BRIDGET RILEY in Conversation with ROBERT KUDIELKA now that it is the "binary" look of my black-and-white work, which appealed to those who were familiar with computer logic. Nevertheless the... I did in MOVEMENT IN SQUARES. RK: This may be whv computer analysts are inclined Bridget Riley to

BRIDGET RILEY, DESCENDING, 1965/66, emulsion on boaid, 36 x 36" / ABSTEIGEND, Emulsion auf Ma Ik a > ion, 91,4 x 91,4 cm (PHOTO PRUDENCE CUMING ASSOCIATES LID)

? Bridget Riley BR: Well, many factors suddenly came together. There was the wall drawing for the

Bridget Riley (Ligeti)?4' The piece I played you, the so-called Warsaiv Etude, is based on sixteen... Collected Wntings 1965-1999, ed b\ R Kudielka (London Thames and Hudson, 1999), pp 66-68 3) Bridget Riley... BRIDGE1 RILEY, BLAZE I, 1962, emulsion on boaid, 43 x 43" / HELLES FLIMMERN I / Emulsion auf

Bt idgel Riley Bridget Riley 28 29

keineswegs zeitgebunden? Bridget Rilev: Vielleicht hat es damit zu tun, dass ich mein Urteil stets von... Arbeit an einer Monographie über Bridget Riley abgeschlossen sein. heit eher kritisch bewundernd ist

BRIDGET RILEY im Gespräch mit ROBERT KUDIELKA führung in Database-Design und seine Anwendungsmöglichkeiten erschienen, die das Bild MOVEMENT IN SQUARES (Bewegung in Quadraten) von 1961 auf dem..., mit hochentwickelten Zeichenprogrammen, nicht in der Lage sind, aus eigenem Vermögen ähn- Bridget

Bridget Riley 4 & BRIDGET RILEY, BLACK TO WHITE DISCS, 1961/62, emulsion on canvas, 70 x 70" / SCHWARZE BIS WEISSE SCHEIBEN, Emulsion auf Leinwand, 177,8 x 177,8 cm. (PHOTO: PRUDENCE CUMING ASSOCIATES LTD.)

Bridget Riley BR: Ja, die vielleicht erstaunlichste Entdeckung bestand darin, dass die Kurve mir nicht erlaubte, sie lediglich als eine weitere Form zu den bereits verwendeten hinzuzufügen. Sie wurde vielmehr bestimmend und verstärkte die Empfindung der Schwerkraft durch ihre Schwingung. Das

Bridget Riley BRIDGET RILEY, MOVEMENT IN SQUARES, 1961, tempera on board, 48 x 48" / BEWEGUNG IN QUADRATEN, Tempera auf Malkarton, 121,9 x 121,9 cm. (PHOTO: PRUDENCE CUMING ASSOCIATES LTD.) ?5

BRIDGET RILEY, PARADE 3, 2000, oil on linen, 89% x 201"/ Öl auf Leinen, 221,3 x 525,8 cm. (PHOTO: PRUDENCE CUMING ASSOCIATES LTD.)

gestellt hatte und über den Titel nachdachte, spielte ich tatsäch- BRIDGET RILEY, CANTUS FIRM US, 1972, acrylic on canvas, 95 x 84,5" / Aeryl auf Leintoand, 241,5 x 214,6 cm. Bridget Riley lieh... Schjeldahl, «British Flash: Having Fun with Bridget Riley and Damien Hirst», The New Yorker, 6. November

BRIDGET RILEY, NINETEEN GREYS, A, B, C, D, 1968, silkscreen on board, 30 x 30" each / NEUNZEHN GRAUTÖNE, A, B, C, D, Siebdruck auf Museumskarton, je 76,2 x 76,2 cm. 41

