短切碳纤维混凝土的基本力学性能与分析

Basic mechanical properties and analysis of chopped carbon fiber reinforced concrete

碳纤维是1种环保无害的新型有机材料,其不仅强度高,而且还具有耐超高温、耐疲劳、耐腐蚀等多种优越的力学性能。将短切碳纤维加入到混凝土中可有效提高混凝土的抗冲击性能、抗拉强度以及抗折强度,这种方法不仅可以降低混凝土干缩率,还可以改善其耐磨性能,提高混凝土的减震能力等。本课题为探究短切碳纤维对混凝土基本力学性能的影响机制,分析出短切碳纤维对混凝土的增强机理。以C35普通混凝土为研究对象,短切碳纤维长度和掺量为变量,通过坍落度试验与静态力学性能试验将碳纤维混凝土与素纤维混凝土的基本力学性能进行对比分析。试验结果表明:同纤维长度下,随碳纤维掺量的增加,混凝土的劈拉强度和抗折强度明显提高,劈拉强度最大增幅达110%,抗折强度最大增幅达36.9%。而抗压强度出现不同程度的降低。在光学显微镜下,碳纤维在混凝土基体材料中呈各向异性,呈现出良好的密闭空间网状结构。在混凝土破坏时,起到了良好的阻裂作用。

Carbon fiber is an environmentally friendly and harmless new organic material.It not only has high strength,but also has many excellent mechanical properties such as resistance to ultra-high temperature,fatigue and corrosion.The addition of chopped carbon fiber to concrete can effectively improve the impact resistance,tensile strength and flexural strength of concrete.This method can not only reduce the shrinkage rate of concrete,but also improve its wear resistance and improve the shock absorption capacity of concrete.In order to explore the influence mechanism of short-cut carbon fiber on the basic mechanical properties of concrete,analyzes the reinforcing mechanism of short-cut carbon fiber to concrete.Taking C35 ordinary concrete as the research object,the length and amount of chopped carbon fiber are variables.The basic mechanical properties of carbon fiber concrete and plain fiber concrete are compared and analyzed by slump test and static mechanical property test.The test results show that with the increase of carbon fiber content,the tensile strength and flexural strength of concrete increase obviously,the maximum increase of tensile strength is 110%,and the maximum increase of flexural strength is 36.9%.The compressive strength is reduced to varying degrees.Under the optical microscope,the carbon fiber is anisotropic in the concrete matrix material,showing a good closed space network structure.When the concrete is destroyed,it plays a good role in blocking cracks.