针对胶凝砂砾石坝体材料和新型保护层材料抗渗和抗冻性能展开了试验研究,其中抗冻测试中引入气冻和冰冻两种测试手段以表征胶凝砂砾石抵抗冻融和温度循环的能力。结果表明,未掺加外加剂的胶凝砂砾石180d龄期抗渗可达到W8,90d龄期抗冰冻不足25次冻融循环,气冻350次温度循环后相对动弹性模量仍约65%,抗气冻可到600次以上温度循环。掺加外加剂的胶凝砂砾石相应龄期的抗渗为W12,抗冰冻达75次冻融循环,气冻350次温度循环后相对动弹性模量仍有80%以上。因此建议胶凝砂砾石中采用外加剂,并以长龄期180d为设计龄期。新型保护层材料的研发试验表明,变态胶凝砂砾石、富浆胶凝砂砾石均具有良好的防渗(抗渗等级W10以上)和抗冻能力(F300次冻融循环),可作为胶凝砂砾石坝上、下游防渗抗冻保护层材料。
A series of experiments were made to test the frostresistance (including frostresistance in air and frostresistance in water) and impermeability of CSG and a new type of protective materials. Results show that the impermeability level of CSG without additive cured for 180d can reach WS, and the CSG cure for 90d was destroyed in less than 25 freezingthawing cycles in water while was not destroyed in over 600 cycles in air. For the CSG with additive, the impermeability level at 180d can reach W12, and it was destroyed in over than 75 freezingthawing cycles in water while was not destroyed in over 350 cy cles in air. Therefore additive is recommended in CSG mixing design. Tests on a new type of protective ma terials show that CSG adding grout and CSG with more cementitious materials both have good impermeabili ty levels (over WIO) and frostresistance (F300) and can be used as protective layers in CSG dams.