CIVIL ENGINEERING AND CONSTRUCTION
Continuous sequence
The main compound is at the Grange (western) end of the viaduct, with the old decks being taken out that way. The crane is at the eastern, Arnside end, where the new decks are arriving on a low-loader. They
are then lifted up onto the structure, before a gantry crane places them in position.
That procedure is copied from that used during the Leven viaduct works – a similar structure, also in Cumbria, originally built at a similar time and in a similar way.
Henshaw said: “The gantry crane can run in the troughing grooves, so there’s no special mechanism needed; we can just erect it, place it into the new grooves and it runs on rollers.”
There are investigative works taking place to see if additional scour protection works on the piers below should be done during the current set of works, instead of having to come back and do them in a few years’ time. There are also additional maintenance works during the blockade, to fully utilise that opportunity. These have included repairs to the brickwork and the pier concrete. The piers themselves, Henshaw said, were in “remarkably good” condition considering their age and the harsh environment they must withstand. Other works have included improvements to Lindal tunnel, which was shortened by 25 metres through hillside ‘reprofi ling’.
Walkway
The viaduct rebuild has also raised the prospect of a walkway for pedestrians and cyclists, which is not included in the current set of works but has long been a wish for those living in the area.
Henshaw said everyone from local rail user groups, the council and Sustrans wanted the walkway. She explained: “We’ve had a lot of interest from different people, not in sole funding it, but perhaps in contributing. It’s now about who’s going to co-ordinate that with regards to funding, ownership, asset management and maintenance. It’s a strong possibility it could happen, with the new walkway cantilevered off the side.”
56 | rail technology magazine Apr/May 11
A long way to go
When RTM talked to Henshaw, four of the decks had been laid – with 98 still to go. The works were four days behind schedule, but she said the deck-laying had been going brilliantly so far, with each “fi tting like a glove”.
She added: “As you actually land each deck, the pallet of VIPAs are on that deck – reducing the amount of manual handling needed. They are then placed out and the rails installed, then we re-start the process on the opposite side, all the time making sure we’ve got those edges protected.
“We’ve had a lot of lessons learned from doing Leven viaduct – we took a lot of information from the ‘lessons learned’ meeting they held after that project, during which 24-hour working had to be implemented because it fell behind programme.”
There are 40 engineers working on the viaduct at peak times, using a token system so the project managers know who and how many.
Work has been carrying on despite the tides, although if there’s a major storm, works will be postponed.
Unsurprisingly, health and safety has been an important factor in preparing for the works – not only the constant emphasis on securing the edges of the working area with handrails and barriers, but also contingencies in case of emergencies.
One such example is the jet ski that the Coastguard has on stand-by: just in case anyone does fall in the water.
FOR MORE INFORMATION
To see an animation showing exactly what is going on at Arnside, visit www.
railjobsblog.com/arnside-viaduct.htm
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164 |
Page 165 |
Page 166 |
Page 167 |
Page 168 |
Page 169 |
Page 170 |
Page 171 |
Page 172 |
Page 173 |
Page 174 |
Page 175 |
Page 176 |
Page 177 |
Page 178 |
Page 179 |
Page 180 |
Page 181 |
Page 182 |
Page 183 |
Page 184 |
Page 185 |
Page 186 |
Page 187 |
Page 188 |
Page 189 |
Page 190 |
Page 191 |
Page 192 |
Page 193 |
Page 194 |
Page 195 |
Page 196 |
Page 197 |
Page 198 |
Page 199 |
Page 200 |
Page 201 |
Page 202 |
Page 203 |
Page 204 |
Page 205 |
Page 206 |
Page 207 |
Page 208 |
Page 209 |
Page 210 |
Page 211 |
Page 212 |
Page 213 |
Page 214 |
Page 215 |
Page 216 |
Page 217 |
Page 218 |
Page 219 |
Page 220 |
Page 221 |
Page 222 |
Page 223 |
Page 224 |
Page 225 |
Page 226 |
Page 227 |
Page 228