Latest Crimean bridge attack came from below, according to expert analysis

The damage caused to the Crimean Bridge in the latest attack is likely to have been caused by an explosion from below and leave it out of action for weeks, according to a blast expert.

The 17km Crimean bridge, which connects Krasnodar in Russia with Kerch in Crimea, is two separate but parallel bridges carrying road and rail. It suffered damage to its road carriage during an attack in the early morning of Monday 17 July which killed two and injured a child.

It is the second time the bridge has been attacked during the conflict between Russia and Ukraine, following a massive explosion last October, which was set off by a truck crossing the bridge. The force of the explosion saw several spans plummet into the water below and a tanker on the parallel railway catch fire. The damage was extensive, but Russia worked at pace to bring the roadway back into use ahead of schedule, as it is crucial to the war effort. However, work to replace the rail bridge was more difficult.

The damage caused to the Crimean Bridge by the latest attack is not as widespread, but it is on a section of the bridge that it closer to the water’s surface and the blast was enough shear through the deck and leave a section dangling into the sea.

A video shows a section of road on the damaged bridge between Russia and Crimea sloping to one side after an incident killed two people https://t.co/Z1quO5arCT pic.twitter.com/gznNGHTPB0

— Reuters (@Reuters) July 17, 2023

As with the previous Crimean Bridge attack, the method and culprit have not been ascertained, but Russia has claimed that Ukraine used water-based drones to carry out the operation.

Looking at the damage caused by this latest explosion in the released images, University of Sheffield department of civil engineering blast and impact dynamics research fellow Andrew Barr said that it seems “very consistent with an explosion underneath the bridge”. He added: “this part of the bridge is relatively low, so it’s possible that an explosive device could have been delivered using a drone on the water’s surface”.

Analysis previously carried out by Monash University associate professor of civil engineering Colin Caprani and University of Sheffield senior lecturer in blast and impact engineering Sam Rigby has identified the road bridge as being a composite slab orthotropic deck, supported on 3.2m deep steel plate girders over the 64m span between its concrete piers.

“The momentum imparted to the road deck by the explosion appears to have been sufficient to lift it up off its bearings at the expansion joint and displace it several metres to the side,” Barr said. “This has left the southbound lane only partially supported by the concrete pier, and severely twisted. The northbound lane has also shifted to a smaller degree, so that the bridge is currently impassible in both directions.”

Looking at the spread of the damage, he added: “Images show localised damage and cracking of the concrete deck, and loss of the steel access gantries underneath the deck. There also appears to be some damage to the structural steelwork, though it's difficult to say how extensive this is from the current images.”

Russia will again look to bring the road bridge back into operation as soon as possible, but it will not necessarily be a quick fix. “Depending on the level of damage, it may be possible to repair and reposition the northbound lane, but the southbound lane is likely to require a full replacement,” Barr said. “This could follow a similar pattern to the reconstruction last year, with cranes on barges used to place prefabricated replacement spans.”

He added: “The timescales required for this work may be aided slightly by the recent experience of repairing the bridge, but is still likely to be weeks before the bridge is fully opened to traffic.”

The Crimean Bridge is of particular importance to Russian president Vladimir Putin, who ordered its construction upon successfully annexing Crimea from Ukraine in 2014. Upon its completion in 2018, he drove a truck across it in celebration. It quickly became an important route for sending supplies to Crimea and since the war started it has also been crucial for sending Russian forces into southern Ukraine.

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