Continuity strips are one of the many reinforced concrete products and systems in the market that are not covered by national or international product standards. However, users of these bespoke products and systems need to have the same level of product quality assurance that they would expect for rebar, a safety critical structural material.
A reinforcement continuity strip is designed to maintain continuity across construction joints in concrete structures in a time saving and cost efficient manner. It consists of reinforcement that is pre-bent and housed in a purpose-designed carrier casing.
On the construction site, this unit is secured into a wall or floor in advance of the concrete pour. Once secure, the lid of the unit is removed to reveal the connection legs (in CARES-approved systems, steel bars that meet the requirements of BS 4449 as well as the specific requirements of the approval) which can be bent out using a specially designed tool ready for splicing with the main reinforcement of the consequent concrete pour.
The CARES Technical Approvals scheme provides product certification for continuity strips as well as other structural products including mechanical couplers and punching shear systems. It is open to all manufacturers that demonstrate compliance with the requirements and provides a process for assuring the quality of non-standard or new and innovative products.
Don Houston, Construction Director at the Byrne Group says, “We place high value on assurance provided by the CARES Technical Approval scheme for reinforcement continuity systems and other structural reinforcement products.”
The National Structural Concrete Specification (NSCS), clause 6.1.4, also recognises the structural importance of continuity strips and advocates the use of products with a valid CARES Technical Approval certificate. However, a significant proportion of the continuity strip market is serviced by non-approved products.
Even a continuity strip that may contain CARES-approved rebar is not the same as a continuity strip with CARES Technical Approval and therefore does not have the same level of product assurance. In order to obtain technical approval, producers of continuity strip have to undergo a comprehensive testing programme managed by CARES with products being independently tested at least twice per year. CARES also carries out in-situ structural testing to evaluate the performance of construction joints under loading.
There are currently four CARES-approved continuity strips on the market:
1) Eazistrip (produced by Ancon)
2) Ferbox (Invisible Connections)
3) Kwikastrip (Halfen)
4) Startabox (RFA-Tech).