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Showing papers on "Portal frame published in 1983"


Patent
14 Jun 1983
TL;DR: In this paper, a process for fabricating a building module is disclosed and claimed, where the building module includes a load bearing frame, and the frame is produced in subsections, namely two portal frame subsections, a floor frame subsection, a roof frame subsection and optionally cantilever section frame subsections.
Abstract: A process for fabricating a building module is disclosed and claimed. The building module includes a load bearing frame, preferably utilizing metal components welded together. The frame is produced in subsections, namely two portal frame subsections, a floor frame subsection, a roof frame subsection, and optionally cantilever section frame subsections. The various frame subsections are assembled with the use of jigs which monitor correctness of the appropriate components, after which the subsections are transferred to a final frame assembly site, where they are located on jigs which properly position same with respect to other subsections, after which the subsections are secured to each other to form a unified module frame. The frame is then lifted and casters or the like are removably secured to a lower portion of same, whereby the completed frame may be moved, preferably on a trackway, past a plurality of finishing stations where predetermined further assembly steps are performed at each such station. In a most preferred embodiment, a monolithic concrete slab floor is utilized in conjunction with the module frame with pouring formwork removably secured to the frame at the final assembly site for movement with the frame to a pouring station where the concrete is cast into the formwork, finished and cured. Thereafter the formwork is removed and the frame is moved past the remaining module finishing stations. A building module may thus be virtually completed in a factory environment, except for fabrication steps that are required to be conducted at the building site relative to association of one module to another to ensure coplanarity of adjacent surfaces and to properly locate the module on an appropriate foundation.

22 citations


01 Aug 1983
TL;DR: In this article, the critical softening parameter for a first-formed hinge in a continuous beam or portal frame was derived and the soft points at which a (sub CR) is a minimum may be found for each member.
Abstract: Softening behaviour is assumed to occur over a finite hinge length at any point in a continuous beam or portal frame. Formulae are derived for the critical softening parameter for a first- formed hinge corresponding to which the structure as a whole cannot sustain increased load. "Soft points" at which a (sub CR) is a minimum may be found for each member. Analytical values for a (sub CR) are verified in an example where softening occurs in the first formed hinge of a portal frame. (Author/TRRL)

12 citations


Journal ArticleDOI
TL;DR: In this paper, a method for modifying the stability analysis for flexibly-connected building frames is presented, and experiments are made on the effects of connection stiffness on frame buckling capacity.
Abstract: Most stability analyses of building frames are based on the assumption that the beams and columns are rigidly connected. However, many beam-to-column connections exhibit nonrigid, flexible behavior. This paper presents a method for modifying the stability analysis for flexibly-connected frames. The procedure is demonstrated for a simple portal frame, and observations are made on the effects of connection stiffness on frame buckling capacity.

9 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of simultaneous overall and local buckling in a simple portal frame with the same boundary condition described by the same beam model is investigated and the results show that imperfection sensitivity in the presence of local and overall buckling is higher in comparison with the previous case.
Abstract: In two previous works the effect of simultaneous overall buckling modes on post-buckling behaviour of a one-bay-two-storey frame with rigid beams, flexible columns and fixed edges has been analysed on the basis of the nonlinear theory of elastic stability developed by Koiter In the present article interaction effect of simultaneous overall and local buckling in a simple portal frame with the same boundary condition described by the same beam model is investigated Far from being conclusive, results so far obtained show that imperfection sensitivity in the presence of local and overall buckling is higher in comparison with the previous case

6 citations


Patent
05 Jan 1983
TL;DR: In this paper, a portal frame structure is provided comprising a horizontal truss (10) and vertical supports (11, 12) secured to the respective ends of the truss, with a joint arrangement intermediate its end, such that outside elements (15, 16) on one side of its neutral axis (X-X) are maintained in compression, and that outside truss elements (18, 19) on the other side of said neutral access are subjected to predetermined tension, such as as the load increases in one of said load directions the tension is reduced, and to tension exerted in
Abstract: A portal frame structure is provided comprising a horizontal truss (10) and vertical supports (11, 12) secured to the respective ends of the truss (10), the truss (10) being provided with a joint arrangement (13) intermediate its end, said joint arrangement (13) being such that outside elements (15, 16) of the truss (10) on one side of its neutral axis (X-X) are maintained in compression in both directions of load on the truss, and that outside truss elements (18, 19) on the other side of said neutral access are subjected to predetermined tension, such that as the load increases in one of said load directions the tension is reduced, and to tension exerted in the other of said load directions. The predetermined tension may be zero, such that the joint arrangement collapses immediately a compressive load is applied. Alternatively, it may have a value such that it reaches zero at any point up to the maximum designed load for a particular building application. The portal frames are for use with cladding secured to the inner side of the frames.