Edition for Parkett BRIDGET RILEY GOING ACROSS, 2001 Silkscreen print on Somerset satin; paper size 24 1/4 x 36" image 16 1/2 x 28 7/8". Printed by Sally Gimson for Artizan Editions, Hove, England. Edition of 90, signed and numbered. DURCHGEHEND, 2001 Siebdruck auf Somerset-Satin; Blatt 61,6 x 91,4

573 Seismic Performance of Long-Span Suspension Bridges in the USA Comportement sismique des ponts... International; Vartan SAHAKIAN, Bridge Department Manager, Commonwealth Engineers & Consultants, Inc.; Vinaya... Engineer, Research, MTA Bridges & Tunnels; Ronald J. WATSON, President, R. J. Watson, Inc.; Bojidar S

574 SEISMIC PERFORMANCE OF LONG-SPAN SUSPENSION BRIDGES M 1. INTRODUCTION This paper summarizes a... suspension bridges built in the United States between 1801 and 1994. The report, based on available information, is under review by the subcommittee. A long-span suspension bridge is defined as (me

SUBCOMMITTEE ON SEISMIC PERFORMANCE OF BRIDGES 575 Name of Bridge Location (state) Opened to Traffic in Main Span (meters) Age as of 1994 (years) Seismic Risk San Francisco-Oakland Bay California... St. Johns Oregon (2) 1932 368 62 Table 1 Data on 57 Long-Span Suspension Bridges

576 SEISMIC PERFORMANCE OF LONG-SPAN SUSPENSION BRIDGES Name of Bridge Location (state) Opened to Traffic in Main Span (meters) Age as of 1994 (years) Seismic Risk Crooked River Oregon (cont) 1963... Minnesota 1988 191 6 Table 1 Data on 57 Long-Span Suspension Bridges (coat.)

NH (O.min) m Ima JO,mod) Rl (2,mod) NJ ^ CT (O,mod) (O,mod) DE (2,min) MD (2,low) (no. of bridges, seismic risk based on ground shaking). neg: negligible, min: minor, mod: moderate, hgh: high, v-hgh: very high. See Table 2 for Classification of Seismic Risk. Fig. 2 No. of Long-Span Suspension Bridges and Seismic Risk in each State

578 SEISMIC PERFORMANCE OF LONG-SPAN SUSPENSION BRIDGES 3. SEISMIC RISK Since the seismicity and geology in the United States varies, bridges are subject to different seismic risks. Table 2 shows... Bridges, 1992) acceleration coefficients specified for each state. This is only a preliminary guide. As

le bridge; mais il suffit d'être bridgeur pour être considéré comme intelligent et apte à décrocher... annonces sont reçues jusqu'au jeudi à midi. A PROPOS DU BRIDGE Chacun sait que le monde comprend... les gens qui connaissent le bridge et il y aies autres. On n'est pas nécessairement calé et l'on

kleinere Wohnhäuser in Newport, North Bridge und Turra- murra sowie Appartementbauten zeugen von seiner.... Zweistöckiges Wohnhaus in North Bridge, Australien Habitation de deux étages à North Bridge, Australie Two-storey House at North Bridge, Australia Architekt: Harry Seidler, Sydney -% _«f I lisliiiil iii 1 y

with cupboards 16 Brücke / Pont Bridge 17 Überdeckter Außenspielplatz / Place de jeu couverte

EISENBETON LARGE GIRDER BRIDGES IN REINFORCED CONCRETE Le Congres a pu constater quel developpement... wide-span girder bridges. Increase in permissible stresses in consequence of improvements in material, and also the progress made in design and methods of construction, already enable bridges to be

the suitability of building larger trellis work bridges in reinforced concrete. The publication of the results of periodic observations of existing large girder bridges in reinforced concrete is greatly desired. ACTION DES CHARGES DYNAMIQUES SUR LES PONTS BR TICKEND YNAMIK DYNAMICS OF BRIDGES Au

individuals occupied with questions concerning the dynamics of structures (bridges, buildings, and

lila 2 Fatigue Strength and Safety of Welded Structures (Bridges, Structural Steel Work and Pressure Pipes). Ermüdungsfestigkeit und Sicherheit geschweißter Konstruktionen (Brücken- und Hochbauten und Druckrohre). Resistance ä la fatigue et securite des constructions soudees (Ponts, charpentes

piping and cast steel bodies, however it is rarely possible in bridges, and other structural steel

