John RollerPrincipal Structural Engineer, Structural Engineering & Mechanics
Mr. Roller has been involved in structural research and development programs; structural failure investigations; evaluation of damaged or distressed structures; field and laboratory structural load testing programs; material testing and evaluation programs; development and implementation of quality assurance programs; and structural instrumentation and monitoring programs. Mr. Roller has developed expertise in the areas of structural testing, structural evaluation, high-strength/high-performance concrete, fiber reinforced concrete, reinforced and prestressed concrete pipe and design and fabrication of precast/prestressed concrete components (including quality assurance inspection).
At CTLGroup, Mr. Roller has been involved in research and development activities related to the structural integrity of reinforced and prestressed concrete secondary containments for nuclear power generating facilities; utilization of fibrous materials as concrete reinforcement and structural applications of high-strength concrete. Specific areas of high-strength concrete research included basic material properties, bond development, shear strength, prestress losses, fatigue endurance and implementation in highway bridge structures.