Alberto T. Ramirez Garcia, Ph.D., P.E., Project Manager at Tatum-Smith Engineers, Rogers, AR, USA; Researcher at the Department of Civil Engineering, National University "Santiago Antúnez de Mayolo," Huaraz, Perú.

Biography: Alberto T. Ramirez Garcia, Ph.D., P.E. is a Project Manager at Tatum-Smith Engineers, Rogers, AR, USA., and he is a researcher at the Department of Civil Engineering, National University “Santiago Antúnez de Mayolo,” Huaraz, Perú.

Dr. Alberto Ramirez Garcia is from Huaraz, Perú and received his Bachelor Studies in civil engineering from the National University “Santisago Antúnez de Mayolo,” Huaraz, Perú, in 2001. He earned his Master and PhD from the University of Arkansas, Fayetteville, Arkansas, USA in 2012 (under the Fulbright scholarship) and 2016 (as a research assistant) respectively. He completed his post-doctoral research at Tatum-Smith Engineers and University of Arkansas. He is a Fulbright fellowship and a member in Golden Key International Honor Society. He is a Professional Engineer in USA and Perú. He serves as a reviewer in different international journals and has published several research papers. His research interests include prestressed concrete, mixture proportioning, concrete materials, finite element analysis and numerical analysis of the bond behavior of prestressing strand, performance seismic design, computer simulation of structures under dynamic loads, structural steel design, tornado shelter design under FEMA parameters.

Speech Title: Effect of concrete compressive strength on transfer length

Abstract: This paper examines the effect of concrete compressive strength on the transfer length of prestressing strands. The paper includes the results from several research projects conducted at the University of Arkansas (UA) and from testing reported in the literature. At the UA, 57 prestressed, precast beams have been cast since 2005. The beams were cast with selfconsolidating concrete (SCC), high strength concrete (HSC), lightweight self-consolidating concrete (LWSCC), and ultra-high performance concrete (UHPC). Using data from the UA and from the literature, an equation to estimate transfer length was developed and presented. The results were also compared with the American Concrete Institute (ACI 318) and the American Association of State Highway and Transportation Officials (AASHTO) prediction equations for transfer length, which were designed for conventional concrete. The results also showed that there was little change in transfer length when the compressive strength at release was greater than 34.5 MPa.

Keywords: Pretensioned concrete, Transfer length, Bond

Acknowledgements: Financial support from the Mack-Blackwell Rural Transportation Center (MBTC) Grant Award Number DTRT07-G-0021 at the University of Arkansas is gratefully acknowledged. The authors would like to thank Insteel Industries Inc. for providing the strand for this research.