): Table 3. Structural Bridges Engineering4 A- Butl-welds. Tension 850 (l + 0,4 ^) — Fig. 16 — 1000..., Bruchstelle Rupture Fig. 6. Side fillet weld — Tension-fatigue test. 4 Applicable also to bridges if all the... consideration. At the same time the permissible stresses given under "Bridges" must not be exceeded

404 M. Ro5 Table 8. Bridge Construction. Rutt-welds in tension (Figs. 16 and 17) Stressed for: Stresses in kg/cm2 ö permissible ö-fatigue Oscillation strength öD 500 900 Surge load strength öu 850 1400 Alternating strength i/2 öw 1020 2000 ^ 1, yield öf 1200 2400 Mean value Factor of safety nr 1.80

Compression -9 ka mm Table 9. Bridge Construction. (Fig. 15) Stressed for: Stresses in kg/cm2 ö

: öozui 1200 kg/cm2 for bridges, or öorui 1400 kg/cm2 for other structural steel work10. (zul permissible

Fatigue Strength and Safety of Welded Structures 415 Bridge engineering is still in its infancy; in particular precaution has still to be exercised with lattice bridge constructions. Conditions are less complicated with plated constructions (girders, frames, arches). The problems with welded

IVb 2 Elimination of Bending Tensile Stresses in R. C. Bridges1. Ausschaltung der Biegezugspannungen bei Balken- und Stabbogenbrücken. Compensation des efforts de traction engendres par la flexion... bridges and halls grow steadily greater, for the tensile stresses in the concrete become considerably

bridge and hall building — prestressing has been adopted to a very considerable extent. The author's own process was first put into practice in 1928, in the construction of the 68 m span Saale Bridge

Elimination of Bending Tensile Stresses in R. C. Bridges 761 For this purpose the ties, eonstrueted of thick round steel bars, were placed in a trench and after straining were concreted to protect..., described in its application to an arch bridge constituting

invited for the Drei-Rosen-Brücke, a bridge in Basle (design Dyckerhoff & Widmann A.G.), Proposed a prestressed slab bridge. His projeet, as will be seen in Fig. 1, comprised arches cantilevering on... released. This form of bridge asproposed by U. Finsterwalder is also a strut frame system with

Elimination of Bending Tensile Stresses in R. C. Bridges 763 In large-span bridges and halls I find... bridges, elaborating the ideas of the German patent DRP 535440. The object of his endeavours is to... shrinkage. In this manner freely supported reinforced concrete girder bridges of up to 80 m span

obtained if we succeed in pre-stressing bridges in such a manner that only centric compression forces... contractions occur in the beams, so that under dead weight such a bridge would not undergo deflection

Elimination of Bending Tensile Stresses in R. C. Bridges 765 are set up without bending tensile... dead weight loading as a centrically loaded column. Let us now examine two girder bridges of very large span in which these ideas have been put into practice. 1) Gerber girder bridge with spans of

H "*/& ®? Fig. 2. Pre-stressed continuous hinged girder bridge. Fig. 3. Bending moments due to dead

Elimination of Bending Tensile Stresses in R. C. Bridges 767 Figs. 6 a — 6 c illustrate the shape.... * The Suspension bars are stressed while the bridge is being decentered. As a matter of fact the... weigth of the bridge to the Suspension boom, the anchors must be strained up to 1900 kg/cm2, giving for

