Cares – an independent, non-profit-making certification body established to provide confidence to the users, purchasers and specifiers of reinforcing steels – has produced a guide to reinforcing steel in a bid to create greater awareness of reinforcing steel how is made, inspected, tested, or what characteristics it should have.

Cares operates a system of certification for reinforcing steel aimed at ensuring consistent compliance of products with appropriate product standards and customer specifications.
The organisation, which started its product certification scheme for reinforcing steels in the UK in 1984, has transformed the sector by minimising individual testing and bringing about a uniformity in product standards.
Prior to Cares, supply of reinforcing steels to the UK suffered a list of anomalies:
• The use of steel not complying with British Standards (BS) resulted in independent testing, which was expensive and often caused site delays;
• Misleading use and falsification of product test certificates;
• Excessive variability in mechanical properties;
• Ignorance of bar marking systems and an associated lack of material traceability; and
• Interface difficulties between supplier and customer;
As a first step, Cares set out to convince major construction clients, specifiers and contractors, how the use of its certification in specifications and quality management systems would provide the confidence to use such material with no further testing required.

Integrated approach
Because of a complicated supply route from steel mill to construction site (Figure 1), the Cares scheme covers the major elements of the reinforcement supply chain.
The current field of operation of Cares therefore includes the following areas:
• Carbon steel bars and coils;
• Stainless reinforcing steels;
• Processing, stockholding and supply of bar, coil and fabric;
• Cold worked wire;
• Welded fabric;
• Welded prefabrications; and
• Mechanical couplers.
In most of these areas, certification includes: product testing; quality system auditing; evaluation of manufacturers’ process capability; material and producer traceability, from hot metal through to the process of fixing it into the ground prior to concrete pour; and a feedback mechanism through an ongoing evaluation of customer complaints throughout the supply chain from mill to site, says Cares.

Sampling & testing
Product testing is central to all Cares assessments. Where activities influencing the specified properties of the steel are carried out – such as in the production of reinforcing bar, wire and fabric, product conformity assessment is applied by an analysis of the following:
• The supplier’s records of routine tests;
• Witness testing by the Cares assessor; and
• Testing of duplicate samples at an independent test laboratory.
The results of this testing regime are statistically analysed to establish variability in properties and to determine the degree of process control. This is key to the achievement of ongoing product compliance.
Producer & property traceability
Traceability provides the capability to locate materials that have emerged as problematic after despatch by the producer and to detect the source of both producer and problem. It also provides the fabricator and contractor with the test data to enable them to perform subsequent processing with the full knowledge of material properties.
Cares adopts a particular system of marking of the rolled reinforcing bar, coil or wire, whereby the Cares mark is rolled on, together with a series of dots, to identify the country and mill of origin (Figure 2).
In addition, approved firms are required to use the Cares logo and certificate number on all test and delivery documentation (Figure 3). The concept of Electronic Data Interchange (EDI) is now being pursued to minimise the use of hard copy and security of information is part of this process.

Cares list
The outcome of a satisfactory assessment is the issue of a Cares Certificate of Approval, with a closely-defined scope. The details of all approved firms and their scope of certification are published in a list, which is located, in an easily searchable form, on the Cares website: www.ukcares.com

Guide to reinforcing steel
For many specifiers and users, reinforcing steel is a commodity product, largely taken for granted. The most significant attribute is often the price, rather than any particular performance characteristic. Reinforcing steels are almost invariably ordered to national standards. Most designers will specify reinforcing steels using a bar or fabric schedules, with little knowledge about the product being ordered, how it is made, inspected, tested, or what characteristics it may have, and how these may influence fabrication, site operations and structural performance.
In order to help clarify this situation, Cares has produced a series of 10 articles, which together comprise the Cares Guide to Reinforcing Steels. These are:
• The product certification scheme for steel for the reinforcement of concrete;
• Manufacturing process routes for reinforcing steels;
• Properties of reinforcing steels;
• Fabrication of steel reinforcement;
• Welded reinforcement fabric;
• Pre-assembled welded reinforcement fabrications;
• Stainless reinforcing steels;
• Ancillary products for the reinforcement of concrete;
• Electronic labelling and transfer of data; and
• Reinforcement product standards and design codes.
These articles provide an overview of the reinforcing steel industry for clients, designers, engineers and contractors.