Investigations on thermal and mechanical properties of cement mortar with reed and straw fibers

Abstract

Building insulation is commonly realized using materials obtained from petrochemicals or from natural sources processed with high energy consumptions, causing significant harmful effects on the environment. The "sustainability" applied to building design has encouraged many researches to develop thermal and acoustic insulating materials using natural or recycled materials. Many natural materials were already used in ancient times to thermally insulate the dwellings and to give resistance: straw and reed are some representative examples. Aim of this paper is to evaluate the influence of reed stems and straw on the thermal and mechanical performances of cement. To reach this, several types of mixes were prepared: a specimen as reference mix without any addition of fibers and some more specimens with reed only, with straw only, and finally the combination between straw and reed in different percentage. The tests were performed to determine the thermal conductivity, the compressive and flexural strength of the cement mortar panels. The results showed that straw, if combined with reed stems, could be considered as a valid reinforcement in a cementitious matrix characterized by enhanced thermal insulation and good mechanical properties. ENEA researchers have also applied a statistical method to the obtained test results in order to develop a predictive model of compression and flexural behavior of fiber-reinforced specimens with different percentages of organic fibers in the mixture cementitious.

Clay and fibers: Energy efficiency in buildings between tradition and innovation

“…Furthermore the final values of thermal conductivity λ decrease from 30 to 40% with respect to the REF-p. Comparing the obtained results with those of a previous work [12] it is possible to notice that the sand/clay matrix has a better thermal behavior than a cement mortar.…”

“…In the last decades, extensive studies have been done especially on the effects of natural fibers on the mechanical and physical behaviour of cementitious materials in terms of strength, energy efficiency, and impact resistance [11][12]. The inclusion of short discrete fibres in concrete, mortar and/or cement paste can largely enhance some of their engineering properties, such as fracture toughness, tensile strength, flexural strength, resistance to fatigue, impact, and thermal shock [13].…”

Energy and Mechanical Characterization of Composite Materials for Building with Recycled PVC

“…The test equipment used for both types of mechanical tests was a Dual Column Instron 3369 frame [14]. The instrumentation applies the load at a specified speed: For each sample the maximum applied load was recorded and expressed in Newton; the bending and compressive strength was calculated to the nearest 0.05 N/mm 2 .…”

Thermophysical characterization of a cardboard emergency kit-house

“…They were used by the Civil Protection agency during the seismic crisis which hit the regions Marche and Umbria in 1997 [9][10]. The sector of the emergency shelter may constitute an huge opportunity to investigate and characterize new eco-friendly material [12][13], as well for introducing innovative solution in the shelter enevelope [14][15].…”