Events > Tilt-Up Convention and Expo 2023 - Tampa > SESSION

Applied Bond Breaker and Could Not Pour for a Week, Now What?

September 21, 2023 from 3:00pm to 3:30pm Eastern Standard Time

Tampa Convention Center [Lower Level - Ballroom D]

Sai Yerradoddi

Tilt-up construction is a building method that offers various advantages over traditional construction methods, including speed, efficiency, and durability. One of the techniques used in this method is casting the panels flat on a slab. However, before pouring the slab, a bond breaker must be applied to prevent adhesion between the newly placed panel concrete and the existing slab on grade. The bond breaker typically lasts for one to two weeks, and if panels are not poured within this timeframe, spraying the bond breaker over the rebar can be challenging and cause serious construction issues.

This seminar will explore the option of spraying the bond breaker over the panel rebar in place and examine how it affects the strength characteristics of the wall panel. We will collaborate with a concrete contractor and a university to conduct experiments on a complete panel poured and cured after applying the bond breaker over the panel rebar. We will present the experimental results and compare them to the strength characteristics of a traditionally formed panel (where the bond breaker was not applied over the panel rebar). This will provide valuable insights into scheduling and feasibility for concrete subcontractors in the field.

LEARNING OBJECTIVES

• Understand the importance of using a bond breaker in tilt-up construction to prevent adhesion between panel concrete and the existing slab on grade.
• Learn about the challenges associated with spraying the bond breaker over the rebar on a panel if the concrete is not poured within one to two weeks.
• Gain knowledge about the effects of applying a bond breaker over panel rebar on the strength characteristics of the wall panel in tilt-up construction.
• Advantages of applying bond breaker after the rebar placement of the panels.