养护条件对桥面用聚合物改性水泥砂浆力学性能的影响

Effect of Curing Condition on the Mechanical Property of the Polymer Modified Cement Mortar Used for Repair of the Bridge Surface

研究了羧基丁苯乳液SD 6 2 2S对桥面用水泥砂浆力学性能的改性效果。SD 6 2 2S乳液对提高水泥砂浆的抗折强度和粘结强度有显著作用 ,并可大幅度降低压折比、提高折弹比 ,养护条件对此有重要影响。根据本试验的原材料 试验条件和结果 ,按照德国交通部筑路局制定的桥面用聚合物改性水泥砂浆供货的技术条件 ,干湿混合养护方式比较合适。SD 6 2 2S的掺量因应用场合的不同而异。用于静荷载构筑物时 ,SD 6 2 2S掺量应≮ 10 % ;用于动荷载构筑物时 ,其掺量应≮ 15 %。

This paper is special in modifying effects of styrene-butadiene emulsion SD 622S on the mechanical properties of cement mortar used for the surface repair of the bridge based on the German standards and specifications.The polymer emulsion SD 622S effectively enhances both flexural strength and tensil bond strength,largely decreases the ratio of compressive strength to flexural strength and improves the ratio of flexural strength to elastic modulus.The curing methods have an great effect on the result,which shows that the combination of dry and wet curing methods is more appropriate,and the addition of polymer emulsion SD 622S is not the same as that at different sites.For structure under static load,the appropriate addition of polymer emulsion SD 622S must be more than 10 %,while for structure under dynamic load,it must be more than 15 %.