Equivalent maturity for ambient temperature effect on fracture parameters of site-casting dam concrete

• A concept of equivalent maturity suitable for dam concrete was proposed.
• Different age of dam concrete specimens were poured on site in summer and winter.
• Variations of fracture parameters with ambient temperature and age were revealed.
• Relationship between fracture parameters with equivalent maturity were obtained.

This paper presents the influence of ambient temperature on the fracture properties of site-casting (or cast in-situ in other words) dam concrete. By virtue of the mixing tower system in the site of a super-high arch dam, the wedge splitting specimens with the maximum aggregate size of 150 mm were poured in summer and in winter seasons, respectively. The variations of fracture parameters obtained by experiment with different age were revealed, and the results show that the dam concretes poured in summer and in winter seasons show much difference in fracture characteristics at the age of 28 days, however, with the increase of age, the difference in fracture behavior decreased, and was almost zero at the age of 180 days. On top of that, by introducing the concept of equivalent maturity, the relationships between fracture parameters of site-casting dam concrete and equivalent maturity were obtained.