Key Changes in the ACI 318-19 Concrete Code

An overview of recent changes to the ACI building code requirements for structural concrete

About this event

The American Concrete Institute (ACI) has recently completed the technical update to the Building Code Requirements for Structural Concrete and published the latest ACI 318-19.

The ACI 318 specifies the requirements for the safe design and construction of concrete structures. The code has been referenced by international building codes worldwide, such as the International Building Code (IBC), and it is expected that the ACI 318-19 will be adopted in the 2021 IBC.

As a structural designer working with concrete, keeping up with code updates can be time-consuming. But don’t worry; we’ve got you covered!

Join Eva Wu, ClearCalcs’ Structural Design Consultant, on Wednesday, March 22nd, 2023, from 1 pm to 2 pm Eastern Time (ET) to learn more about some major changes to the ACI 318-19 that might affect your concrete design and how you can ensure to meet the building code requirements with ClearCalcs concrete calculators.

In this webinar, we will cover:

• Overview of ACI and the Building Code Requirements for Structural Concrete
• Major changes in ACI 318-19 -- The new strength reduction factor -- The new calculation for shear capacity -- The new requirements for development length in high-strength reinforcements
• How the ACI 318-19 updates are reflected in ClearCalcs concrete calculators

Webinar Summary

The webinar discusses changes to the ACI 318-19 Concrete Code, which is the governing body for concrete design. The presenters cover general changes and specific topics such as reduction factor changes, minimum reinforcement requirements, shear capacity changes, and development length requirements. The ACI 318 is considered the "Bible" for structural concrete design.

The presenters highlight the higher strength reinforcement allowed in the new version of the ACI 318-19 Concrete Code, with a cap of 100k compared to the previous 85k. They also ask for feedback on how they can help designers efficiently design high strength reinforcement and discuss additional requirements for reinforcement, as well as changes to the design of steel concrete composite columns.

The current segment discusses changes to the development length requirements for reinforcement in the new ACI 318-19 Concrete Code, including a new factor called the reinforcement growth factor that considers the strength of the bar and increases the required length for engagement. Other changes include the renaming of the cover factor to the location factor and the simplification of the confining factor based on spacing and bar area.

The presenters also demonstrate how the new code affects through capacity and development, with a larger section required to accomplish the same capacity and a need for a longer development length. They conclude by announcing that Claire Calix now fully supports concrete design to ACI 318-19 and invite questions and feedback from the audience.

The presenters also mention that designing plain concrete for smaller footings is often a viable solution when it's hard to get the full development length on the rebar, and ClearCalcs now has a calculator that automatically checks if the footing passes as plain concrete if it doesn't pass due to insufficient development length. They also discuss potential reasons for changes to make bigger footings or design, including complexity and consolidation of equations, but admit they're not entirely sure and would love to hear from the audience about their experiences with the new shear provisions.