Head stud
A headed bolt , also known as a headed bolt dowel , is a steel pin with a mushroom-shaped head and is used in composite steel construction to create an anchoring between concrete and steel . The geometry of the bolt creates a good bond and thus good power transmission. Head bolts are therefore the most common type of anchoring. As a rule, common structural steels are used , as in the case of the steel structure to be anchored, with at least the same or higher strength.
Areas of application
Composite construction
In composite construction and if both of the following conditions are met, the dimensions according to the technical building regulations introduced in accordance with Section 3 (3) BauO NRW can be used:
- There is no planned loading of the dowels in their longitudinal axis by tensile forces.
- The transmission of the loads from the contact joint between the anchor plate and the concrete surface takes place with the formation of an idealized framework system in the concrete component with full coverage of the tensile forces by slack reinforcement. For this purpose, detailed static evidence must be provided.
In the case of pure anchor plates or transition structures , the transmission of tensile forces is also permitted.
The anchoring or connection of steel parts by means of welded-on headed bolts must be dimensioned in accordance with a general building approval from the German Institute for Building Technology or the European Technical Approval .
The head stud dowel may only be attached to a composite component by means of arc stud welding (welding process 783 according to ISO 4063) with a stud welding system. The company carrying out the work must be in possession of a corresponding welding certificate in accordance with EN 1090, and the operating personnel must have a valid operator test in accordance with EN 1418 or ISO 14732.
Other uses
Head bolts are used in pure reinforced concrete e.g. B. as an anchoring means for anchor plates that are to lie in a concrete surface. They are also part of special punching shear reinforcement elements (dowel bars) for reinforced concrete slabs.
Regulations in composite construction
- General design rules, design rules for building construction, (February 1994 edition) in conjunction with DAST guideline 104; Guideline for the application of DIN V ENV 1994 part 1-1
- DIN 18800-5, yellow print January 1999 Steel structures Part 5: Composite structures made of steel and concrete, dimensioning and construction
- DIN 18806-1, composite structures, composite columns (edition March 1984)
- DIN-Fachbericht 104, composite bridges (edition March 2003)
- Eurocode 4 Part 1-1: Dimensioning and construction of composite girder structures made of steel and concrete - General design rules and application rules for building construction
- Eurocode 4 Part 2: Design and construction of composite steel and concrete structures - General design rules and application rules for bridges
- Guideline for the design and execution of composite steel girders (March 1981 edition) with the supplementary provisions (March 1984, June 1991)