改性剂对橡胶水泥砂浆强度的影响

Effects of surface modification on the strength of rubber cement mortar

试验研究了水洗、NaCl、CaCl2、KH560、KH570、CCl4六种改性方式对橡胶水泥砂浆抗压强度和劈拉强度的影响变化规律,其中水洗改性方式使橡胶水泥砂浆的抗压强度和劈拉强度分别提高了7.6%和9.9%;无机改性剂中,NaCl和CaCl2对橡胶水泥砂浆强度的提高均是负面作用,5%浓度的NaCl溶液改性作用与水洗相当,使橡胶水泥砂浆的抗压强度提高了8.6%,有机改性剂中KH560和KH570的效果优于CCl4,与基准橡胶水泥砂浆相比,KH560和KH570改性后的橡胶水泥砂浆的抗压强度分别提高了5%和4.7%。分析表明,无机改性剂对橡胶水泥砂浆强度的影响机理复杂,NaCl会在混凝土内部形成晶体压力,CaCl2对水泥的水化反应有影响;而有机改性剂KH560和KH570可以改善橡胶颗粒与水泥石的粘结界面。

The effects of six surface modification methods on the compressive strength and split strength of rubber cement mortar were investigated.The six methods include water washing,sodium chloride solution,calcium chlorides solution,KH560 solution,KH570solution,and CCl4 solution.The method of water washing enhanced the compressive strength by 7.6% and compressive strength by 9.9% of rubber cement mortar.Sodium chloride solution and calcium chlorides solution had negative effects on the strength of rubber cement mortar.Sodium chloride solution of 5% concentration enhanced the compressive strength of rubber cement mortar by 8.6%,which was similar to water washing.The effects of KH560 and KH570were better than that of CCl4 in the organic modifiers,and the compressive strength of rubber cement mortar was increased by 5% and 4.7% using the KH560 and KH570solutions respectively compared with that of the unmodified rubber cement mortar.The results suggested that the impact mechanism of inorganic modifiers on the strength of rubber cement mortar is complex.Crystal pressure can be formed in the concrete caused by NaCl and the hydration reaction caused by CaCl2 can be harmful to the cement.The organic modifiers,such as KH560 and KH570,can ameliorate the interface between the rubber and cement paste.