高韧性水泥基复合材料强度尺寸效应试验研究与正交分析-中国材料进展

文章信息/Info

Title:: Experimental Study and Orthogonal Analysis of Strength Size Effect of High Toughness Cementitious Composite

Author(s):: LI Xue-yang1; J IANG Shi-yong2; FEI Wei1; YAO Wei-lai1; (1.Department of Military Civil Engineering; 2.Department of Training; Logistical Engineering University, Chongqing 401311, China)

Keywords:: size effect; high toughness cementitious composite; mixture ratio; compressive test; orthogonal analysis

摘要:: 尺寸效应是水泥基材料的固有特性，它与材料的配合比、强度以及结构组成等因素有关。高韧性水泥基复合材料是一种新型复合材料，具有优异的韧性，但同时其结构组成与普通混凝土相比也具有较大差异。然而，目前针对尺寸效应的研究大多限于普通混凝土和高强混凝土，并且尚无相关标准对高韧性水泥基复合材料尺寸效应的处理作出规范。为了探究该种复合材料的抗压强度尺寸效应，本文采用两种不同尺寸的立方体试件，对16组不同配合比的高韧性水泥基复合材料进行了单轴抗压试验和正交分析，研究了纤维掺量、水胶比、粉煤灰掺量和砂胶比这四个因素对材料强度尺寸效应的影响情况。试验结果表明：与普通混凝土相比，高韧性水泥基复合材料的脆性特征明显减小；诸因素对尺寸效应影响的主次顺序为水胶比＞纤维掺量＞粉煤灰掺量＞砂胶比，其中水胶比和纤维掺量的影响均非常显著，而砂胶比对尺寸效应影响甚微。

Abstract:: Size effect is the inherent characteristic of cementitious materials, which is related to the factors such as mixture ratio, strength and structure composition. The High toughness cementitious composite is a new type of composite material with excellent toughness, but at the same time the structure of it is quite different from that of ordinary concrete. However, most of the current studies on size effects are limited to ordinary concrete and high-strength concrete, and there is no relevant standard to regulate the size effect of high toughness cementitious composite. In order to explore the compressive strength size effect of high toughness cementitious composite, the uniaxial compressive tests and orthogonal analysis on 16 groups of high toughness cementitious composites with different ratios and two sizes of cube specimens were carried out to study the influence of four factors including fiber content, water-binder ratio, fly ash content and sand-binder ratio on the compressive strength size effect of this material. The test results show that the brittleness of high toughness cementitious composite is obviously reduced compared with ordinary concrete. The primary and secondary order of the influence of this four factors on size effect is water-binder ratio > fiber content > fly ash content > sand-binder ratio; the influence of water-binder ratio and fiber content is highly significant, while sand-binder ratio has little effect on the size effect