Earth-based mortars for repair and protection of rammed earth walls. Stabilization with mineral binders and fibers

Abstract

Highlights  Rammed earth wall may suffer degradation with natural ageing and can be repaired with earth-based mortars  Environmental performances of earthen mortars are substantially better than cementitious mortars but their physical properties are not well known  The influence of additions of binders and hemp fibers in earth mortars is assessed  The additions of the hemp fibers decreases thermal conductivity and drying capacity  The addition of the binders increases capillarity, decreases the drying and is not significant for mechanic properties.

Bio-fibre earth composite mortar: A structural and hygrothermal assessment

“…Figure 2 that the addition of bio-fibres reduces the dry bulk density for all samples from both mix designs. This is due to the fibres having a lower density than the PL mortar, which would usually occupy the same space as the fibres -these findings are in line with experimentation by (Gomes, Faria and Gonçalves, 2018). In addition to this, the incorporation of lime into both mix designs and the cure time for these samples being only 28 days dictates that the lime is currently acting as a filler rather than a key structural element of the mix.…”

Thermal performance and fitness of glacial till for rammed earth construction

“…This is probably to avoid strength loss (due to discontinuities and interfaces) and the damage due the differential thermal and hygric expansion coefficients of the earth matrix and the gravel during environmental exposure. However, other authors do not consider the coarse fraction as a limiting factor [23].…”

“…To evaluate their thermal performance, the internal air temperature was plotted vs the external air temperature. Also, the percentage of time that the internal air temperature spent in different indices of thermal comfort in accordance with ISO 7730 [28] were evaluated as well as the annual heating loads for the different fabrics (kWh). Table 1 compares the geotechnical parameters of the till studied against other boulder clays and recommended values for RE construction.…”

“…Table 5. Percentage of year spent in the different comfort indices (heated scenario) conforming with ISO 7730 [28].…”

Sustainable bio-based earth mortar with self-healing capacity

“…Fifth International Conference on Sustainable Construction Materials and Technologies. http://www.claisse.info/Proceedings.htm Buildings respond in a variety of ways as explored in (Minke, 2013); structural cohesion deformation and cracking are associated to having direct contact with water (Bui et al, 2009) for example: due to weathering, thermal expansion and shrinkage, mechanical impact or due to the earths inherent biological susceptibility (Gomes, Faria and Gonçalves, 2018). These key issues affecting earth construction can be organised into 3 categories: structural, environmental and chemicalwhich have been tabulated within Table 1.…”