Research on Chloride Penetration Resistance of Hybrid Fiber Reinforced Self-Compacting Concrete
The properties of chloride penetration of hybrid fiber reinforced self-compacting concrete (SCC) were investigated in this study. The results show that the chloride penetration resistance of concrete can be improved by single incorporation either carbon or cellulose fibers. The concrete chloride diffusion coefficient DRCM of 12-cm length carbon SCC with fiber content of 1.7, 2.72, and 3.4 kg/m3 decreases by 10.3, 25.5, and 18.2% compared to reference concrete without any fibers, respectively. Moreover, the concrete chloride diffusion coefficient DRCM of cellulose SCC with fiber content of 1.2, 1.6, and 2.0 kg/m3 decreases by 18.8, 22.4, and 26.7% compared to reference concrete, respectively. Based on the results of orthogonal experimental design, the chloride diffusion coefficients DRCM of hybrid fiber reinforced SCC are listed in order of importance, as follows: length of carbon fiber > content of carbon fiber > content of cellulose fiber; furthermore, the hybrid of 2.72-kg/m3 carbon fiber with length of 12 mm and 2.0-kg/m3 cellulose fiber exhibits the most significant effect on chloride diffusion coefficients DRCM of SCC.
Current State Of Fibre Rein forced Self-Compacting Concrete
The relative compressive strength of concrete is high and tensile strength is low is a well-known fact, which provoked a host of investigations to circumvent the problems created by the low tensile strength. The presence of micro cracks hastened the relatively faster failure of concrete and researchers have been relentlessly working on this issue and came up with solutions like putting in fibers along with main reinforcement, whether natural or manufactured. The distributed fibres act as a bridge between micro-cracks leading to the improved mechanical properties such as ductility, impact strength, toughness, tensile strength and fatigue resistance. Moreover, the development of self-compacting concreter has enhanced the flowablity of concrete at all nukes and corners. A combination of FRC and SCC has created a composite known as FRSCC to annihilate the negativities of both.
Direct assessment of tensile stress-crack opening behavior of Strain Hardening Cementitious Composites (SHCC)
The process of designing Strain Hardening Cementitious Composites (SHCC) is driven by the need to achieve certain performance parameters in tension. These are typically the pseudo-strain hardening behavior and the ability to develop multiple cracks. The assessment of the tensile load-deformation of these materials is therefore of great importance and is frequently carried out by characterizing the material tensile stress-strain behavior. In this paper an alternative approach to evaluate the tensile performance of SHCC is investigated. The behavior of the material in tension is studied at the level of a single crack and the tensile performance is evaluated in terms of the tensile stress-crack opening behavior. The experimental procedure and test setup used are discussed. The derived tensile stress-crack opening behavior is utilized to analyze and compare the influence of various composite parameters on the resulting tensile behavior. The deformations occurring during tensile