The Design of Modern Steel Bridges - TEDI

Recommendations

Info

6 The Design of Modern Steel Bridges Figure 1.7 Clifton Suspension Bridge, England (1850–64). Figure 1.8 Albert Bridge over the Thames, England (1864–73).
Types and History of Steel Bridges 7 its deck had to be replaced in 1839, 1893 and again in 1939. Telford also built the 327 ft (100 m) span suspension bridge at Conway for the same Holyhead Road at about the same time. The success with these two suspension bridges brought about a new era of long-span bridges. Isambard Kingdom Brunel built Hungerford pedestrian suspension bridge over the Thames at Charing Cross which, however, had to be removed 20 years later to make room for the present railway bridge. William Clark built Hammersmith Bridge, Norfolk Bridge at Shoreham, the bridge at Marlow over the Thames and the 666 ft (203 m) span bridge over the Danube at Budapest – all suspension bridges. Several other suspension bridges with wire cables were built in Europe, the most remarkable being the Grand Pont at Fribourg, Switzerland, by Chaley, which had a 800 ft (244 m) span supported by four cables each of 1056 wires, 3 mm diameter. A competition was held for the design of a bridge over the Avon Gorge at Clifton, Bristol. Brunel submitted a design for a suspension bridge of 1160 ft (354 m) span. Telford was a judge for the competition and did not consider such a long span practicable. In a second competition in 1850, Brunel’s design of a 600 ft (183 m) span was accepted. Work started but was abandoned due to the contractor going bankrupt. In 1860, a year after Brunel’s death, work was resumed with some changes in the design and completed in 1864; the chains of Brunel’s Hungerford bridge were reused here – they had wrought iron shafts with eyes welded to their ends by hothammering. This beautiful bridge is still carrying vehicles – a great testimony to a very great engineer. By the middle of the nineteenth century, good-quality wrought iron was being produced commercially, replacing cast-iron for structural work and being used extensively for shipbuilding. This material was ductile, malleable, strong in tension and could be riveted. William Fairbairn had already designed a riveting machine. In the second half of the eighteenth century, the coal industry in England was using steam engines for pumping out water, and wooden or iron rails for moving coal wagons. In the first decade of the nineteenth century, several collieries around Newcastle had steam boilers on wheels running on rails by means of ratchet wheels for hauling coal wagons. In 1814 George Stephenson built an engine which did not need any ratchets to run on iron rails. In 1825 Stephenson’s Rocket engine ran on the Stockport-to-Darlington railway. This railway was followed by Manchester–Liverpool and London–Birmingham railways. Soon railways grew all over Britain, then in Europe and North America. This produced an insatiable demand for bridges (and tunnels), but these bridges had to be sturdy enough to carry not only the heavy weight of the locomotives, but also their severe pounding on the rails. They also had to be built on a nearly level grade; otherwise the locomotives could not pull the wagons up. George Stephenson built two types of bridges for his railways – a simple beam of cast-iron for short spans over roads and canals, and cast-iron arches for longer spans. The most striking example of the latter type was the
Page 1: The Design of Modern Steel Bridges
Page 5 and 6: The Design of Modern Steel Bridges
Page 7 and 8: Contents Preface vii Acknowledgemen
Page 9 and 10: Preface Bridges are great symbols o
Page 11: Acknowledgements The figures in Cha
Page 14 and 15: 2 The Design of Modern Steel Bridge
Page 22 and 23: 10 The Design of Modern Steel Bridg
Page 58 and 59: Table 2.1 Properties of some commer
