Effect of rising damp in unstabilized rammed earth (URE) walls

Abstract

The effect of rising damp on the Thermal-hydro-mechanical (THM) behavior of Unstabilized Rammed Earth (URE) structures has been rarely studied in literature. To consider this effect, we use a validated theoretical framework implemented in a finite element code for the THM behavior of URE materials. The effect of rising damp is then investigated and compared with the same wall not influenced by the rising damp. The simulation results show that time plays a positive role on the THM properties of an URE wall because the evaporation process reduces the humidity, decreases the water content, increases the thermal insulation and improves the mechanical strength of the wall. In contrast, the rising damp plays an opposite role since it has a cooling effect on the wall temperature. The wall dries more quickly and the water also flows fast to the bottom side of the wall. Without rising damp, the horizontal bearing capacity increases 47% when the time passes from 7 days to 1825 days after construction, while this increase is only 10% with the rising damp. The decrease of thermal insulation resistance and hydraulic conductivity becomes less in the wall with the rising damp after five years.