The current study aims to assess the shear behaviour of reinforced mortar beams including Polyvinyl Alcohol Fibre (PVA) ranges from 0 to 2.25%, fly ash (55%) and silica fume (15%). Fourteen beams were experimentally tested under two concentrated loads. In addition, a finite element model was developed to predict the crack pattern, load–deflection, energy absorption, and shear strength results of the test beams. The studied variables were different percentages of PVA fibres, shear span to depth ratio (a/d), and transverse reinforcement (stirrups) ratio. The fly ash and silica fume were kept constant in all the studied mixes to achieve a compressive strength above 55 MPa at the time of testing (90 days) and to improve PVA-mortar properties. It was found that the inclusion of PVA improves the shear behavior of the tested beams in terms of crack pattern and ductility. It was observed also that reducing a/d led to enhancing the shear capacity without changing the mode of failure. In addition, PVA played the same role as the stirrups and their effect on the ultimate shear capacity was increased with reducing the volume of stirrups. Moreover, the PVA fibres were more effective in lower shear span to depth ratio (a/d = 1.5) giving an enhancement of shear resistance of 221%. The non-linear finite element model showed excellent agreement with the experimental results and the ratio of the predicted to experimental ultimate strength ranged between 0.91 and 1.09. The authors recommend a combination of fly ash, silica fume and at least 1.5% PVA in the presence of minimum stirrups reinforcement (5\(\Phi\)6/m) or adding 2.25% PVA without stirrups to achieve adequate shear behaviour and to improve the ductility of PVA-mortar beams.

当前的研究旨在评估增强砂浆梁的剪切性能，包括聚乙烯醇纤维（PVA）范围从0到2.25％，粉煤灰（55％）和硅粉（15％）。在两个集中载荷下，通过实验测试了十四个梁。此外，开发了一个有限元模型来预测测试梁的裂缝模式，载荷-挠度，能量吸收和抗剪强度结果。研究的变量是不同百分比的PVA纤维，剪切跨度与深度之比（a / d）和横向钢筋（箍筋）的比例。在所有研究的混合物中，粉煤灰和硅粉均保持恒定，以在测试时（90天）达到55 MPa以上的抗压强度，并改善PVA砂浆性能。已经发现，在裂纹图案和延展性方面，PVA的加入改善了测试梁的剪切性能。还观察到减小a / d可以提高剪切能力，而不会改变破坏模式。此外，PVA与马stir具有相同的作用，并且随着马stir的减少，它们对极限剪切能力的影响也增加了。此外，PVA纤维在较低的剪切跨度与深度之比（a / d = 1.5）使得抗剪强度提高了221％。非线性有限元模型显示出与实验结果极好的一致性，预测极限强度与实验极限之比在0.91至1.09之间。作者建议在最少的箍筋增强情况下（5 \（\ Phi \） 6 / m）或粉煤灰，硅粉和至少1.5％PVA的组合使用，或在不添加箍筋的情况下添加2.25％PVA以达到足够的剪切性能，并提高PVA砂浆梁的延展性。