Determination of dam concrete strength parameters considering the effects of ambient environment, member size and aggregate size: A case study of Baihetan Dam

The inconsistency in strength parameters between full-graded dam concrete and wet-sieved concrete is primarily attributed to variations in curing conditions, member size, and aggregate size. To ensure more reliable strength parameters for the structural analysis of the Baihetan Dam, comprehensive strength tests were conducted on site-casting full-graded and wet-sieved concrete. Full-graded concrete specimens and a portion of wet-sieved concrete specimens underwent natural curing on site or in close proximity to the laboratory, while the remaining wet-sieved concrete specimens were cured in seven large environmental chambers with controlled temperatures and relative humidity. The quantitative effects of curing conditions, specimen size and maximum aggregate size on the compressive and splitting tensile strength of dam concrete were obtained through strength tests. Subsequently, based on the test results, by introducing the equivalent age-adjusted coefficient Cea, the member size-adjusted coefficient Cms and the aggregate size-adjusted coefficient Cas, a strength determination method for full-graded concrete that can consider the above three factors was proposed and validated. Finally, according to the measured temperature and relative humidity history of the dam concrete and ambient environment, the real strength parameters of the full-graded concrete of Baihetan dam were determined by the proposed method. The validation and practical application of the proposed method indicate that this method can meet the actual use requirements of the Baihetan dam project, and can provide more reliable full-graded concrete strength parameters for dam structure analysis than traditional methods. •Curing conditions, specimen size and aggregate size effects on dam concrete strength should be considered.•The equivalent age, member size and aggregate size adjusted coefficients are derived.•A strength determination method for dam concrete is proposed and validated.•The strength determination method meets Baihetan dam's application requirements.