European Study Explores Hemp Blocks And Compaction Direction

Does the direction that hemp hurd is compacted into blocks make a difference in how well the blocks insulate and hold up under stress? That was the focus of a recent study conducted by a team of European researchers affiliated with Riga Technical University in Latvia and Lublin University of Technology in Poland. The study’s findings were published in the Journal of Natural Fibers.
“The study aims to assess the impact of variable binder content and the direction of compaction on the properties of the hemp-magnesium composites.” the researchers stated about the goal of their study. “These two factors may influence the scope of application of the developed composites (e.g. as a lightweight insulating filling of a frame wall, or a heavier material for load-bearing applications or in prefabrication).”
“Capillary rise, thermal conductivity, compressive and flexural strength in two directions, as well as the absorbability were tested. An analysis of the environmental impact of the composites was also prepared.” the team stated about their methodology.
“When a magnesium binder is used, it is possible to produce lightweight composites with low thermal conductivity (0.07 W/(m∙K)), but also heavier ones with high compressive (1.73 MPa) and flexural (0.98 MPa) strength. It is possible to improve selected parameters after changing the direction of compaction. The thermal conductivity of composites compacted in a direction parallel to the heat flow was lower by 17–25% compared to a perpendicular direction.” the researchers stated.
“The positive effects of changing the direction of compaction can be used in prefabrication by adjusting the compaction process. The impact on climate change varies significantly due to the proportion of these materials from 55.07 kg CO2 eq. to 358.64 kg CO2 eq.” the team concluded.
The study’s findings build on other recent research conducted by the Cologne University of Applied Sciences, which reportedly developed new hemp-lime building blocks potentially capable of being used as a material for load-bearing structures.
“These zones, like conventional hemp limestone blocks, are to be composed exclusively of biomass and mineral binders. According to the project participants, the aim is to create a climate-positive alternative to aerated concrete blocks or lightweight vertically perforated bricks, enabling single-shell masonry construction from rapidly renewable raw materials.” reported Allgemeine Bauzeitung in its local coverage (translated from German to English).
The Institute for Construction and Agricultural Machinery Technology at the Cologne University of Applied Sciences is developing a device that will be designed to produce compacted bricks made of hemp on a large scale. The resulting bricks will undergo testing to further explore their efficiency and application feasibility.
“In the second half of our project, we will devote ourselves to practical tests with our masonry blocks. We will erect several wall modules and examine their structural properties. In addition to properties such as load-bearing capacity, thermal insulation, and moisture behavior, we want to determine which materials, such as plaster and mortar, are compatible with the blocks and demonstrate that the blocks can be easily processed using conventional tools,” said project leader Prof. Dr. Arne Künstler from the Faculty of Architecture at the Cologne University of Applied Sciences according to Allgemeine Bauzeitung.
During a recent presentation at the International Cannabis Business Conference in Berlin, leading international cannabis industry economist, Beau Whitney, founder of Whitney Economics, provided data demonstrating that the value of the global industrial hemp industry could be $456.2 billion. Hemp being increasingly used for construction would further bolster the international hemp market’s potential.