Laboratory Facilities: Projects

Technical Report REMR-CS-57:

Performance Criteria for Concrete Repair Materials
Phase II Laboratory Results

WDP was retained by the United States Army Corps of Engineers to generate an overall investigation to develop performance criteria for cement-based repair materials. In Phase I of the study, preliminary criteria for dimensionally compatible repair materials were developed based on a review of the literature. This review concentrated on identifying pertinent material properties, appropriate test methods, and demonstrated field performance.

WDP performed laboratory and field tests to evaluate the preliminary performance criteria which were conducted in Phase II of the project. These tests included unrestrained and restrained drying shrinkage, modulus of elasticity, tensile and compressive creep, coefficient of thermal expansion, and flexural, compressive, and direct tensile strengths.

Concurrent field tests were also conducted to evaluate material durability. Results of the laboratory and field performance tests were correlated to provide a basis for development of durability performance criteria for cement-based materials. Twelve candidate repair materials were selected for the experimental portion of the project. Each material was subjected to a series of standard and nonstandard laboratory tests to determine properties which were perceived to be of interest in a repair context and provide some basic information about their behavior.

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Veterans Affairs Medical Center

Detroit, Michigan

WDP was retained to provide assistance in analyzing a claim regarding the ceramic glazed brick for the exterior brick cladding of the new Veterans Affairs Medical Center in Detroit, Michigan. The particular types of brick specified for this project were multi-colored glazed molded brick. Most of the brick related claims centered on the difficulties the brick manufacturer had in producing brick that met the Project Specifications as well as color and appearance requirements. WDP was asked to review the project documents and to provide the Department of Veterans Affairs an assessment of the claims and related issues for the production of the brick, physical requirements, and testing procedures of the Project Specifications.

WDP conducted extensive testing in our in-house laboratory to compare the results of brick tested using various freezing and thawing methods. Based on our testing and project design analyses, WDP was able to help our client resolve the dispute favorably.

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Beckett Meadows

West Chester, Ohio

Beckett Meadows is a 19 multi-family building condominium development consisting of 5 multistory and 14 single story residential buildings. Shortly after construction in the late 1990’s, residents complained the asphalt shingles were blowing off the roofs of the buildings. The shingles were dimensional (architectural) shingles applied over an oriented strand board roof deck.

WDP was contracted to determine the cause of the shingle blow-off phenomenon and develop a scope of work to prevent additional shingles from blowing from the roofs. To determine the cause of shingle blow-offs and develop suitable repairs, WDP performed a series of site investigations to document the as-built condition of the roof and perform in-situ testing. Shingle specimens were extracted from the roofs and transported to WDP’s laboratory for additional testing and experimentation.

The findings of WDP’s investigation indicated that the front edges of the shingles were not adequately sealed to the underlying course of shingles. Inappropriate fastening and a defect in the shingle manufacturing permitted uplifted shingle tabs to pull through the roof nails during high wind events and blow from the roofs.

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Virginia Tech - Campus-wide Efflorescence Investigation

Blacksburg, Virginia

WDP was retained to investigate the causes of chronic calcium carbonate efflorescence problems in the “Hokie Stone” masonry walls of the campus buildings.  WDP investigated the facades of new buildings with the unsightly stains and contrasted them with the construction of older facilities without problems to identify materials and details responsible for the phenomenon.  Materials testing on stone and mortar constituents were sampled from active projects and tested in the laboratory to identify potential sources of the calcium salts and the properties of the façade materials.  Water penetration rates through the facades were compared to results of laboratory mock-ups constructed with alternative construction methods to determine if the resistance to wind-driven rain could be improved.  The mock-ups also provided valuable data regarding the constructability of the recommended improvements.

WDP provided the University with recommendations on how to reduce or eliminate the efflorescence problems in the facades along with methods to clean existing facades and make improvements to reduce the potential for recurrence of the problems.  Deliverables included guide specifications and details for construction, an inspector checklist, and formats for pre-construction meetings.

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