ICE - Institution of Civil Engineers - Virtual Library

Papers.] LEA ON INFLUENCE-DIAGRAMS FOR GIRDERS. 277 (Paper No. 392 1 . ) " Influence-Diagrams for Continuous Girders." [Abridged.] By FREDERICK CHARLES LEA,DSc., Assoc. M. Inst. C.E. IN a Papercontributedtothe Proceedings in 1905, theAuthor showed how the " influence-diagrams " for the members of a latticegirder bridge could be drawn, and used to determine the stresses produced in the members due to any system of wheel-loads passing over the girders.1 The desirability of having some simpler method, than at the time known to the Author, of determining the effect of such travelling wheel-loads in producing shear and bending moment a t the sections of continuous girders occurred t o him some years ago while enga...

Proc. Instn Ciu. Engrs, Part 2, 1975, 59, Mar., 149-168 7782 Influence surfaces for orthotropic steel bridge decks An analytical method to produce influence surfaces for stiffened steel bridge decks is described. It uses dynamic relaxationto solve the finite difference formof the ortho- tropic small deflexion plate equations and employs a variable orthogonal mesh to ensure maximum economy of computer time and storage. The theoretical influence surfacesshowgoodagreementwithonesderivedexperimentally on quarter scale models of the two most common types of steel deck. Both the experimental and theoretical results show also that the use of torsionally strong stringers rather than torsionally weak stringers can reduce the maximum stringer bending stresses by to up 50% for decks of approximately the same weight...

Proceedings.] CHERRY ON EARTHQUAKES. 303 (Paper No. 4830.) "The Influence of Earthquakes on Structural Design." By HERBERT CECIL EDGAR CHERRY, MSc., M . Inst. C.E. HAVING engaged in engineering work in Burma, where earthbeen quakes occur periodically, causing loss of life, damage to property, and constant anxiety, the Author has investigated the records of scientificknowledge on the subject, with the object of ascertainingwhat principles of design ought to be adopted in order to minimize the risk of earthquake damage to structures in seismic regions...

TECHNICAL NOTE An influence coefficient method for pretensioned cable systems P. Krishna, ME, DIC PhD* S. R. Sparkes, MSc, PhD, FlCEt Introduction The method of influence coefficients been usedbefore to analyse suspension has bridges1 and in otherstructural problems. An approach, based on similar principles, is described in this Paper for the analysis of pretensioned cable systems. The method is illustrated by application to a,cable system, comprising two cables of reverse curvature, pretensioned together by means of a set of uniformly spaced vertical hangers with equal tension...

Proc. lnsrn Ciu. Engrs, Part 2, 1979, 67, June, 551-552 81 18 DISCUSSION The influence of control processes in structural engineering R. E. MELCHERS Mr G. S. T. Armer, Building Research Establishment The Paper brings a breath of fresh air to the subject of control processes in building construction. I imagine thatfor reasons of continuity withexisting literature, the Author has concentrated on actual structural failure and so-called structural safety. This latter term must be classed as one of the ill-conceived concepts referred to in 5 1...

BRIEFING European influences-Eurocode 2 PYOfeSSOY F. Levi, Chairman of the EC2 Editorial Group, 1984-1990 50 cc, z U 1 4 lzl Eurocode 2 (EC2) was issued at the beginningof 1992 by the ComitC Europeen de Normalization (CEN), acting under the mandate of the EEC, as a Provisional European Standard (ENV) on the designof concrete structures. Its origins, however, date back along way-after World War 11, the need for a sound comparison between the approaches used for the analysis and verification of concrete structures was felt by the specialists involved in building activities...

7137 The influence of shape on the stresses in cooling towers Membranestressesresultingfrom the action ofwind and self-weightloading on shells of the type employed in cooling tower construction, used to choose uniform are shellthicknesseswhichlimitallstresses to specificmagnitudes.Thestructurally most efficient meridional profiles are then assessed from the standpoint of minimum requiredmaterialvolume and foundation loading.Theresults are presented in a form suitable for design purposes. Because of its influence in controlling constructional cost the total surface area isalsoconsidered, and, whencombinedwithcertainconstructionallimitations, results in shells which for complete definition require the specification of only one other thermal-aerodynamic parameter...

Proc. Instn Ciu. Engrs, Part 2 , 1978, 65, Dec., 791-807 8118 The influence of control processes in structural engineering In the recent upsurge in interest in structural safety, significant emphasis has been placed on predicting failures and examining failure cases. Although such work is important for building up a better understanding of the problem, efforts should also be directed towards positive measures to prevent or reduce the incidence of failures. This Paper notespreviousworkinengineeringandnon-engineeringliterature to draw out the underlying themeof lack of foresight as a major contributor to structural failures...

A structure's influence on tunnellinginduced ground movements D. M. Potts, BSc(Eng), PhD(Cantab), MICE, CEng, and T. I. Addenbrooke, BEng, ACGI, MSc, DIC Proc. Instn Civ. Engrs Geotech. Engng, 1997, 125, Apr., 109125 Paper 11048 Written discussion closes 16 June 1997 Manuscript received 22 November 1995; revised manuscript accepted 8 May 1996 j The influence of tunnelling on buildings has become an important issue. The problem is an interactive one; not only do tunnelling settlements affect existing structures, but existing structures affect tunnel-induced soil movements...

7310 Wind analysis of complete building structures by influence coefficients K. I . MAJID, BSc, PhD, MICE, MIStructE' P. C. L. CROXTON, BSc, M l C E t InthisPaper a methodisproposed for the windanalysisofcompletebuilding structures consisting of skeletal frames, together with a grillage of shear walls and floor slabs.Thematrixdisplacementmethodisusedtoconstructinfluencecoefficient matrices for the bare frames and the grillage. These are then used in conjunction with a force method to satisfy the compatibility conditions at the junctions of the structure. The method is then extendedto include the effect of eccentric walls andframesandeccentricverticalloading...