蒸发抑制剂对白鹤滩大坝混凝土层间性能影响北大核心CSCD

研究水分蒸发抑制剂在不同环境条件下对低热水泥混凝土层间性能的影响,对控制大坝施工质量具有重要意义。本文通过开展复杂环境下水分蒸发抑制剂对混凝土贯入阻力、表层含水量及劈裂抗拉强度影响的试验研究,探究了水分蒸发抑制剂对混凝土层间性能的影响规律及机理。研究结果表明:低风速时,水分蒸发抑制剂可以有效减缓混凝土表层含水量的下降,降低贯入阻力;而当风速较高时,由于抑制剂溶液无法稳定成膜导致其对混凝土表层水分蒸发的抑制效果变差。此外,喷洒水分蒸发抑制剂可以在一定程度上提高低风速时混凝土的层间劈裂抗拉强度,但在高风速作用下会产生不利影响,这可能与高风速下抑制剂溶液无法稳定成膜且会导致下层混凝土表层产生浮浆等原因有关。本文定量化分析了水分蒸发抑制剂对混凝土层间性能的影响,为实现混凝土层间性能控制提供参考依据。

Influence of evaporation retardants on concrete interlayer performance of Baihetan dam

For dam construction quality control, it is of great significance to study the effect of water evaporation retardants on the interlayer performance of low-heat cement concrete under different environmental conditions. This paper examines the influence and mechanism of water evaporation retardants on concrete interlayer performance through experimental tests on the influence of water evaporation inhibitor on concrete penetration resistance, surface water content, and splitting tensile strength in the condition of complicated environment. The results show that at low wind speeds, water evaporation retardants can effectively slow down the decrease in water content in the concrete surface layer, and reduce penetration resistance; while at high wind speeds, retardant solution cannot stabilize its film formation, resulting in a poorer inhibitory effect on water evaporation from the concrete surface. At low wind speeds, water evaporation retardants spraying can also be used to improve the interlaminar splitting tensile strength of concrete to a certain extent, but it poses an adverse effect under high wind speeds, which may be related to the inability of retardant solution to form a stable film and the formation of laitance on the surface of the lower concrete layer. This paper presents a quantitative analysis on the effect of water evaporation retardants on the interlayer performance of concrete, thus helping improve its performance control.