224,860 research outputs found
Star quilts, by Lois Rossetta Robison Bridges
No full textImage of a Star quilt created before 1950 by Lois Rossetta Robison Bridges. Also includes questionnaires describing the quilt completed by Max L. Day as part of the Utah Quilt Guild\u27s documentation days held from 1988-1994. Present owner, Max received it form Lila Day as a wedding gift in 195
Modelling Extreme Traffic Loading on Bridges Using Kernal Density Estimators
No full textInnovations on Bridges and Soil-Bridge Interaction (IBSBI 2011), Athens, Greece, October 13-15, 2011Kernel density estimators are a non-parametric method of
estimating the probability density function of sample data. In this paper, the
method is applied to find characteristic maximum daily truck weights on
highway bridges. The results are then compared with the conventional
approach.Deposited by bulk impor
A mathematical model for assessment of material requirements for cable supported bridges: implications for conceptual design
No full textRecent technological developments have led to improvements in the strengths of materials, such as the steel and wire ropes used in the construction of cable supported bridges. This, combined with technological advancements in construction, has encouraged the design of structures with increasing spans, leaving the question of material and environmental costs behind. This paper presents a refined
mathematical model for the assessment of relative material costs of the supporting structures for
cable-stayed and cable suspension bridges. The proposed model is more accurate than the ones published to date in that it includes the self weight of the cables and the pylons. Comparisons of material requirements for each type of bridge are carried out across a range of span/dip ratios. The basis of comparison is the assumption that each structure is made of the same material (steel) and
carries an identical design load, q, exerted by the deck. Calculations are confined to a centre span of a three-span bridge, with the size of the span ranging from 500 m to 3000 m. Results show that the optimum span/dip ratio, which minimises material usage, is 3 for a cable-stayed (harp type) bridge, and 5 for a suspension structure. The inclusion of the self weight of cable in the analysis imposes limits on either the span, or span/dip ratio. This effect is quantified and discussed with reference to
the longest cable-supported bridges in the world completed to date and planned in the future
Richard C. Bridges to his Sister M., 16 April 1863
No full textLetter from Richard C. Bridges to his sister M. describing his participation in the capture of Suffolk, VA; mentions his affliction with the mumps; asks for drawers and pants, as well as thinner shirts for summer.https://egrove.olemiss.edu/ciwar_corresp/1777/thumbnail.jp
Comparative structural response of two steel bridges constructed 100 years apart
No full textThis paper presents a comparative numerical analysis of the structural behaviour and seismic performance of two existing steel bridges, the Infiernillo II Bridge and the Pinhao Bridge, one located in Mexico and the other in Portugal. The two bridges have similar general geometrical characteristics, but were constructed 100 years apart. Three-dimensional structural models of both bridges are developed and analysed for various load cases and several seismic conditions. The results of the comparative analysis between the two bridges are presented in terms of natural frequencies and corresponding vibration modes, maximum stresses in the structural elements and maximum displacements. The study is aimed at determining the influence of a 1 century period in material properties, transverse sections and expected behaviour of two quite similar bridges. In addition, the influence of the bearing conditions in the global response of the Pinhao Bridge was evaluated
Maximum dynamic stress on bridges traversed by moving loads
No full textMost current research on dynamic effects due to traffic load on simply supported bridges focuses on the mid-span section of the bridge, since this location corresponds to the worst static bending moment. However, the maximum total moment allowing for dynamics, may differ considerably from the maximum moment at mid-span. This paper shows how the maximum can occur in a section relatively far from mid-span with a significant difference in magnitude.Other funderJournal websitewww.bridgesjournal.comEuropean 6th Framework Programme ARCHES (Assessment and Rehabilitation of Central European Highway Structures)Publisher requires the journal URL to appear on the record: www.bridgesjournal.com. Could use Description web link: Journal website as in http://hdl.handle.net/10197/2437? - AV 1/11/2010 au ke SB. 15/11/'1
The masonry bridges in Southern Italy: vestige to be preserved
No full textAfter the fall of the Roman Empire and the consequent breaking up of the territory into small free states, the need to build roads had an abrupt stoppage and many suburban bridges were abandoned too. The inquiry area is the Sannio, in which coexist many examples of: 1) ancient bridges still on use; 2) bridges of Samnite’ Age, adapted in the later centuries, nowadays in a marginal rule with respect to the roads net; 3) bridges cut off from the road system. The aim of this paper is to illustrate some of them in order to propose a cataloguing methodology of structural, technologic and material aspects of masonry bridges. The planned methodology last purpose is to preserve an adequate witness of this heritage and to lay the foundations to their safeguarding if, in the future, the sensibility towards these constructions would not depend only on their utilization
Richard C. Bridges to his Sister M., 27 March 1863
No full textLetter from Richard C. Bridges to his sister M. acknowledge receipt of her letters; prophesies battles at Murfreesborough and on the Rappahannock once the weather clears; dismisses rumors of demoralized Union army; expects war to go on for up to five more years.https://egrove.olemiss.edu/ciwar_corresp/1776/thumbnail.jp
Richard C. Bridges to Sister M., 5 November 1861
No full textLetter from Richard C. Bridges to his Sister M recounting the bloody summer campaign of 1861 and October 4th offensive against General Meade; mentions adequate food and clothing, but a lack of tents; describes army life for their acquaintances.https://egrove.olemiss.edu/ciwar_corresp/1768/thumbnail.jp
Stressing sequence of steel cable-stayed bridges built by cantilevering
No full textThe construction of cable-stayed bridges by cantilevering implies several changes of geometry, stress and strain patterns during the assemblage of segments. The main target to be satisfied in the construction process is the achievement of the required final geometry and of a convenient state of stress for self-weight and sustained loads. The sequence of stay stressing and the values of prestressing forces at each stage of segment assembling have the main role for reaching the desired result of design, due to the large redundancy of cable-stayed structures.Among the different procedures proposed in the literature for initial cable force determination, the Partial Elastic Scheme (PES) Method has been already applied to cable-stayed bridges of small-medium spans. In this study the same methodology is extended to cable-stayed bridges with larger spans and steel decks, by considering the effects of geometric nonlinearity attributable to the cable sag. In this paper PES method is modified to take into account the axial stiffness of stays and the related nonlinear behaviour of the bridge. Nonlinear analyses are performed with forward staged-construction finite element procedures and different strategies for establishing the initial value of stay stressing at each stage are proposed and compared. A case-study is investigated applying different approaches of stressing sequence. Results show the applicability of PES method to large cable-stayed bridges, when nonlinear staged construction analyses are performed and initial prestressing axial forces are found by linear partial elastic schemes
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