PSI - Issue 78

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

1348

On the other side, the problem of mortar mixing becomes serious during the installations on-site, because the correct fibers dispersion in the mixture may be compromised. Over the diagrams of Fig. 4 they have been also plotted the regression lines interpolating flexural and compression strength ratios, as a function of the fiber lengths used in the composite mortar (with reference to different fiber percentages). In this case the observed strength trends are not uniform among the analyzed cases: in some cases they are observed increases of strength as the fiber length increases while in other the strengths maintain constant or slightly reduces (as for the tests conducted by Juradin et al. 2021). On the other hand, the strength reduction is compensated by an enhanced thermal behavior thanks to the addition of the fibers making such a type of mortar performant (Majumder et al. 2023). A not secondary aspect emerged from the analysis of the technical literature is that the addition of natural fibers modifies (positively) the post-peak behavior of the material. Their addition allows to achieve more ductile behaviors, thus enhancing the energy dissipation capacity and resulting performant for seismic applications. However, this aspect is less studied and require other experimental campaigns aimed at quantifying the real dissipation capacity. 4. Concluding remarks The employment of bio-based mortars is gaining popularity in the field of construction materials, particularly due its sustainability and mechanical performances for seismic applications. In this framework, the present paper deals with an overview on the mechanical performances of natural fiber reinforced mortar, setting the state of advancement of the scientific knowledge in the field. The bibliometric analysis, conducted with reference to the time interval of the last 20 years, remarked the attentions reserved by the researchers on this topic, accompanied by a significant scientific production. The systematic literature review conducted in this paper allowed to generate a database whose data were post processed by the authors with the aim of understanding the performances of natural fiber-reinforced mortar as a function of different parameters, i.e. fiber length fiber percentage. The collected data allowed to understand as the addition of natural fibers into mortar mixture enhance the post-cracking behavior of the composite material due to the capacity of fibers into bridging the crack faces, whereas no significant effects on the increment of flexural and compression strength is always achieved. On the other side, the strength reduction is compensated by the enhancement of the thermal properties of the material which is not a secondary aspect from a sustainability standpoint. Comparing the collected data allowed to understand the role of fiber percentage (by mortar weight) and fiber length on both flexural and compression strength of the composite material. The increment of fiber length generally produces an enhancement of the strength associated to the enhanced adherence mortar and the fibers, while higher fiber percentage involves reduction of strength. Finally, the research allowed to understand the needs of other experimental tests aimed at characterizing the role of other parameters such as the effect of fiber orientation, the influence of the type of fiber, the shear strength of the composite, as well as the dissipation capacity in post-peak phase. Acknowledgements This paper was partially developed with the financial support of the research project PRIN PNRR 2022 “Multi risk analysis of the vulnerability of archaelogical sites (MiRA)” (CUP H53D23008690001).

References

Ahmad, H., Chhipi-Shrestha G., Hewage, K., Saduq, R. 2022. A comprehensive review on construction applications and life cycle sustainability of natural fiber biocomposites. Chakraborty, S., Kundu, S.P., Basak, K.R., Adhikari, B., Majumder, S.B., 2013. Improvement of the mechanical properties of jute fibre reinforced cement mortar: A statistical approach. Construction and Building Materials 38, 776-784. di Prisco, M., Colombo, M., Dozio, D, 2013. Fibre-reinforced concrete in fib Model Code 2010: principles, models and test validation. Structural Concrete 14, No 4.