PSI - Issue 78

Sandoli Antonio et al. / Procedia Structural Integrity 78 (2026) 1342–1349

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splitting tests. Moreover, scanning electron microscopic analysis was carried out founded that hemp fibers had good adherence to cement due to their geometrical shape. Trochoutsou et al. 2021 tested flax and jute textile-reinforced mortars concluding that when mechanical reinforcement ratios greater than 3% are provided, flax textiles with smaller diameter and twisted yarns, arranged in denser meshes, ensure good composite action. Majumder et al. 2023 performed an extensive experimental campaign aimed at characterizing the mechanical behavior of jute fiber-reinforced mortar from mechanical and thermal standpoint. They used three different fiber lengths (5 mm,10 mm and 30 mm) and four different fiber percentages (0.5%, 1.0%, 1.5% and 2.0%) with respect to the mortar mass. The study highlighted that the addition of fibers into the mortar mixture increases its porosity and reduces the density: consequently, flexural and compressive strength of the composite material reduce with respect to the unreinforced one. Moreover, the research pointed out that the presence of the fibers tends to improve the strain energy capacity of samples yielding to flexural and compressive ductile behavior in comparison to not reinforced mortars, a parameter particularly useful for seismic applications. Pepe et al. 2023 conducted an interesting study aimed at the mechanical characterization of natural textile-reinforced mortar arranged consisting with lime-based matrices and natural fabrics such as jute fibers and flax yarns. Research results proved that the tensile response of reinforced mortar samples is affected by the mechanical properties of reinforcing material: the flax yarn tends to outperform the jute fibers in terms of both maximum bending strength and overall post-cracking toughness. Instead, the experimental behavior of hemp and broom spanish fiber-reinforced mortar samples was investigated by Jouradin et al 2021. The fibers were treated with alkali, seawater and a combination of alkali and seawater to change the fiber structure. The results underlined that natural fibers do not have a significant influence on the mechanical properties of the mortar (compressive and flexural strengths), whereas its ductility increases. Moreover, the study highlighted that the addition of lower portion of fibers in the mixture enhance the mechanical properties compared with the composite material with higher portion of fibers. Similarly, also the specimens containing lower fiber percentage experienced higher ductility than those with higher fibers percentage. Sandoli et al. 2025, instead, investigated the mechanical performances of broom fiber-reinforced cementitious mortars by using two different fiber lengths (15 mm and 20 mm) and with a fiber percentage equal to 0.50% by mortar mass. The study concluded that flexure and compression strength of reinforced mortar reduce with respect to unreinforced one, highlighting as the mortar mixing plays a fundamental role into avoiding the formation of fiber nests responsible of strength reduction.

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Natural fiber reinf. mortar FRP reinforced mortar

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Numb. of papers

Numb. of papers

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Italy

Spain

Germany Japan

Serbia

France

Poland

Turkey

Canada

Ethiopia

Saudi Arabia Belgium

Morocco

Malaysia

1995 2000 2005 2010 2015 2020 2025 2030

South Korea

Year

Czech Republic

North Macedonia

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b)

Fig. 2. Number of papers about natural fiber reinforced mortar: a) by countries, b) by years.