乌东德大坝低热水泥全级配混凝土强度性能试验研究

为正确评价乌东德大坝低热水泥混凝土的强度性能,在施工现场分春夏秋冬4次浇筑成型低热水泥全级配和湿筛混凝土试件,开展不同龄期混凝土抗压强度、劈拉强度、轴压强度和弹性模量试验研究。根据试验结果,对低热水泥混凝土强度性能的时变特性及全级配和湿筛混凝土强度性能的换算关系展开分析。结果表明,不同季节低热水泥混凝土的抗压和劈拉强度均达到设计强度;365d龄期混凝土强度性能相较于设计龄期仍有明显增长;低热水泥全级配和湿筛混凝土抗压和劈拉强度的换算关系均服从正态分布,具有95%保证率的换算关系分别为0.68和0.62。实际大坝工程,建议根据分析需要选用平均值或95%保证率的比值作为换算关系。

Experimental study on strength properties of low heat cement fully-graded concrete of Wudongde Dam

To correctly evaluate the strength properties of low-heat cement concrete of Wudongde dam，the specimens of fully-graded and wet-sieved concrete are casted at the construction site for four times，the tests of compressive strength，splitting tensile strength，axial compressive strength and elastic modulus are performed． According to the test results，an analysis is made on the evolution of the strength properties of low heat cement concrete and the conversion relationship between the strength properties of the fully-graded and wet-sieved concrete． The results show that the compressive strength and splitting tensile strength in different seasons have all reached the design strength． The strength properties of concrete at 365 days is still significantly increased compared with the design age． The conversion relationship between the strength properties of the fully-graded and wet-sieved concrete all follows normal distribution，and the ratios of the compressive and splitting tensile strength of the fully-graded and wetsieved concrete with 95% guarantee rate are 0. 68 and 0. 62，respectively． In actual dam projects，it is recommended to select the average value or the ratio with 95% guarantee rate as the conversion relationship．