钢纤维增强橡胶高强混凝土强度试验研究

利用超声回弹检测技术,对3种不同钢纤维掺量的钢纤维增强橡胶高强混凝土试件进行超声波回弹测试和抗压强度试验,得出钢纤维橡胶高强混凝土的超声回弹综合法的专用测强曲线,为利用超声回弹检测技术对钢纤维增强橡胶高强混凝土的强度测试提供技术参考.     

钢纤维橡胶高强混凝土性能实验研究

实验研究了钢纤维高强混凝土的坍落度和密度,对钢纤维高强混凝土、钢纤维橡胶高强混凝土试件进行轴心抗压强度试验,研究了橡胶粉掺量及粒径对钢纤维高强混凝土抗压强度和变形能力的影响。     

橡胶改性钢纤维高强混凝土高温力学性能研究

将再生橡胶粉掺入钢纤维高强混凝土中进行改性,通过对橡胶改性钢纤维高强混凝土试件600℃高温后的外观变化、质量损失、轴心抗压强度、变形特性等的试验研究,探讨不同橡胶掺量、粒径对钢纤维高强混凝土抗爆裂性能的影响。研究结果表明:低熔点的橡胶粉能有效地改善钢纤维高强混凝土的韧性及高温爆裂性能,可广泛应用于对抗裂及耐火要求较高的高层及大跨结构中。     

超短异型钢纤维高强混凝土性能研究

本文通过对比试验研究,探讨了超短导型钢纤维高强混凝土的力学性能和超声波速。证明超短异型钢纤维高强度混凝土可以解决钢纤维混凝土的搅拌均匀问题,并且适应现代化施工要求,从而可改善高强混凝土的抗拉抗剪强度,提高混凝土韧性;提出了采用超声测试技术可以推断钢纤维的掺入量和分布的观点。     

超声技术在钢纤维混凝土中的试验研究

本文通过对一批C40钢纤维混凝土试件进行超声波检测及抗压强度的试验研究,对试验结果进行了回归分析,建立了钢纤维混凝土检测的超声波声速与抗压强度之间的关系曲线,结果表明:利用该曲线测定超声声速可推定钢纤维混凝土的强度,超声波检测方法用于钢纤维混凝土无损检测是可行和适用的。     

高强混凝土和钢纤维高强混凝土断裂性能试验研究

通过对C80高强混凝土（HBC）和钢纤维高强混凝土（SFHSC）试件断裂性能的测试，分析两类混凝土断裂性能特性，并通过多指标与普通混凝土比较，总结HSC和SFHSC的断裂性能。     

钢纤维改性再生橡胶高强混凝土性能试验研究

以钢纤维作为改性材料掺入到再生橡胶高强混凝土中,通过试验研究了钢纤维橡胶高强混凝土的力学性能,包括抗压强度、劈裂抗拉强度和抗折强度.试验结果表明:钢纤维的掺入,可有效地提高橡胶高强混凝土的力学性能和延性,改善高强混凝土由于橡胶粉掺入所导致的强度降低的影响.     

超短钢纤维高强混凝土静力与动力抗压特性对比试验及分析

采用长度9mm、直径约0.45mm的平直型超短钢纤维,研制了钢纤维体积含量0%、3%和6%的钢纤维高强混凝土,对它们进行了准静态的压缩试验和冲击压缩试验,得到两种材料在不同应变速率下的全过程应力应变曲线,对比分析了静态和动态条件下钢纤维含量对超短钢纤维高强混凝土的影响。     

钢纤维高强混凝土抗压强度影响因素

通过钢纤维高强混凝土立方体抗压试验,探讨了粗集料最大粒径、水灰比和钢纤维体积率对钢纤维高强混凝土抗压强度的影响.结果表明:钢纤维掺量不同,粗集料最大粒径变化对抗压强度影响趋势不同;随着水灰比的减小,抗压强度逐渐增加;随着钢纤维体的增大,抗压强度逐渐增加.在分析试验结果的基础上,分别建立了水灰比、钢纤维体积率与抗压强度之间的关系式.     

钢纤维高强混凝土的力学性能研究

通过掺入体积含量０ ．６ ％ ～１．８ ％ 的短切钢纤维,与Ｃ６０ ～Ｃ８０ 高强混凝土复合,制作钢纤维高强混凝土。研究了钢纤维高强混凝土的抗压、劈拉和抗弯强度以及抗弯韧性指数等参数的规律。探讨了钢纤维高强混凝土的强度复合机理和力学特性。     

Parameter optimization on compressive strength of steel fiber reinforced high strength concrete

This paper illustrates parameter optimization of compressive strength of steel fiber reinforced high strength concrete (SFRHSC) by statistical design and analysis of experiments. Among several factors affecting the compressive strength, five parameters that maximize all of the responses have been chosen as the most important ones as age of testing, binder type, binder amount, curing type and steel fiber volume fraction. Taguchi analysis techniques have been used to evaluate L₂₇ (3¹³) Taguchi’s orthogonal array experimental design results. Signal to noise ratio transformation and ANOVA have been applied to the results of experiments in Taguchi analysis. The confirmation runs were conducted for the optimal parameter level combination, which is obtained from the results of the above methodologies. The maximum compressive strength has been observed as around 124 MPa. By using the optimal parameter level combination, the direct tensile strength and flexural strength tests have been conducted. The mean values at the age of 28 days are obtained as 7.5 MPa and 13 MPa respectively. In this study, it is clearly demonstrated that all main factors except steel fiber significantly contribute to the compressive strength of steel fiber reinforced high strength concrete, yet age and binder type are the most significant contributors.     

