Headed studs

Headed studs are manufactured from low carbon steel in accordance with ASTM A108. They have a minimum yield strength of 50 ksi (345 MPa) and a minimum specified tensile strength of 60 ksi (414 MPa). 

Post-installed anchors are manufactured in a variety of materials. A detailed discussion of post-installed anchors is presented in Chapter 4. The engineer should consult the manufacturer of proprietary systems for materials used, and select the most appropriate material for the intended use of the anchor and the environment in which it will be used. 

---

ALL HEAD STUDS AND NUTS are external and accessible without removal of valves to reach internal bolting. There is no possibility of hidden internal leakage. 

Headed studs are normally used to secure a roof slab to a structural steel framing system for rebound loads in new designs. This option may not available for upgrading existing structures. It may be necessary to provide through bolts to the structural frame with a backing plate on the top side of the stab. 

Reactor head studs and reactor recirculation pump casing studs are inspected ultrasonically every refueling outage and their threads are examined visually. No degradation has been observed. 

Provides support for the vessel head stud tensioner-detensioner during refuelling. 

Furche, J., and R. Eligehausen (1991), Lateral Blowout Failure of Headed Studs Near a Free Edge, Anchor is Concrete Design and Behavior, SP 130, American Concrete Institute Farmington Hills, MI. 

This chapter provides the basic materials, properties, and corrosion protection recommendations for holt and rod assemblies, headed studs, post-installed anchors, and shear lugs. The engineer must select the proper material, considering properties such as grade, yield strength, tensile strength and weldability and provide for corrosion resistance so that the anchorage will perform as required and intended. 

Steel embedded plates are often used to transfer loads from structural members to concrete structures or foundations. Such plates are often cast-in-place for constructability and to provide a smooth surface for attachment. These plates are attached to the concrete with welded anchors, which typically consist of headed studs, headed anchors, weldable rebar, or shear lugs they can be designed to resist applied tension, shear, and moment. Welding should be compatible with the anchor type. 

AWS Dl.l/Dl.lM requires studs to be Type B made from cold drawn bar stock conforming to ASTM A108. Since headed studs are relatively short, it is not practical to consider reinforcing steel in design as might be the case with longer anchors. 

Headed anchor rods may be used in heu of headed studs to increase the embedment and assure ductile design, or if studs are not available. Design is similar to that for headed studs. The user must ensure that the anchor rod is made of a weldable material. 

Equation (D-I9) is for cast-in headed stud anchors. It is based on the fixity of the anchor to the embedment and is appropriate for use in designing anchors welded to embedded plates. 

---