Tag Archive for Tag: Loads

Tag: Loads Design Loads

Loads are the external forces acting on a structure. Stresses are the internal forces that resist them. Depending on that manner in which the loads are applied, they tend to deform the structure and its components—tensile forces tend to stretch, compressive forces to squeeze together, torsional forces to twist, and shearing forces to slide parts of the structure past each other. Types of Loads

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Tag: Loads Design Loadings

Bridges must be designed to carry the specified dead loads, live loads and impact, as well as centrifugal, wind, other lateral loads, loads from continuous welded rail, longitudinal loads and earthquake loads. The forces and stresses from each of these specified loads should be a separate part of the design calculations. Also, because rail cars have changed in size and weight over the years

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Tag: Loads Nominal Loads

The nominal loads for design should be according to the applicable code or specification under which the structure is designed or as dictated by the conditions involved. In the absence of a code or specification, the nominal loads should be those stipulated in the American Society of Civil Engineers Standard, Minimum Design Loads for Buildings and Other Structures, ASCE 7. The following loads are

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Tag: Loads Member and Connection Design for Lateral Loads

Wind loads on steel structures are determined by first establishing the pressure distributions on structures after considering the appropriate design wind velocity, the exposure condition, and the local variation of wind pressure on the structure (Art. 9.2). Then, the wind loads on frames and structural elements are determined by distributing the wind pressure in accordance with the tributary areas and relative stiffness of the

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Tag: Loads Forces in Frames Subjected to Lateral Loads

The design loads for wind and seismic effects are applied to structures in accordance with the guidelines in Arts. 9.2 to 9.5. Next, the structure must be analyzed to determine forces and moments for design of the members and connections. Member and connection design proceeds quite normally for wind load design after these internal forces are determined, but seismic design is also subject to

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Tag: Loads Determination of Wind Loads

Wind loading as described in Art. 9.1 is the basis for design wind loads specified in ‘‘Minimum Design Loads for Buildings and Other Structures,’’ ASCE 7-88, American Society of Civil Engineers. Model building codes specify simplified methods based on these provisions for determining wind loads. These methods can be used for most structures. One such method is incorporated in the ‘‘Uniform Building Code’’ (UBC)

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Tag: Loads Hollow Structural Sections

Design criteria for round and rectangular hollow structural sections (HSS) used as structural members in buildings is given by AISC in ‘‘Specification for the Design of Steel Hollow Structural Sections.’’ The specification can be used for the design of the HSS materials listed in Table 1.7 and also for A53 Grade B pipe (35 ksi minimum yield stress and 60 ksi minimum tensile

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Tag: Loads Compression

Compressive forces can produce local or overall buckling failures in a steel member. Overall buckling is the out-of-plane bending exhibited by an axially loaded column or beam (Art. 6.17). Local buckling may manifest itself as a web failure beneath a concentrated load or over a reaction or as buckling of a flange or web along the length of a beam

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Tag: Loads ASD and LRFD Specifications

The American Institute of Steel Construction (AISC) has developed design specifications for structural steel with two different design approaches: ‘‘Specification for Structural Steel Buildings—Allowable Stress Design (ASD) and Plastic Design’’ and ‘‘Load and Resistance Factor Design (LRFD) Specification for Structural Steel Buildings.’’ Building codes either adopt by reference or incorporate both these approaches. It is the prerogative of the designer to select the approach to

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Tag: Loads Combined Loads

The types of loads described in Arts. 6.4 to 6.10 may act simultaneously. Maximum stresses or deformations, therefore, may result from some combination of the loads. Building codes specify various combinations that should be investigated, depending on whether allowable stress design (ASD) or load and resistance factor design (LRFD) is used. For ASD, the following are typical combinations that should be investigated:

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