Campione, Universita di Palermo, Italy G. Target readers: graduate students, researchers, fiber producers, design engineers, material scientists. However, information about the shear behaviour of high-performance fibre-reinforced cementitious composites beams is very limited, because most studies were focused on their flexural behaviour. The average compressive strength tested on 100 mm side cubic specimens and the age of testing are also given in Table 1. The ductility of the as-built frame was limited due to pullout of poorly embedded positive moment reinforcement in the joint and shear inadequacy in the joint and beam.
The highly-stressed volume in pullout test is defined as the volume of a cylindrical column as shown in Fig. The cylindrical specimens were loaded in monotonic tension at strain rates ranging from quasi-static to 0. Barros Impact Behavior of 3D Fabric Reinforced Cementitious Composites. Explanations about how the different fibres, matrix properties, test factors and environmental conditions can affect the adhesion results are given. This paper analyzes the adhesion theory for fibre reinforced cementitious composites to separate the share of the chemical and mechanical adhesion expressing new parameters, which are effective in the adhesion behaviour.
Flexural tests on two types of composites Fig. They also demonstrated more ductile flexural behavior compared to normal concrete from three-point bending test. The typical stress-elongation response of a fiber reinforced cement composite indicate two properties of interest, the stress at cracking, σ cc , and the maximum post-cracking stress σ pc Fig. This procedure reveals that there is not a monotonic decrease of the residual modulus of elasticity with number of cycles. Although the walls in both specimens exhibited a flexural-dominated behavior, shear distortions in the first story of the walls reached 0. Dynamic Properties and Damage Model of Ultra-High Performance Fiber Reinforced Cement Composites Subjected to Repeated Impacts J.
In this model, the total shear resistance of the steel-fiber-reinforced concrete flat slab is expressed by sum of the shear contribution of steel fibers in the cracked tension region and that of intact concrete in the compression zone. Similarly, there is not a monotonic increase of the residual maximum compressive strain. Since the process of estimating the Strength Dependent Tensile Behavior of Strain Hardening Fiber Reinforced Concrete 7 number of cracks could be highly subjective, the number of cracks is counted from both front and back surface of specimens and the numbers are averaged. A simplified design equation was developed from the analytical results to express the dependence of the concrete contribution term on the intensity of imposed deformation demand. The primary objective of this International Workshop was to provide a compendium of up-to-date information on the most recent developments and research advances in the field of High Performance Fiber Reinforced Cement Composites. Experimental and Nonlinear Finite Element Analysis of Fiber-Cementitious Matrix Bond-Slip Mechanism C.
Five large scale bridge columns are subjected cyclic lateral loading to verify their responses and deformation capacity. Si Larbi Bond Behavior of Textile Reinforcements - Development of a Pull-Out Test and Modeling of the Respective Bond versus Slip Relation. The stress-strain relationship of concrete in compression in both unconfined and confined states was examined. Standard methodology and classification proposed are in accordance with the evolution of concrete and unify historic milestones achieved by the international research community. The authors acknowledge the kind support of Okumura Corporation and Techno Material Co.
The model was used to conduct a parametric investigation of several design variables. Besides, the connections represent the construction process stage developed in situ, during which common problems at the structure assemblage process have to be faced. The additional hydration possibly occurred by the unhydrated materials in the composite as well as the reactive components in the pore solution of mortar which filtrated into the composite. The crack distribution, failure pattern, load-displacement responses, flexural capacity analysis, displacement ductility and concrete strain are investigated. Extreme care was taken when positioning and aligning the fiber symmetrically during the first stage of casting. It should be considered as the minimum amount of steel cords which can lead to the formation of multiple cracking and strain hardening under tensile actions.
The detailed mixing procedure for M4 is described by Wille et al. The addition of closely spaced and uniformly dispersed small fibers to concrete would act as crack arrester and would sub-stantially improve its mechanical behavior and ductility. However, at the final stage of the tests there was no evidence of bond failure in the splice regions. The test results revealed that the inclusion of short fibers can significantly increase both strength and ductility under uniaxial and biaxial loading paths, but that the role of volume fraction is rather small for the range of fiber volume contents considered. However, it is believed that these standards or methods do not comprehensively describe the flexural performance of fiberreinforced concrete, because each only reports on part of the information.
The study shows that the use of ultrahigh strength longitudinal reinforcement in frame members is a viable option for earthquake-resistant construction. The crack bridging stress was found to decrease with the increase of loading cycles. Ishikawa 67 An Investigation of Mechanical Properties of Jute Fiber-Reinforced Concrete. The comparative results demonstrated that the new shear model presents a more reasonable assessment accuracy and higher reliability. Multifunctional Carbon Black Engineered Cementitious Composites for the Protection of Critical Infrastructure M.
Their diameter was nominally equal to 20 mm Fig. This test evaluates the energy failure during the fibre drawing out. Fine aggregate is silica sand. The beam stiffness was about 85% of the initial beam stiffness at flexural cracking state and was only approximately 25% of the initial beam stiffness at the ultimate state. A design detail of the test elements is shown in Fig. With her team, she has successfully carried out over 50 important national or international projects and co-authored more than 400 technical publications.
In addition to evaluating a different precast coupling beam embedment detail, the second coupled-wall specimen also incorporated fiber reinforcement in the first two stories of the cast-in-place walls, which allowed for a reduction of transverse reinforcement for confinement and a higher concrete contribution to shear strength in the plastic hinge region. The influence of jacketing schemes and axial load ratio on the failure modes, hysteresis loops, skeleton curves, deformation capacity and energy dissipation capacity is analyzed respectively. One portion of the specimen was initially cast, with the fiber located precisely at the specified position and allowed to cure in room temperature. The contributions of the parameters affecting the shear strength were evaluated through a sensitivity analysis. The primary joint details investigated are two-part U-shaped stirrups passing through holes in the web of the steel beams, steel band plates or cover plates surrounding the joint region, steel fiber concrete or engineered cementitious composite material in the connection, and bearing bars attached to the steel beam.