BS ISO 13918 Standards for Shear Connector Studs
Headed Shear Connector Studs from Artech meet the standards in every respect.
Shear connectors provide a powerful point of connection between two materials that are otherwise difficult to connect. Headed shear studs are deployed for effective shear transfer between concrete and steel in construction industry. An ideal shear connector must have three key attributes: ductility, strength and economy. Given below is a summary extract of standards pertaining to the Headed Shear Connector Studs.
Ductility in shear stud connector
Ductility is the ability of metal to be stretched thin or shaped into wire till its breaking point is reached. When shear studs are ductile, it means the structure will distort the structure. This will give prior warning before failure and allow redistribution of loads. The ductility requirements for a headed shear stud connector have been laid down in Part I of the AISC specifications brought out by the American Institute of Steel Construction. The document also specifies spacing limitations for connectors.
Shear stud connector design, strength and spacing
A standard practice is to use shear connectors that are stronger than the construction material they hold. That way, the structure will display deformities when it begins failing, and thus provide advanced warning of failure. Apart from the AISC, the Eurocode 4, the DIN standards and the Chinese National Code, also specify the design and strength requirements.
Design rules for shear studs are given in the Eurocode document EN 1994-2 document. Providing static strength and enable fatigue loading. The flow of shear force along the length of a girder varies. Limitations of the shear connectors need to be verified at Ultimate Limit State (ULS) and Serviceability Limit state (SLS). The Specifications lay down the requirements for SLS limit. Testing the SLS is critical in case of high-span bridges that have dead load component.
It is also specified that the distance between the edge of the shear stud and the edge of the flange plate should be 25 mm. However, many composite decks are now constructed using prefabricated framework. These frames have a 50mm seating length for which allowance needs to be made.
Testing of shear stud connectors
In England, specifications for testing of shear stud connectors are laid down by Highway Agency. These are followed in absence of comparable requirements in EN 1090-2. The fixing of the stud is checked by the ring test and band test. In ring test, the head of the shear stud is struck with a hammer. A ringing sound indicates that it is a good stud.
Where to find quality shear studs in India
The market for shear studs is price sensitive, and dominated mainly by imports. As Covid-19 disrupts supply chain, Artech is working to make quality shear studs and shear stud connectors available to domestic manufacturers at reasonable prices. The company has over the years emerged as one of India’s largest manufacturer of shear connector welding machines. Backed by state-of-the-art machines from Germany, the company is poised to ensure supply of quality stud connectors at reasonable prices.
The factory production control (FPC) in the standard specifies expectations from the manufacturer on several important areas. It requires a system with written procedures, routine inspections and tests and/or assessments, and the use of the results to control raw and other incoming materials or components, equipment, the production process and the product.
Typically, these procedures include guidelines on the following lines:
- General Manufacturing and Personnel
- Equipment testing and calibration procedures along with related documentation
- Design documentation at all stages of the process, along with testing and fault correction procedures
- Raw materials specifications to be documented along with the inspection scheme for ensuring their conformity
- In-process control plans to carry out production under controlled conditions.
- Product testing and evaluation procedures to ensure production tolerances are in conformity with the earlier in-process parameter. The tests include tensile strength, yield strength, elongation etc.
- Traceability and marking of Studs to be identifiable with regard to their production origin including documentation related to traceability codes and/or markings. The standards mandate to document the procedures of dealing with non-conforming products as well.
- Handling, storage, packaging procedures
- The standards also specify the detail tolerances for Studs, Ceramic Ferrules along with respective mechanical tests, chemical analysis and manufacturing finish