Elimination of Bending Tensile Stresses in R. C. Bridges 769 must be very far up if a comparatively great degree of eccentricity of the compressive force is to be avoided. To do so, the lower part of the central rib is cut oi'f, as shown in Fig. 4, and the lower portions of the outer webs prevented

is of the same thickness as the decking slab. Thus the problem of reinforced concrete beam bridges

Elimination of Bending Tensile Stresses in R. C. Bridges 771 and creep to cause a very substantial drop in the stressing of the hanging trusses. Creeping and shrinking of, for instance, 40 • IO-5... points (ax) even after the bridge has been put into Service, so that the drop in stressing caused

of pre-stressed bridges is therefore extremely high, and for the following reasons: a) because the

Elimination of Bending Tensile Stresses in R. C. Bridges 773 c) The dead weight of these solid bridges is considerably higher than that of steel bridges, and consequently the\ are much less sensitive... slender bridges by live loading. They are calculated for a span 1 ¦= 70 m at 1/3160, for the cantilevering

cross beam to the other. The construction of the continuous bridge and the form of the hanging truss in Fig. 14 were executed in this manner. The bridge cross sections at mid-span are depicted in Figs... continuous Suspension boom is also very slight in the case of the through bridge, because this Suspension

r7g.ß* Zf/ffZift.Mf ^Thi^^ =W '208001m Fig. 11. Pre-stressed continuous girder bridge. Fig. 12. 12a.... Construction of bridge decking in the zone of negative moments due to dead weight. Fig. 18

stresses in these pre-stressed bridges is, as can be seen in Tables 2 and 3, the same as that with which we are familiär in arch bridges. In the latter the compressive stresses of arch action are... girder bridges the compressive force taking the place of arch action is artificially produced with

Elimination of Bending Tensile Stresses in R. C. Bridges 777 paragraphs we have attained exactly the same end for girder bridges as well. Under dead weight the beam did not undergo bending, nor was... the case of the arch bridge. Only a shortening of the axis of the beam occurred, owing to its centric

slender, the deflection under live load for the Suspension bridge in Fig. 19 is only 1/725, while in the Cologne- Mülheim bridge this value comes to 1/400. In this connection it sjhould be remembered that... therefore operative in transmitting live loads to the suppports. In the Suspension bridge shown in Fig. 19

. Fig. 23. Pre-stressed girder bridge with stiffening arch. n cd 7^ en

customarily done in steel construction, and the deflection of the bridge due to live load still further reduced. However, this is not necessary, for the deflections of these Suspension bridges in... closed when the tie is strained. Fig. 23 shows the cross section of a bowstring type bridge of 100 m

Elimination of Bending Tensile Stresses in R. C. Bridges 781 great extent. Tensile bars made of steel can easily be renewed in time to come; indeed, in girder bridges this Operation can even be carried out without putting the bridge out of service. The process of pre-stressing reinforced concrete

IVb 3 Wide-span Reinforced Concrete Arch Bridges. Weitgespannte Eisenbeton-Bogenbrücken. Arcs ä.... The construction of long span arched bridges in reinforced concrete, and the possibility of further... become considerably more important than is the case in bridges of medium span and this makes it

over the arch as a whole; future again looses its importance, because the dead weight of the bridge..., because the dead weight of the bridge itself considerably exceeds the live load and if the rise is... compression strengths in the concrete as high as 600 kg cm2; in the Traneberg bridge, for instance, the

Wide-span Reinforced Concrete Arch Bridges 785 missible stress in the concrete of 150 kg/cm2... available. In the construction of arch bridges of long span for which the design follows the pressure... jacks, when striking the false arch work. Point 1) is to be chiefly considered for small bridges. and

different Solution has been put forward by M.Ritter (International Congress on Bridge Construction

Wide-span Reinforced Concrete Arch Bridges 787 III. Closer calculation of arches and deformation theories. If the permissible stresses in arch bridges of long span are to be fixed as high as is... in the problem, and by more rigorous scrutiny of experiments carried out on large bridges it will be

by Prof. Dr. Ros on the Baden-Wettingen Bridge (Schweiz. Bauzeitung, 1929/1, 2nd March) disclosed variations in the elastic modulus across the bridge: in this pure arch strueture the value for Ec was

