Papers by elias arturo ortiz morales
Mitigation and control of cracking is important for obtaining acceptable appearance and for long-... more Mitigation and control of cracking is important for obtaining acceptable appearance and for long-term durability of concrete bridge structures, especially those subjected to saltwater spray and deicing chemicals. In the current AASHTO LRFD Specifications and in the ACI 318 Code editions prior to 1999, flexural crack control requirements were based on the so-called Z-factor method developed by Gergely and Lutz in 1968. Their work was based on extensive statistical evaluation of laboratory experiments. ACI 318 decided in the 1999 edition to greatly simplify crack control requirements due increased evidence suggesting a reduced correlation between crack width and reinforcement corrosion. The ACI formula relates maximum bar spacing to steel stress under service loads and clear concrete cover. This paper presents the background of previous crack control methods and comparison of their impact on design of bridges and culverts. A new equation is proposed for adoption in the AASHTO LRFD Specifications that is intended to be simple, yet account for differences between bridge and building structures.
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Papers by elias arturo ortiz morales