Jute fiber reinforcement for masonry walls: Integrating structural strength and thermal insulation in sustainable upgrades

Existing masonry buildings require appropriate structural and thermal upgrading to meet structural safety and energy efficiency according to the current standards. Textile Reinforced Mortar (TRM) presents several advantages for masonry strengthening, but the production of man-made fibers is often expensive and environmentally harmful. For this reason, this work reports on the integrated (structural and thermal) upgrading of the hollow-clay brick masonry walls strengthened with jute Natural Fiber (NF) TRM system configured with jute fiber nets, jute fiber diatons and jute fiber composite mortar. The shear strength capacity and ultimate strength of these upgraded masonry walls have been evaluated through in-plane cyclic shear tests, whereas a constant vertical load was applied. Furthermore, the thermal performance of the same upgraded masonry walls has been evaluated through thermal conductance measurement, by using a climate chamber with pre-set environmental (internal/room and external/ambient) conditions. Masonry wall specimens were upgraded with NFTRM system package and the package consists of fiber nets (with mesh 2.5 cm × 2.5 cm, one on each side), jute fiber diatons (four), and jute fiber composite mortar (of the combination of 1 % jute fiber with respect to the dry mortar mass and 30 mm fiber length). Improvements in both ultimate strength and thermal insulation of the NFTRM-upgraded masonry walls have been observed as part of the integrated (structural and thermal) behavior assessment. Due to the application of jute fiber composite layers of the NFTRM system package (jute fiber nets, jute fiber diatons, and jute fiber composite mortar) the overall withstanding load capacity increased by more than 525.00 %, whereas the thermal transmittance value was reduced by 36.05 % (representing the improvement of insulation capacity) when compared with the masonry wall without upgrading.