The Civil Engineering Contractor September 2018 | Page 30

INSIGHT
Repair material must be given sufficient open time for good placement .

Correcting structural repair

By Eamonn Ryan
The purpose of a structural repair is typically to restore concrete to its original purpose , be it a column , beam , or any concrete part of a structure that has become ‘ off spec ’, has been damaged , or has deteriorated .

According to EU stats , says Brian Dillon , director of Stanton Construction Chemicals , more than half of all structural repairs fail , with cementation being the overwhelming fault . He offers some practical tips on how to get your structural repair right the first time by proper assessment and workmanship .

“ Concrete repair is essentially a method of taking new repair material and adding it to older material by forming a multilayer composite system that will behave like a monolithic or single block , so it can handle the required service loads and environment . Why this is needed is because things do occur on site — in fact , there are an alarming number of repairs needed ,” explains Dillon .
Why repairs fail
In an ideal world , concrete would not fail if correctly prepared . Yet it does , due to the fact that a site has a large number of variables . For the same reason , repair jobs also often fail . Dillon spells out the most common reasons for the failure of repair actions as : incorrect design ; incorrect diagnosis of the root cause ; incorrect design of the subsequent repair ; incorrect choice of the applied repair material ; and poor workmanship — the provider ’ s technical data sheet .
28 - CEC September 2018