Concrete Repairs Recognized

Edited by Paul Fournier | September 28, 2010

Two New England projects have won awards from the International Concrete Repair Institute (ICRI) at the organization's 2006 Fall Convention in Denver, Colorado. The historic restoration of the eight- to 10-story 330 Stuart Street masonry building in Boston and the strengthening of 1230 Washington Street Parking Garage in Newton, Mass., received Awards of Merit from ICRI, a nonprofit association with more than 1,800 members worldwide.

The Mayorhold MSCP, Northampton, United Kingdom, was chosen as the ICRI 2006 Project of the Year, while seven 2006 Awards of Excellence and 10 Awards of Merit were presented at the annual conference of the international group, which serves as an information and education resource on repair, restoration and protection of concrete and other structures.

Submitted by Gale Associates, Inc., the project engineer/designer, 330 Stuart Street won an award in the Historic Restoration category.

Originally designed by Densmore, LeClear & Robbins of Boston, 330 Stuart Street was built in two phases — the first phase in 1917 and the second in 1928. The eight- to 10-story building, originally owned and occupied by the Salada Tea Company, is a historically significant transitional masonry building. Transitional masonry buildings were constructed during the late 19th and early 20th centuries. These buildings use multi-withes masonry walls, and have concrete elements along with structural steel framing.

The owner, Liberty Mutual Group, retained building envelope consultant Gale Associates, Inc., and repair contractor Phoenix Bay State Construction of Boston, to perform an in-depth façade inspection to determine the cause and origin of visible cracks, spalls and water infiltration. The team produced detailed plans and specifications and performed repairs using the latest methods and materials supplied by Sika Corporation of Scituate, R.I., and Heckmann Building Products Inc. of Boston, which are expected to extend service life more than 50 years.

In the Strengthening Category, Merit Award winner 1230 Washington Street Parking Garage was submitted by consultant Simpson Gumpertz & Heger Inc. of Newton, Mass.

In the last several years, fiber-reinforced polymer (FRP) composite systems emerged as a powerful tool in concrete strengthening applications. Large-scale use of these systems, particularly near-surface-mounted (NSM) carbon FRP (CFRP) bars, however, remains relatively uncommon. The strengthening work at the 1230 Washington Street Garage, owned by Newton Investors Ltd., Partnership of Yardley, Pa., is said to be a clear-cut example of innovative thinking, technological savvy, and expertise in materials and engineering techniques.

The garage exhibited numerous signs of distress, such as excessive deflections of the decks at bay midspans and extensive concrete deterioration, cracking and spalling.

Project engineer/designer Simpson Gumpertz & Heger Inc. began the project with a condition survey of the garage, structural analysis of the decks, load tests of decks with and without prototype strengthening repairs, and design of the strengthening system with NSM CFRP bars.

To review the performance of CFRP systems, the evaluation of the structure included a load-testing program of garage decks with and without the NSM system in place. The goal of the testing program was to define a satisfactory safety factor against collapse in case CFRP is lost due to exposure to fire and to demonstrate superior performance of a strengthened structure while ensuring that any solution would meet the client's budget and maintenance expectations. Repair contractor CCI of North Hampton, N.H., performed the work using materials provided by Hughes Brothers, Inc. of Seward, Neb., and DeNeef Construction Chemicals (U.S.), Inc. of Houston, Texas.

This project featured comprehensive concrete repairs and introduced a high-performance CFRP strengthening system, featuring 14,000 linear feet of CFRP bars that resulted in a durable structural solution and an extended life expectancy of the garage.