超短钢纤维混凝土动态力学性能研究

利用φ74 mm的变截面SHPB装置对钢纤维长6mm,长径比40,钢纤维体积含量分别为0%、3%、6%的超短钢纤维混凝土进行了冲击压缩试验,得到了不同应变率下的全过程应力应变曲线.试验结果表明：随着钢纤维含量和应变率的提高,钢纤维混凝土的峰值应力增加.结合试验现象,通过分析微裂缝的萌发与扩展的原理对钢纤维的增强机理及应变率效应进行了阐述.     

高温中钢纤维混凝土抗压强度试验研究

综述了国内外混凝土及纤维混凝土高温后及高温中的性能变化规律。研究了3种水胶比混凝土及钢纤维混凝土在20、200、400、600、800℃五个温度段高温中的抗压强度,结果表明:素混凝土及钢纤维混凝土高温中抗压强度都呈先升高再降低趋势,素混凝土和钢纤维混凝土分别在200、400℃时达到峰值,400℃时钢纤维的增强效果最明显。     

钢纤维高强混凝土抗压性能试验研究

通过对高强混凝土和钢纤维高强混凝土试件的试验,研究钢纤维类型和钢纤维体积率对高强混凝土立方体抗压性能的影响。结果表明:钢纤维类型和体积率对高强混凝土立方体抗压强度均有一定的影响,钢纤维高强混凝土立方体抗压强度的尺寸效应与普通强度钢纤维混凝土基本相同。     

钢纤维混凝土冲击压缩韧性

利用Φ100 mm SHPB装置分别对60 MPa 强度等级的素混凝土及钢纤维掺量分别为0%,0.2%,0.4%和0.6%的混凝土进行冲击压缩试验,控制在 10/s～20/s,30/s～40/s和75/s～90/s的应变率范围内.以峰值应变和残余强度法,作为韧度评价指标.峰值应变基本随钢纤维含量增加而增加,但随应变率的上升,钢纤维含量对峰值应变的影响减弱.对于C60系列,准静态下,最大增强27% (C60V4),83/s时,最大增强7%(C60V2);应变率86/s左右时,峰值应变基本与钢纤维含量无关.同样,残余强度对应的应变值明显随纤维含量增加而增加,反映出钢纤维的增韧效果.     

Experimental behaviour of steel fiber high strength reinforced concrete and composite columns

This paper presents experimental behaviour of eccentrically loaded plain and steel fiber high strength reinforced concrete and concrete-encased composite columns. In the experimental study, a total of 32 square section both reinforced concrete and composite column specimens were fabricated at 0, 0.5, 0.75 and 1.0% volume fractions of steel fiber contents to examine the effects of steel fibers on column behaviour. Besides this, the composite columns were constructed and tested using almost the same conditions with reinforced concrete columns to investigate the column experimental behaviour. The complete load−deflection behaviour and strength of column specimens were obtained and the results were discussed in the study. In addition, the column specimens were analysed based on a theoretical method considering the nonlinear behaviour of the materials. The presented experimental study indicates that the inclusion of steel fibers in the range 0.75 to 1.0% volume fraction improves confinement and ductility features of high strength reinforced concrete and composite columns significantly.     

钢纤维高强混凝土抗弯试验研究

对钢纤维体积率(Vf)为0~3%的钢纤维高强混凝土(SFRHSC)进行抗弯性能测试,试验结果表明,SFRHSC试件整个破坏过程类似于钢筋混凝土适筋梁,且Vf越大,延性破坏特征越明显,荷载-挠度曲线的峰值越大,下降段越平缓。SFRHSC的抗弯强度和韧度均显著高于普通高强混凝土,而且极限抗弯强度与初裂抗弯强度的差值随Vf的提高而增大,但抗弯弹性模量未有明显的变化。     

钢纤维高强混凝土研究与应用进展

介绍了钢纤维高强混凝土的增强机理以及工程应用的实例,对目前钢纤维高强混凝土的研究与应用情况进行了分析与总结,对钢纤维高强混凝土的应用前景进行了探讨,提出了一些研究与应用过程中有待解决和提高的问题.     

Effect of matrix strength on pullout behavior of steel fiber reinforced very-high strength concrete composites

This paper presents the results of single-fiber pullout tests for deformed and smooth steel fibers embedded in the newly developed very-high strength concrete (VHSC) matrixes. The pullout test program involved four types of steel fibers, eight compressive strengths of VHSC matrixes, and two normal concrete strengths. Test results have shown that pullout behavior of different steel fiber reinforced VHSC composites is influenced by the matrix strength and fiber end condition (smooth, flat end, or hooked). Results reveal that both maximum pull-out load and total pullout energy increases as matrix strength increases for all deformed fibers that did not rupture. The test results also indicated that the increase in total pullout energy is more significant than that in peak load.