What is CD534 Specification? And why is it important when carrying out ironwork reinstatements?

What is CD534 Specification

What is CD534 specification, is a common question. This specification covers the bedding mortars for use on irons works. National Highways recently updated the Design Manual for Roads and Bridges (DMRB) in 2020.

For more than twelve years, HA 104/09 (an 'advice note' within the DMRB) has been a key document for chamber tops and gully tops, setting out procedures and denoting materials that Highway Authorities believe provide the best possible performance for installations in trunk roads and motorways.

This HA 104/09 advice note has been replaced by CD 534, a new Technical Regulation posted and referenced on the European Commission Technical Regulation Information System (TRIS) website.

An element of the newly documented CD534 is bedding mortar which must have a compressive strength of plus >30N/mm2 and tensile strength of >5N/mm2. The HardMaster W620 and W621 polymer modified mortar have superior compressive, tensile, and flexural strengths, which meets the demands in this new CD534 document.

The W620 and W621 are environmentally friendly alternatives to resin-based materials specifically formulated for all access covers' bedding. Ideal it is used in heavily trafficked locations. The major benefit to the product is that it can be open to traffic after just under 1 hour. This also helps with local authorities with those expensive road closures.

HardMaster W620 is a high-strength bedding mortar that has exceptional performance in wet conditions. It has a guaranteed cure, as it is a two-component product and achieves strengths of  40N/mm2 in 3 hours. It is designed for bedding of inspection chamber frames/covers.

HardMaster W621 HA104 flowable mortar is a two-component high performance mortar. It contains the benefits of resin-based materials with the ease of use of cementitious materials. It is designed for the rapid installation and reinstatement of highway furniture and provides exceptional performance in wet weather conditions.

HardMaster Specification

If you want to know more about these products, take a look at our ToolBox Tips Video – How to utilise our defect-free HardMaster CD534.