Title: Subzero Degree Fahrenheit Temperature Repairs of Concrete with Epoxy Mortar

Author(s): Floyd E. Dimmick, Sr.

Publication: Symposium Paper

Volume: 85

Issue:

Appears on pages(s): 239-258

Keywords: connections; curing; epoxy resins; joint fillers; low - temperature; mortars (material); precast concrete; quality control; repairs; viscosity; workability.

DOI: 10.14359/6544

Date: 4/1/1985

Abstract:
During the winter of 1980 the cooling tower portion of work on the Stoney Brook Energy Center, Ludlow, Massachusetts was stopped due to cementitious grout failure in the precast concrete joint connections. Each precast concrete tee was connected to another tee by a cementitious grout joint. The grout apparently foamed during the installation. It was reported by the contractor that the grout was installed under conditions of application favorable for proper usage as specified by the grout manufacture-The average compressive strenqth of the foamed portion of the grout was 400 psi (2 .8 MPa). The depth of the foamed grout varied from 2.5 to 4 inches (63-101 mm). Three very important factors influenced the selection of the replacement material : low substrate temperature during application, low temperature application ability and product curability at sub-zero degrees fahrenheit temperatures. After a thorough investigation by the contractor of epoxy and cementitious grout manufacturers, it became apparent only one company was capable of supplying a commercially available product able to meet the above stated application conditions. A patented two-component modified epoxy mortar was selected from a U.S. manufacturer. This report is broken down into eight categories: selection of repair material; epoxy mortar selection; surface preparation; equipment, mixing and installation; independent laboratory results; conclusions; and recommendations listing quality control measures to be followed by others attempting this type of repair.