Page 63 and 64: Chapter 3 Loads on Bridges 3.1 Dead
Page 65 and 66: 3.3 Design live loads in different
Page 67 and 68: interstate highways are designed fo
Page 69 and 70:
a coefficient that depends on the n
Page 71 and 72:
Loads on Bridges 59 In Germany, a n
Page 73 and 74:
Table 3.6 Typical values of U and P
Page 75 and 76:
3.5 Longitudinal forces on bridges
Page 77 and 78:
wind loading on the traffic. An upl
Page 79 and 80:
where r is the air density ¼ 1.226
Page 81 and 82:
Loads on Bridges 69 minimum and max
Page 83 and 84:
3.8 Other loads on bridges There ar
Page 85 and 86:
References Loads on Bridges 73 wher
Page 87 and 88:
Chapter 4 Aims of Design 4.1 Limit
Page 89 and 90:
critical components of the structur
Page 91 and 92:
But this is an attempt to achieve u
Page 93 and 94:
If the basic variables R and S are
Page 95 and 96:
educed variables defined by oi ¼ x
Page 97 and 98:
will have a probability of failure
Page 99 and 100:
Aims of Design 87 g m ¼ g m1 g m2
Page 101 and 102:
Table 4.2 Failure probabilities of
Page 103 and 104:
Chapter 5 Rolled Beam and Plate Gir
Page 105 and 106:
as possible. But deep and thin webs
Page 107 and 108:
eam, with an effective area equal t
Page 109 and 110:
and stresses caused by lateral defl
Page 111 and 112:
Figure 5.3 Beam cross-section. In t
Page 113 and 114:
Rolled Beam and Plate Girder Design
Page 115 and 116:
Table 5.2 Effective length factors
Page 117 and 118:
stress is equal to p 2 E/(Le/r) 2 )
Page 119 and 120:
equation (5.16) has been adopted fo
Page 121 and 122:
The strain energy of the elastic re
Page 123 and 124:
Figure 5.6 Buckling of plates in co
Page 125 and 126:
Figure 5.8 Buckling of plate under
Page 127 and 128:
techniques. It may be noted that th
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
5.4.3 Effect of residual stresses R
Page 135 and 136:
Aw ¼ 40 mm 2 , allowing for a smal
Page 137 and 138:
Page 139 and 140:
Page 141 and 142:
Basler and Thurlimann were the firs
Page 143 and 144:
Ostapenko/Chern gave the following
Page 145 and 146:
where m ¼ Mp b 2 twsyw ty ¼ syw p
Page 147 and 148:
the case of equal flanges, the tota
Page 149 and 150:
emains flat until an elastic critic
Page 151 and 152:
Page 153 and 154:
longitudinal compression is given b
Page 155 and 156:
where Peq ¼ s1tB PE Ps Pcro Peq1
Page 157 and 158:
Figure 5.27 Tension-field forces in
Page 159 and 160:
5.5.6 Design of longitudinal web st
Page 161 and 162:
when Le is the effective length for
Page 163 and 164:
pffiffiffiffiffiffiffiffiffiffiffif
Page 165 and 166:
een derived as a condition for trea
Page 167 and 168:
For interaction of various stress c
Page 169 and 170:
must be at least i.e. 1 IsxbB 4 2 a
Page 171 and 172:
Chapter 6 Stiffened Compression Fla
Page 173 and 174:
Stiffened Compression Flanges of Bo
Page 175 and 176:
cross-section in which the secant s
Page 177 and 178:
longitudinal compression of the lon
Page 179 and 180:
webs of main girders is denoted by
Page 181 and 182:
Page 183 and 184:
wherefrom Ms ¼ 2 3 PE P The net be
Page 185 and 186:
Page 187 and 188:
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
Chapter 7 Cable-stayed Bridges 7.1
Page 197 and 198:
Cable-stayed Bridges 185 cables con
Page 199 and 200:
The following is a list of cable-st
Page 201 and 202:
(a) Fan system (b) Harp system (c)
Page 203 and 204:
7.3.2 Ropes causing lateral compres
Page 205 and 206:
The spiral winding of wires around
Page 207 and 208:
polyethylene or even steel tube. Or
Page 209 and 210:
See Fig. 7.7. Imagine a cable-stay
Page 211 and 212:
It may be noted that: Et is higher
Page 213:
Reference Cable-stayed Bridges 201
Page 216 and 217:
204 The Design of Modern Steel Brid
Page 218 and 219:
206 The Design of Modern Steel Brid
show all

The Design of Modern Steel Bridges - TEDI

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?