喷射混凝土早期力学特性及水化特征研究  

Research on early mechanical and hydration characteristics of sprayed concrete

作　　者：郭俊波 李钰轩 付佳 崔圣爱[2] 余雪平 夏葳 陈思宇[3] GUO Junbo;LI Yuxuan;FU Jia;CUI Sheng'ai;YU Xueping;XIA Wei;CHEN Siyu(China Anneng Group Third Engineering Bureau,Chengdu 610036,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 611756,China;School of Geophysics,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]中国安能集团第三工程局有限公司,四川成都610036 [2]西南交通大学土木工程学院,四川成都611756 [3]成都理工大学地球物理学院,四川成都610059

出　　处：《混凝土》2024年第7期84-88,共5页Concrete

基　　金：国家自然科学基金(52278277)。

摘　　要：目前采用的喷射混凝土黏结强度较低,在施工后的初始阶段无法满足支护强度的要求。因此通过引入硅灰、微珠、纤维素以及早强减缩剂探究不同复合胶凝材料的力学性能及水化热反应特性。基于Krstulovic-Dabic水化动力学模型开展复合胶凝材料水化过程研究,通过联合喷射混凝土早龄期抗压强度及劈裂强度分析其力学发展规律。结果表明:硅灰及早强减缩剂对混凝土早期力学强度均有显著提高作用,而纤维素及微珠对强度有降低作用;各工况下复合胶凝体系的水化动力学过程为结晶成核与晶体生长(NG)、相边界反应(I)和扩散(D)3个阶段;硅灰掺量的增加会增高溶解峰高度20.4%且提前反应峰出现时间22.2%;纤维素的掺加显著提高了溶解峰强度但降低了反应峰高度。The bonding strength of sprayed concrete currently used is relatively low,and it cannot meet the requirements for support strength in the initial stage after construction.Therefore,it explores the mechanical properties and hydration heat reaction characteristics of different composite cementitious materials by introducing silica fume,ceosphere,cellulose,and accelerator.Based on the Krstulovic-Dabic hydration kinetics model,the hydration process of composite cementitious materials was studied.The mechanical development law of the combined sprayed concrete was analyzed through the early age compressive strength and spliting strength.The results show that silica fume and accelerator have a significant effect on improving the early mechanical strength of concrete,while cellulose and ceosphere have a reducing effect on the strength.The hydration kinetics process of the composite cementitious system under various operating conditions consists of three stages,crystallization nucleation and crystal growth(NG),phase boundary reaction(I)and diffusion(D).The increase of silica fume content will increase the height of the dissolution peak by 20.4%and the occurrence time of the early reaction peak by 22.2%.The addition of cellulose significantly increased the dissolution peak intensity but reduced the reaction peak height.

关 键 词：力学性能 水泥水化 水化动力学 

分 类 号：TU528.53[建筑科学—建筑技术科学]