What causes the problem?

Over the past 20 years the causes of deterioration in reinforced concrete have become more clearly understood. Once the steel reinforcement begins to corrode it expands exerting massive stresses on the protective concrete cover. This leads to rust staining, cracking and eventually large scale spalling.

DPC LTD are specialist in the following two key mechanisms that accelerate this process –

Carbonation – Ingress if CO2 (and other acidic gases) reduces the pH of the concrete. Over time this carbonation front eventually reaches the reinforcement and destroys the important alkaline passivation/protection of concrete. In the presence of O2 and water the normal rusting process can then occur.

Chloride Ions – The presence of CI ions has been shown to be especially damaging. Not only do they accelerate the rate of carbonation they can electrochemically induce localised corrosion pitting and severe reduction in the cross-sectional diameter of the reinforcement.

Both these processes are more aggressive when combined with physical problems associated with poor workmanship and design during the initial construction phase.

In particular, inadequate concrete cover, due to poor placement of steel, or badly placed and compacted concrete is especially damaging.

What services DPC LTD can offer …

  • Flexible systems – hand application, pourable and wet and dry spray process
  • High performance medium weight concrete reinstatement mortar
  • High performance lightweight concrete reinstatement mortar
  • Polymer modified concrete reinstatement mortar for high build applications
  • Polymer modified structural concrete repair mortar
  • Corrosion control in reinforced concrete
  • Reinstatement mortar for concrete pavements and floors
  • Fairing coats
  • Rapid setting cementitious bedding mortar
  • High flow, shrinkage compensated rapid setting grout
  • Polyester resin mortar for bedding road ironwork where heavily trafficked
  • Rapid setting concrete
  • Technical advice on all problems / specifications
  • Extensive knowledge providing the right solution
  • Shrinkage compensated repair mortars
  • Excellent bond to host concrete