Materials, material properties and the interaction between materials are key to understanding how construction materials are intended to work, how they are performing in the field, and where they fail.
As is our general practice, we assemble a multi-disciplinary team with the necessary skills and information to evaluate materials and their interaction. This typically involves construction specialists, material scientists, laboratories, and others with specialized knowledge of the materials involved and their application. An investigation typically starts with field evaluation of a material by construction specialists and material scientists. This may include field testing, such as adhesion or strength testing, and collection of samples both of the material in question and other materials with which it is interacting. For example, paint may be tested in the field for adhesion to its substrate, and samples of paint together with its substrate are collected to allow the paint-to-substrate interface to be studied with a microscope. From there, sub-samples of the paint and substrate may be sent to an outside laboratory for chemical or other testing. As the formulation of many materials, such as coatings, membranes, sealants and plastics are proprietary, we frequently involve a product manufacturer’s laboratory and technical services as part of the team.
Understanding the materials and material interactions allows the fundamental forces at play in a failure to be determined. Perhaps a material has become brittle and shrunk due to cross linking of polymers, or has failed to wet, and hence bond to a substrate, or galvanic corrosion has been initiated. These sorts of interactions, which result from the fundamental properties of the materials and their interactions, occur at a microscopic level where they cannot be discerned by the naked eye, and are the root cause of many failures.
Once a material’s composition and interaction with other materials has been identified, the failure mode can be determined, and corrective action identified. We have applied this approach, looking at the fundamental properties of the materials involved, to find solutions to problems with a wide variety of materials and systems including: thermal insulation, sprayed-on fireproofing, adhesives, coatings, encapsulants, drywall, joint compound, plaster, masonry products, steel and copper corrosion, and electrical connections, just to name a few.
In explaining our findings to technical laypersons, we have found it useful to develop illustrations, including animations, and provide microphotography and macrophotography to better explain the way a material works, and relates to other materials, and the physical processes associated with a material failure.
Some assignments that included materials analysis include:
- Yale Plaster
- World Trade Center Column Fireproofing Failure
- Desert Ridge Stucco
- Iowa Historic Plaster
- Lowes Distribution Center Paint Failure
- New Haven Macey’s Bonding Adhesive
- Mooreland Federal Building Bonding Adhesive
Here are some examples of past projects that illustrate our approach.