Wide-span Reinforced Concrete Arch Bridges 789 With load of 1 t/m over half the span: At left-hand springing, — 2210.00 tm, as against — 2092.6 tm, when E is constant A + 5.87o. At right hand... elastic modulus in an arch girder of hollow cross section. The construction of large arch bridges

Wide-span Reinforced Concrete Arch Bridges 791 the transition for an intermediate point x, y, cp can be calculated according to a parabolic» law, and at any given point in the arch: E9 I9 E I L*cpo I90 4 /L<(po I90 1 1 4 /L<cpo I90 1 *+f* p?"-^V_l X EI 1 \ EI / l l2 \ EI EI[A—Bx+ Dx2J. The axis of

Wide-span Reinforced Concrete Arch Bridges 793 transition for any given point x, y, cp referred to...) In a bridge with a large rise the difference between the loads gx and g can be very large, and for...-span bridge. To facilitate integration it has been deemed preferable to fix the origin of coordinates

Wide-span Reinforced Concrete Arch Bridges 795 The buckling load HK due to the horizontal force at... Mesnager has proposed 1/100 1. Maillart made the thickness of the füll arch in the Landquart bridge in..., and this applies of course toN long- spanned bridges. Safety against buckling must also be checked

anticipated lapse of time in constructing and closing the arch and completing the bridge, to form some

Wide-span Reinforced Concrete Arch Bridges 797 40 kg/cm2 amounts to II80/0 of the shrinkage value... will be 0.6 mm/m. In bridges of large span these relatively high values are, of course, important... reference to long span bridges there is still a need for really searching experiments on the amount

798 A. Hawranek In these bridges, therefore, the maximum stresses were only 57.5 and 76.9 kg/cm2; in the Plougastel bridge the maximum was 75 kg/cm2 and at La Roche Guyon 80 kg/cm2. | Fig. 2. The system thus provides a means for increasing the attainable span, and it allows of building a 500 m span

Wide-span Reinforced Concrete Arch Bridges 799 to an fixed arch. In the final strueture the line of... for further development of arch bridge construction, and one more will be described in Section VIII... long span bridges, representing as it does a significant part of the total cost of a reinforced

800 A Hawranek only instance of the use of steel centering in a reinforced concrete arch bridge of... no doubt that for fairly large spans (say up to 250 m) the use of timber must be confined to bridges... in the Roche-Guyon bridge of 161 m span — for it will scarcely be possible to adopt that method in

Wide-span Reinforced Concrete Arch Bridges 801 strueture. The relative advantage of any one such... having reference to the design of a bridge of 400 m span with cable construction of the same span... stiffened decking of the bridge. Such frames off er the further advantage that they could be used to

Wide-span Reinforced Concrete Arch Bridges 803 two parallel superimposed arches. The first of these would be concreted on centering; the centering would then be Struck and the first arch used as a support for building the second; finally both arches would be connected together so as to work as a

Wide-span Reinforced Concrete Arch Bridges 805 3) The bonded double arch. By reason of the jacks still existing within the bonded double arch, the latter is susceptible to stress-adjustments, as required, in aecordance with the loading later to be imposed. For this purpose the double hinges in the

, in a narrow bridge, stability can be increased by widening the corbel. The projecting portions can... marked in the case of bridges with a large rise, partly because in such cases the distance that the... details, commend it as a means for the construction of long span arch bridges in reinforced concrete.

Wide-span Reinforced Concrete Arch Bridges 807 Summary. The paper deals chiefly with the properties of materials as required in the construction of long-span arch bridges. It is ascertained that at... of reducing maximum stresses in arch bridges by means of correcting the axis of the arch is