(a) Connections of precast members
(b) Connections between foundations and either cast-inplace or precast members
(c) Horizontal shear strength of composite concrete flexural members
(d) Brackets and corbels
(a) Connections between precast columns shall have vertical integrity ties, with a nominal tensile strength of at least 200Ag lb, where Ag is the gross area of the column. For columns with a larger cross section than required by consideration of loading, a reduced effective area based on the cross section required shall be permitted. The reduced effective area shall be at least one-half the gross area of the column.
(a) Longitudinal and transverse integrity ties shall be provided in floor and roof systems to provide a nominal tensile strength of at least 1500 lb per foot of width or length.
(c) Longitudinal and transverse integrity ties shall be positioned in or within 2 ft of the plane of the floor or roof system.
(d) Longitudinal integrity ties shall be oriented parallel to floor or roof slab spans and shall be spaced not greater than 10 ft on center. Provisions shall be made to transfer forces around openings.
(f) Integrity ties at the perimeter of each floor and roof, within 4 ft of the edge, shall provide a nominal tensile strength of at least 16,000 lb.
(a) Integrity ties shall be provided in all wall panels and shall be continuous over the height of the building.
(b) Integrity ties shall provide a nominal tensile strength of at least 3000 lb per horizontal foot of wall.
(c) At least two integrity ties shall be provided in each wall panel.
Table 220.127.116.11—Minimum design dimensions from face of support to end of precast member
|Member type||Minimum distance, in.|
|Solid or hollow-core slab||Greater of:||ℓn/180|
|Beam or stemmed member||Greater of:||ℓn/180|
(b) Any calculated tensile force across the interface
(a) Base of structural steel section shall be designed to transfer the total factored forces from the entire composite member to the foundation.
(b) Base of structural steel section shall be designed to transfer the factored forces from the steel core only, and the remainder of the total factored forces shall be transferred to the foundation by compression in the concrete and by reinforcement.
|ϕSn ≥ U||(18.104.22.168)|
where Sn is the nominal flexural, shear, axial, torsional, or bearing strength of the connection.
(a) Dowels shall not be larger than No. 11
(b) Dowels shall extend into supported member at least the greater of the development length of the longitudinal bars in compression, ℓdc, and the compression lap splice length of the dowels, ℓsc
(c) Dowels shall extend into the footing at least ℓdc of the dowels
Table 22.214.171.124—Nominal horizontal shear strength
|Shear transfer reinforcement||Contact surface preparation||Vnh, lb|
|Av ≥ Av,min||Concrete placed against hardened concrete intentionally roughened to a full amplitude of approximately 1/4 in.||Lesser of:||(a)|
|Concrete placed against hardened concrete not intentionally roughened||80bvd||(c)|
|Other cases||Concrete placed against hardened concrete intentionally roughened||80bvd||(d)|
Concrete contact surface shall be clean and free of laitance.
|ϕVnh ≥ Vuh||(126.96.36.199)|
Nominal horizontal shear strength Vnh shall be calculated in accordance with 188.8.131.52 or 184.108.40.206, where area of contact surface shall be substituted for bvd and Vuh shall be substituted for Vu. Provisions shall be made to transfer the change in compressive or tensile force as horizontal shear force across the interface.
(b) (480 + 0.08f'c)bwd
|Nn = Anfy||(220.127.116.11)|
(a) A weld to a transverse bar of at least equal size that is designed to develop fy of primary tension reinforcement
(b) Bending the primary tension reinforcement back to form a horizontal loop
(c) Other means of anchorage that develops fy