@proceedings {28911,
	title = {End-region cracking in pretensioned concrete girders employing 0.7-in. strands: Time-dependent and service-load effects},
	journal = {Proc., PCI 2018 Convention and National Bridge Conf. Chicago: PCI},
	year = {2018},
	abstract = {The use of 0.7-in. diameter strands instead of 0.5-or 0.6-in. diameter strands in pretensioned girders results in greater end-region stresses that can lead to cracking. End-region cracks, which might negatively affect the durability and strength of girders, develop at prestress transfer and change in length, width, and number over time and under applied loads. This paper investigates the effects of applied loads and timedependent volumetric changes of concrete on cracking conditions within the endregions of Texas bulb-Tee girders (Tx-girders) that employ 0.7-in. diameter strands on a 2-by 2-in. grid. A series of full-scale specimens was fabricated at Ferguson Structural Engineering Laboratory and was subjected to shear-critical loading at an age of 28 days or greater. The specimens were well-instrumented to estimate the endregion stresses at the time of prestress transfer. Crack widths and patterns, as well as prestress losses, were also monitored throughout the life of the specimens, including the duration of the shear tests. The number and width of cracks increased noticeably within the first three weeks after prestress transfer. However, the widths of most web cracks were reduced nearly by half under relatively small applied loads. The results provide valuable insight into acceptance limits for end-region cracks to ensure serviceable and durable pretensioned girders.},
	url = {https://www.pci.org/PCI_Docs/Papers/2018/37_Final_Paper.pdf},
	author = {H Kim and Rodolfo Bonetti and Alistair Longshaw and Hossein Yousefpour and Trevor Hrynyk and O Bayrak}
}
