This is the Metric version of the latest ACI 318 code.
ACI 318-25 introduces several key changes compared to ACI 318-19, particularly in areas like seismic design, anchorage, and shear design. These updates aim to improve structural performance, enhance safety, and reflect advancements in concrete design practices.
Seismic Design:
Shear Design:
Other Notable Changes:
*
Damas
ACI 318-25 introduces several key changes compared to ACI 318-19, particularly in areas like seismic design, anchorage, and shear design. These updates aim to improve structural performance, enhance safety, and reflect advancements in concrete design practices.
Seismic Design:
- Reinforcement Grade Limits:
ACI 318-19 raised limits on the specified strength of reinforcement for earthquake-resistant shear wall and moment frame systems, allowing Grade 80 reinforcement in some seismic applications and disallowing Grade 40.
- Anchorage Provisions:
ACI 318-25 moves the strength reduction factors (ϕ) for anchorage to Chapter 21, aligning them with other chapters and introducing a new modification factor (ψa) to decouple Anchor Category adjustments and supplementary reinforcement conditions from ϕ. - Redundant Fastenings:
ACI 318-25 introduces a distinction between redundant and non-redundant fastenings, providing a capacity benefit for redundant fastenings.
Shear Design:
- One-way Shear:
ACI 318-25 includes updates to one-way shear provisions, with a lower bound of 1√f'c for all structures.
- Two-way Shear:
ACI 318-25 includes updates to two-way shear provisions, with a size effect factor of 1.0 for mat slabs and basement walls. - Shear Reinforcement:
ACI 318-19 revised the minimum shear reinforcement in non-prestressed beams.
Other Notable Changes:
- Load Combinations:
ACI 318-25 includes updates to load combinations, such as adding a 3000-year interval for wind loads and incorporating load combinations for tornadoes and tsunamis.
- Structural Integrity:
ACI 318-19 includes a new section (Section 7.7.7) incorporating provisions to ensure that failure of a portion of a slab does not lead to disproportionate collapse. - Deflection Calculations:
ACI 318-25 adds two more options for deflection calculations, applicable for one-way slabs without beams. - Concrete Cover:
ACI 318-19 specifies a minimum concrete cover of 3 inches (75 mm) for footings exposed to earth or weather. - Commentary:
Both ACI 318-19 and ACI 318-25 provide commentary for background information and further explanation of the code requirements.
*
Damas