The American Concrete Institute (ACI) has released a major update to its structural concrete code, now known as ACI 318-25. This is the first significant revision since ACI 318-19 was released in 2019. The updated code introduces new guidance on sustainability, deep foundations, shear friction, and performance-based wind design (PBWD).
Table of Contents
Overview of ACI 318-25
ACI 318 is the most widely used standard for the design and construction of structural concrete buildings and non-building structures. It applies to all major types of concrete systems including:
- Cast-in-place concrete
- Precast concrete
- Prestressed and non-prestressed concrete
- Shotcrete and composite systems
The ACI 318-25 version was officially released in print on July 9, 2025, and is also available in a digital format as ACI 318-25 PLUS, which will receive continuous updates.
Key Updates in ACI 318-25
1. New Sustainability Guide
- Introduces a separate sustainability appendix.
- Provides templates and frameworks to help meet local sustainability regulations (e.g., Global Warming Potential targets).
- Focuses on low-carbon concrete options, but does not enforce specific limits—local jurisdictions still set the rules.
- Includes guidance for designing structures with resiliency to natural disasters like tsunamis and tornados.
This guide does not add binding rules but helps designers achieve carbon neutrality and environmental goals.
2. Performance-Based Wind Design (PBWD)
- Offers a new advisory guide for using PBWD in tall or supertall buildings.
- It is not part of the main code, but can be used when clients or local codes require it.
- Based on wind tunnel testing or advanced simulations to improve safety and efficiency in high-rise buildings.
This section helps engineers develop safe wind-resistant designs for taller structures.
3. Deep Foundations – More Detailed Provisions
- Builds on the initial inclusion of deep foundations in ACI 318-19.
- Now consolidates deep foundation requirements from International Building Code (IBC) into a clearer format.
- Offers improved clarity for designers working on pile foundations and other deep systems.
4. Updated Seismic Design Provisions
- Responds to design queries from high seismic areas like California, Oregon, and Washington.
- Clarifies and improves guidance from the 318-19 version.
- Helps engineers design more efficient and code-compliant structures in seismic zones.
5. Shear Friction Section Clarifications
- Resolves confusion caused by 318-19 updates.
- Specifically addresses issues related to shear friction in basement walls and retaining structures.
- Prevents overly broad application of incorrect formulas, ensuring better design accuracy.
Why These Changes Matter
These updates reflect the changing needs of the construction industry, especially in terms of:
- Environmental sustainability
- Seismic resilience
- Modern wind loading practices
- Efficient and clear foundation design
ACI has made it clear that local jurisdictions still have the final say in enforcing many of these provisions, especially those related to sustainability and PBWD.
Summary Table: ACI 318-25 Updates
| Area of Update | Description |
|---|---|
| Sustainability Guide | Framework for meeting local low-carbon & GWP targets |
| PBWD Guide | Advisory for tall buildings exposed to high wind loads |
| Seismic Design | Clarified provisions for high-risk seismic regions |
| Deep Foundations | Consolidated and improved foundation design guidance |
| Shear Friction | Fixed design inconsistencies in basement and retaining structures |
Source: https://www.concrete.org/newsandevents/news/newsdetail.aspx?f=51749030
Also Read:
- IS 456 : 2025 Preliminary Draft Version – Download PDF
- IS 800 – 2025 Draft Version – Download Pdf
- IS 1893 : 2023 Draft Version – Download PDF
I am a Professional Civil & Structural Engineer having more than 4 years of experience in Engineering, Procurement and Construction industry. Here i sharing the latest updates of EPC Projects and Construction News.