轻骨料施工预处理方法对高强轻骨料混凝土施工性能与长期强度的影响

Influences of lightweight aggregate construction pre-treatment methods on construction property and long-term strength of high-strength lightweight aggregate concrete

通过实验研究了轻骨料不预湿、浸水预湿、加压预湿、真空预湿等施工预处理方法对高强轻骨料混凝土施工性能与长期强度的影响。结果表明:较之目前国内常用的浸水预湿法,采用真空预湿法、加压预湿法可更为有效地提高高强轻骨料的预湿程度及所拌制混凝土的流动性,对混凝土施工有利,但应注意控制轻骨料在新拌混凝土中的上浮问题;采用加压预湿法会显著降低高强轻骨料混凝土的强度,采用真空预湿法、浸水预湿法对轻骨料混凝土后期强度的发展最为有利。

The influences of lightweight aggregate construction pre-treatment methods including no pre-wetting,soaking pre-wetting,pressure pre-wetting,vacuum pre-wetting,etc.on the construction property and long-term strength of high-strength lightweight aggregate concrete are studied.The result indicates that comparing with soaking pre-wetting method which is widely used in our country,the methods of vacuum pre-wetting and pressure pre-wetting can better improve the pre-wetting degree of high-strength lightweight aggregate and the fluidity of fresh concrete,which benefits the concrete construction;but the up-floating of lightweight aggregate in fresh concrete should be well controlled.It also indicates that the strength of high-strength lightweight aggregate concrete is reduced obviously by using pressure pre-wetting method;It is most beneficial to the improvement of post-strength of lightweight aggregate concrete to use the soaking pre-wetting method or vacuum pre-wetting method.