Cristelo N et al., Influence of fibre reinforcement on the post-cracking behaviour of a cement-stabilised sandy-clay subjected to indirect tensile stress, Construction and Building Materials, Elsevier, 138: 163-173, 2017. 2 3 Influence of fibre reinforcement on the post-cracking 4 behaviour of a cement-stabilised Sandy-Clay subjected to 5 indirect tensile stress 6 7 8 a,22 23 24 25Cristelo N et al., Influence of fibre reinforcement on the post-cracking behaviour of a cement-stabilised sandy-clay subjected to indirect tensile stress, Construction and Building Materials, Elsevier, 138: 163-173, 2017. Abstract 26 27 An experimental campaign was carried out to determine the influence of polypropylene fibre 28 content and length on the post-cracking response of a Sandy-Clay stabilised with different 29 cement contents. Three main sets of specimens were prepared: cement-stabilised specimens 30 with two cement contents (5% and 10%); fibre-reinforced specimens with three fibre contents 31 (0.1%, 0.2% and 0.3%) and cement-fibre-reinforced specimens combining the mentioned fibre 32 and cement contents. Tensile tests on the fibres and indirect tensile tests and triaxial 33 compression tests on the prepared specimens were conducted. Results show that the post-34 cracking behaviour is strongly affected by the combination of fibre and cement content as well 35 as fibre length. Pull-out was the governing failure mode. Post-peak tension loss rate increased 36 with fibre content, as a result of the loss of influence of the fibres on the post-peak behaviour.
37On the contrary, an increase in fibre content resulted in higher pre-peak strength gain rates and 38 higher peak stresses. 39 40 41
Cement stabilisationCristelo N et al., Influence of fibre reinforcement on the post-cracking behaviour of a cement-stabilised sandy-clay subjected to indirect tensile stress, Construction and Building Materials, Elsevier, 138: 163-173, 2017. 4 complex material in terms of tensile strength, especially on the post-peak stress segment of the 70 load-displacement curve. This structural response has not yet been fully characterised, and is 71 thus the main subject of the present paper. 72 73 In general, the fibres are responsible for an increase of the compressive and shear strength, 74 especially at the post-peak and residual (post-cracking) stages, and the extent of such 75 improvement is intrinsically dependent of several factors, such as: fibre properties, geometry 76 and content; fibre distribution and orientation within the matrix; existence and magnitude of 77 artificial cementation (using, for instance, Portland cement or lime); and fibre-soil bonding 78 (stress-slip behaviour).79 80 The present paper aims a thorough characterisation of the tensile stress post-peak response of a 81 polypropylene fibre reinforced sandy-clay. It is part of an extensive research programme 82 designed to understand the mechanical response of a very common Portuguese soil, when 83 reinforced with fibres, as well as the potential need for additional chem...