ENGINEERS IN Oklahoma last week confirmed that they had launched a full appraisal of bridge pier protection following last month's fatal bridge bash (NCE 30 May).
A section of the bridge carrying the Interstate 40 motorway collapsed after a barge travelling upstream struck unprotected piers outside the main shipping lane. The bridge's only protection against barge impact was on the upstream side of the piers immediately next to the shipping lane.
Oklahoma Department of Transportation (ODT) bridge manager Tim West said: 'A full report is being undertaken to evaluate the risk from errant barges following the barge impact that caused last month's disaster.'
US contractor Gilbert Central Corporation won the 120 day, £7.5M repair contract after an emergency Oklahoma Transport Commission meeting last week.
The contractor has 57 days to get traffic moving again across the Arkansas river. Barges holding up the section of highway hanging from the bridge deck after it fell onto them were removed last week and the replacement of the missing 35m section of deck is set to start.
Replacement piled foundations will have to be driven outside the remains of the existing structure. These new piers will again be twin columns rather than the full width piers supporting the rest of the structure. No extra protection against barge collision will be added.