1808.8 Concrete Foundations
Where concrete is placed through a funnel hopper at the top of a deep foundation element, the concrete mix shall be designed and proportioned so as to produce a cohesive workable mix having a slump of not less than 4 inches (102 mm) and not more than 8 inches (204 mm). Where concrete or grout is to be pumped, the mix design including slump shall be adjusted to produce a pumpable mixture.
|FOUNDATION ELEMENT OR CONDITION||SPECIFIED COMPRESSIVE STRENGTH, f 'c|
|1. Foundations for structures assigned to Seismic Design Category A, B or C||2,500 psi|
|2a. Foundations for Group R or U occupancies of light-frame construction, two stories or less in |
height, assigned to Seismic Design Category D, E or F
|2b. Foundations for other structures assigned to Seismic Design Category D, E or F||3,000 psi|
|3. Precast nonprestressed driven piles||4,000 psi|
|4. Socketed drilled shafts||4,000 psi|
|5. Micropiles||4,000 psi|
|6. Precast prestressed driven piles||5,000 psi|
For SI: 1 pound per square inch = 0.00689 MPa.
The concrete cover provided for prestressed and nonprestressed reinforcement in foundations shall be not less than the largest applicable value specified in Table 1808.8.2. Longitudinal bars spaced less than 11/2 inches (38 mm) clear distance apart shall be considered to be bundled bars for which the concrete cover provided shall be not less than that required by Section 126.96.36.199.4 of ACI 318. Concrete cover shall be measured from the concrete surface to the outermost surface of the steel to which the cover requirement applies. Where concrete is placed in a temporary or permanent casing or a mandrel, the inside face of the casing or mandrel shall be considered to be the concrete surface.
|FOUNDATION ELEMENT OR CONDITION||MINIMUM COVER|
|1. Shallow foundations||In accordance with Section 20.6 of ACI 318|
|2. Precast nonprestressed deep foundation elements|
|Exposed to seawater||3 inches|
Not manufactured under plant conditions
|Manufactured under plant control conditions||In accordance with Section 188.8.131.52.3 of ACI 318|
|3. Precast prestressed deep foundation elements|
|Exposed to seawater||2.5 inches|
|Other||In accordance with Section 184.108.40.206.3 of ACI 318|
|4. Cast-in-place deep foundation elements not enclosed by a steel pipe, tube or permanent casing||2.5 inches|
|5. Cast-in-place deep foundation elements enclosed by a steel pipe, tube or permanent casing||1 inch|
|6. Structural steel core within a steel pipe, tube or permanent casing||2 inches|
|7. Cast-in-place drilled shafts enclosed by a stable rock socket||1.5 inches|
For SI: 1 inch = 25.4 mm.