Events

Civil and Environmental Engineering PhD Dissertation Defense: Anas Yosefani
Wednesday, May 16, 2018 - 1:00pm

The Department of Civil and Environmental Engineering is pleased to announce Anas Yosefani's PhD Dissertation Defense: "Flexural Strength, Ductility, and Serviceability of Beams that Contain High-Strength Steel Reinforcement and High-Grade Concrete."

Date: Wednesday, May 16, 2018
Time: 1:00pm
Location: Engineering Building 502J (Dean's Conference Room)
Adviser: Dr. Franz Rad

Utilizing the higher capacity steel in design can provide additional advantages to the concrete construction industry
including a more efficient use of high-strength concrete (HSC), reduction of congestion, improved concrete placement,
reduction in the required reinforcement and cross sections which would lead to savings in materials, shipping, and
placement costs. Using high-strength reinforcement (HSR) is expected to impact the design provisions of ACI 318 code
and other related codes.

The current research aims to provide a closer investigation of the flexural behavior of beams reinforced with HSR
(including A615 Grade 100 and A1035 Grades 100 and 120) and HSC up to 12000 psi. The research includes analytical
studies and conforming experimental tests, and it is directed to provide a number of recommendations and design
guidelines including: strain limits (tension-controlled and compression-controlled, and minimum strain in steel);
possible change for strength reduction factor equation for transition zone (Φ); recommendation regarding the minimum
amount of reinforcing steel (ρmin) for HSR; and recommendations regarding the prediction of deflection and crack width
at service load levels. Moreover, this research includes long-term deflection test for a beam made with high grade
concrete and high-strength steel under sustained load for twelve months to evaluate the creep deflection and examine
the applicability of the current ACI 318 time-dependent factor, λ, which does not consider the yield strength of
reinforcement and the concrete grade.