SCP Tech Brief: Improving Freeze/Thaw Performance of Concrete
Spray-Lock Concrete Protection (SCP) technologies close capillary void space in concrete, significantly reducing permeability to liquids. Because of this action, the ability of liquid water to enter the concrete to then subsequently freeze and cause freezing/thawing damage is mitigated. This generally translates to longer service life of concrete in freeze/thaw exposure conditions.
When specifying SCP products as freeze/thaw improvement measures, consideration should be given to the potential routes of water ingress. SCP products should be applied to any surface of the concrete where water may potentially enter and cause subsequent freeze/thaw damage. To evaluate whether SCP products are the correct product to specify for freeze/thaw mitigation, the following test results from water permeability and freeze/thaw testing are provided for evaluation by the engineer of record.
Water Permeability Testing under Hydrostatic Pressure (EN 12390-8)
SCP technologies, when applied to new or existing concrete correctly, greatly reduce the ability of liquid water to penetrate the matrix. The following test results represent testing in accordance with EN 12390-8, a European norm that introduces water under 5 bar (72 psi) hydrostatic pressure to concrete for 72 hours and is an excellent indicator of concrete permeability.
Freeze/Thaw Durability Testing (ASTM C666)
The most recent freeze/thaw durability testing results are presented below.
Figure 1: Freeze/Thaw Testing Performance of SCP-Treated Concrete vs. Control
Damage from freezing and thawing is mitigated by reducing concrete’s permeability or the use of an appropriate air void system. By reducing water permeability, SCP products may sufficiently mitigate the potential for freeze/thaw damage of new and existing concrete. When specifying SCP products as a freeze/thaw mitigation measure for existing concrete, SCP recommends that pre- and post- treatment cores should be extracted and subjected to water permeability testing to verify that the treatment meets the requirements for low permeability concrete for freeze/thaw mitigation. For new concrete applications, SCP recommends following ACI guidelines for air entrainment volume percentage in addition to using SCP products for additional freeze/thaw protection.