Leo W. Zegler

Senior Specialist


Leo Zegler has extensive experience testing and evaluating various construction materials, including but not limited to concrete, aggregates, stone, mortar, masonry, stucco, clay tile, and grout. Most of his experience is in concrete and aggregate testing, which includes tests such as concrete drying shrinkage, concrete compressive strength, concrete flexural strength, concrete freeze/thaw testing, concrete splitting tensile strength, concrete modulus of elasticity, plastic concrete testing, aggregate gradations, aggregate absorptions and specific gravity, and aggregate sample preparations. Mr. Zegler is also responsible for testing concrete and aggregate proficiency sample testing for the Cement and Concrete Reference Laboratory and the AASHTO.

Mr. Zegler is experienced in mortar masonry, historic masonry durability testing, and evaluation, and chloride permeability testing. He helps perform equipment calibrations and verifications to maintain laboratory accreditation.


Laboratory Testing

  • Ford Island Bridge - HI: Alkali-silica reactivity testing
  • Trial batching and concrete testing for self-consolidating concrete; admixture development
  • Wacker Drive Bridge Reconstruction - Chicago, IL: Concrete testing of high-performance concrete


Field Testing

  • Brookfield Zoo - Brookfield, IL: Condition assessment of pool
  • Shedd Aquarium - Chicago, IL: Condition assessment of pool
Professional Affiliations

American Concrete Institute


ACI Certified Aggregate Testing Technician - Level I
ACI Certified Concrete Laboratory Testing Technician - Level I
ACI Certified Concrete Strength Testing Technician


William Rainey Harper College
Associate of Arts, 1997