Stud anchors

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. 

In addition to the requirements of 3.3.7, anchor studs, such as J hooks, shall be welded to the underside of baseplate decks on maximum 300 mm (12 in.) centers to provide additional locking into the grout. 

In reformers and cracking furnaces firing at temperatures above 2,000° F, ceramic cups are used instead of alloy clips to retain the blanket. The alloy stud tip is recessed about VA inches into the lining. The cup is filled with ceramic fiber putty to protect the stud from the furnace temperature and to lock the retainer securely to the anchor. 

Lawless HT, Cardello AV, Chapman KW, Lesher LL, Given Z and Schutz HG. (2010) A Comparison of the effectiveness of hedonic scales and end-anchor compression effects. J Sens Stud, 25 18-34. 

By virtue of its basic size and the relative thinness of its component make-up a liner requires continuous structural support in all directions in order to withstand the loading from thermal and pressure conditions in a reactor and still remain Impermeable. Present liners are therefore usually firmly attached to and fully supported by the concrete structure of the PCRV. Due to this positive attachment, the liner is subjected to the stresses and strains Imparted to it by the PCRV during initial prestressing and, later, by movements of the PCRV due to the operating condition of the reactor. To ensure even distribution of these movements across the full size of the liner, attachment of the liner to the concrete is achieved by the embedment of a combination of steel sections and a multitude of studs or hook anchors. See figure 9. 

The design development of steel liners for PCRVs over the years has led to the currently acceptable principle of bonding the liner to the concrete with a multitude of closely spaced stud or hook anchors. 

To anchor the sheet mechanically, non-penetrating rivets are used to fix the membrane, particularly on sloped roofs or steep surfaces. Polyamide studs are fixed to the deck with an EPDM rubber cap and metal clip. Spacing of the studs depending on the expected wind lift, and the covering is then placed over the fixed studs. With the help of proper lubricants, caps are secured to the studs with a fastener tool and the perimeters can be secured with adhesive. 

V-draining. See double-draining. V-Stud. A V-shaped stud or anchor for a refractory lining. 

Y-Stud. A piece of round or rectangular section metal, Y-shaped, used to anchor a refractory lining. 

The end anchor assembly for the soil nails should be covered by the finished layer of shotcrete. It is a common practice to install steel studs on the end bearing plate for typical application. These studs can help ensure a sufficient connection between the temporary layer of shotcrete and the final shotcrete layer, while also increasing the punching shear capacity. 

Note The value of the 14.3 t from standard tests on anchors by Nelson company on 5/8" size studs. If 12.7 tons anchor value is taken, the value of Ax will reach about 2". 

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. 

Klingner, R.E., and J. A. Mendonca, (1982a), Tensile Capacity of Short Anchor Bolts and Welded Studs A Literature Review, ACI Structural Journal, Vol. 79, No. 4, pp. 270-279, 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. 

Tables 2.1a b list the ASTM specifications, yield strengths, ultimate strengths, and range of available diameters for materials commonly used for anchor bolts and studs, and threaded anchor rods, respectively. Unless the anchors are to be used in a special corrosive environment or are subjected to extreme low or high temperatures or other special conditions, the following specifications should be used ...

Table 2.1a Common Materials for Anchor Bolts and Studs...

Note SeeACI 355.3R-11, Appendix A-Tables A2 for cast-in-place anchors, threaded rods widi nuts, threaded rods with nuts and washers, and the dimensional properties of bolts, studs and nuts for determining bearing area(Ai,rg). 

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. 

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