as a measure of is ability to support all potential loads without severe cracking or excessive deformations. To indicate when the limit on load-carrying usefulness has been reached, design specifications for the various structural materials establish allowable unit stresses or design strengths that may not be exceeded under  maximum loading.

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Tag: truss Suspension-Bridge Analysis

Structural analysis of a suspension bridge is that step in the design process whereby, for given structural geometry, materials, and sizes, the moments and shears in stiffening trusses, axial loads in cables and suspenders, and deflections of all elements are determined for given loads and temperature changes. The stress analysis usually is carried out in two broad categories: static and dynamic. Static Analysis—Elastic

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Tag: truss Classification and Characteristics of Suspension Bridges

Suspension bridges with cables made of high-strength, zinc-coated, steel wires are suitable for the longest of spans. Such bridges usually become economical for spans in excess of 1000 ft, depending on specific site constraints. Nevertheless, many suspension bridges with spans as short as 300 or 400 ft have been built, to take advantage of their esthetic features. The basic economic characteristic of suspension

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Tag: truss Guidelines for Preliminary Designs and Estimates

The usual procedure followed by most designers in preliminary designs of bridges involves the following steps: 1. Preliminary layout of structure 2. Preliminary design of floor system and calculation of weights and dead load 3. Preliminary layout of bracing systems and estimates of weights and loads 4. Preliminary estimate of weight of main load-bearing structure 5. Preliminary stress analysis 6.

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Tag: truss Continuous Trusses

Many river crossings do not require more than one truss span to meet navigational requirements. Nevertheless, continuous trusses have made possible economical bridge designs in many localities. Studies of alternative layouts are essential to ensure selection of the lowestcost arrangement. The principles outlined in preceding articles of this section are just as applicable to continuous trusses as to simple spans. Analysis of the stresses

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Tag: truss Truss Supports and Other Details

End bearings transmit the reactions from trusses to substructure elements, such as abutments or piers. Unless trusses are supported on tall slender piers that can deflect horizontally without exerting large forces on the trusses, it is customary to provide expansion bearings at one end of the span and fixed bearings at the other end. Anchoring a truss to the support, a fixed

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