大海子水库坝基防渗墙混凝土试验研究

Concrete test for dam base anti-seepage wall of Dahaizi Reservoir

结合大海子水库的要求,采用黏土配制塑性混凝土,讨论水灰比和黏土掺量对混凝土性能的影响。结果发现:黏土掺量越大,塑性混凝土的抗压强度、劈裂强度、弹性模量就越小;水灰比越大,塑性混凝土的抗压强度、劈裂强度、弹性模量就越小;相对而言,掺量的影响大于水灰比,但水灰比和黏土掺量对塑性混凝土抗渗性的影响不明显。推荐采用水灰比0.65、黏土掺量10%配合比方案,对施工后塑性混凝土的性能测试结果:抗压强度和抗渗等级均满足要求,且其抗渗等级高于设计等级4级,推荐配合比满足大海子水库坝基防渗要求。

Combined with the requirements of Dahaizi Reservoir project, tests were conducted to study the influence of water-cement ratio and clay content on the performance of concrete. The results of test demonstrate that higher clay content or water-cement ratio renders lower compressive strength, splitting strength and elastic modulus of plastic concrete; the influence of clay content is greater than that of water-cement ratio, but neither water-cement ratio nor clay content have obvious effect on seepage control performance of plastic concrete. The recommended mix proportion is water-cement ratio of 0.65 and clay content of 10%. The performance of concrete was tested after construction, showing the compressive strength and anti-seepage rating both meet the dam base cutoff requirements, with the anti-seepage rating higher than designed grade IV.