Source: American Concrete Institute, Farmington Hills, Mich.
The just-published ACI 318-11, “Building Code Requirements for Structural Concrete and Commentary” reflects extensive changes from the 2008 edition, including these key items:
- Nominal strengths are defined for adhesive anchors in cracked and uncracked concrete, plus those subject to sustained loads. The Code provides criteria for overhead installation of adhesive anchors and requires installer certification in certain instances. Seismic requirements for anchoring to concrete have also been revised.
- Enhanced reinforcement detailing for seismic applications. New requirements include reinforcement detailing for distinct segments of special structural wall systems, detailing of horizontal bars at special boundary elements, and tightened confinement details for flexural hinge regions of large beams.
- Test methods ASTM D516 and D4130 are referenced to determine the concentration of dissolved sulfates in water, brackish water, or seawater, and ASTM C1580 is referenced to determine percent sulfate by mass in soil.
- Newly available deformed bar types are integrated into appropriate provisions. Grade 80 deformed bars conforming to ASTM A615 or A706 are allowed for non-seismic applications. Zinc and epoxy dual-coated reinforcing bars per ASTM A1055 are also now recognized.
- Test records for determining standard deviation for a mixture design can now be up to 24 months old. Testing agencies performing acceptance testing of concrete are required to comply with ASTM C1077.
- Detailing requirements of temperature and shrinkage reinforcement for post-tensioned slabs have been revised.
All ACI publications, including 318-11 ($192.50; ACI members, $116.00) can be ordered from the Institute bookstore, 248/848-3800 or at www.concrete.org.