Fiber pullout model for aligned hooked-end steel fiber

Abstract

The main objective of this study is to derive an analytical model for the pullout behavior of hooked-end steel fiber. The pullout behavior of hooked-end steel fiber comprises a component due to interfacial bond stress at the fiber–matrix interface and a component due to mechanical anchorage at the hook end of the fiber. To study the first component, the effects of hooks on the distributions of the force and stresses along the fiber length are analyzed. Then these results are used, with the concept of bond shear stress versus slip relation between fiber and matrix, to obtain a force component due to the interfacial bond. After that the required theoretical relations are obtained to determine the component due to the mechanical anchorages. Finally, the model is validated with two existing experimental results on the hooked-end steel fiber pullout. The results show that the proposed model is able to estimate the pullout behavior of hooked-end steel fiber.

Analysis and modelling of mechanical anchorage of 4D/5D hooked end steel fibres

“…Sujivorakul et al [20] extended the straight fibre pull-out model developed by Naaman et al [21] by adding a non-linear spring at the end of the fibre to simulate the mechanical anchorage contribution. In later work Laranjeira et al [22], Ghoddousi et al [23], and Lee et al [12] proposed new models which are quite comparable to the model developed by Alwan et al [18]. Soetens et al [24] have proposed a semi-analytical model to predict the pull-out behaviour of hooked end steel fibres based on the principle of virtual work developed by Chanvillard [19].…”

Comparisons Between Pull-Out Behaviour of Various Hooked-End Fibres in Normal–High Strength Concretes

“…In recent work, (Laranjeira et al 2010;Lee et al 2010;Ghoddousi et al 2010) proposed alternatives to the pulley model of Alwan et al (1999). Zīle et al (2013) developed an analytical model to simulate the mechanical contribution from fibre geometry to the pull-out response of crimped and hooked-end steel fibres.…”

Different methods to model the post-cracking behaviour of hooked-end steel fibre reinforced concrete

“…(2) Alternative to inverse analysis, another model is developed to calculate the axial crack bridging ability of SFRC based on the single fibre pull-out response of hooked-end steel fibres and hence to obtain the Mode I constitutive law for further design calculations. The fibre pull-out response of a steel fibre, both straight and deformed, embedded in a concrete matrix has been widely investigated in the past [12][13][14][15][16][17][18][19][20]. Thereby, attention is given to the influence of the type of fibre, the concrete strength and the inclination of the pull-out force.…”