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Abstract
Hemp concrete is a natural building material prepared from hemp shives, lime and water. It is a sustainable alternative for the traditional construction materials. This study investigated the properties and potential use of hempcrete. The research results showed that hempcrete is a non-load bearing, carbon-negative material due to low compressive strength and the renewable nature of hemp shives and carbonation process in the use phase. Overall, this study showed the potential of hempcrete as an attractive option for non-structural applications.

Sustainability
Hempcrete is a carbon sink that stocks more CO2 than it emits during the production. There are two main sources of carbon absorption. First, hemp, as a crop, absorbs CO2 as it grows. Second, the binder starts absorbing CO2 after it gets in contact with air during the mixing process. The emission balance after 240 days is negative, equal to a net absorption of 12.09 kg CO2 equivalent per square meter of hempcrete wall.

Paper Studies
First, mechanical property of hempcrete was looked into to evaluate the feasibility of using an entire fragmented hemp stem in construction. The paper performed the compressive strength for hemp concrete with different ratio of binder content. The compressive strength is ranging from 0.15 MPa to 0.83 MPa. Mixture with 5.0 kg cement and 5 kg lime shows the highest strength while mixture with zero cement performance the lowest strength. Splitting tensile strength results are similar to compressive strength which mixture with zero cement had the lowest strength while mixture with 5.0 kg cement and 5 kg lime  has the highest strength. By increasing mortar density, heat conductivity and mechanical qualities also rise.

Second, the environmental performance was investigated through a non-loading-bearing wall made of hempcrete blocks using Life Cycle Assessment. The author used X-ray Powder Diffraction to test the carbonation rate of hempcrete blocks. It found out that the carbonization rate strongly depends on the sampling depth. The CO2 capture is estimated around 12g per kg of binder. Hempcrete is a carbon sink that stocks more CO2 than it emits during the production.

Material Strength and Weakness
The strength of hemp concrete is the hemp fibers used have a strong tolerance to alkaline environments. Its lower density, lower thermal conductivity, and better acoustic insulation that differ from other conventional concrete could be advantageous to use in industry. The vegetable fibers are cheap and have a low degree of industrialization which could be beneficial for non-industrialized countries. Hempcrete is a carbon sink that stocks more CO2 than it emits during the production. It has high permeability and can easily absorb or release water vapor from the atmosphere. It allows better thermo-hygrometric conditions and decreases the risk of vapor condensation and increases thermal comfort.

Hempcrete cannot be used as load-bearing material. The mechanical durability of hemp concrete still needs to be improved. Hempcrete needs to be kept away from water. Since hemp is vegetal, the hempcrete blocks need to be protected from water and risk dampness. External walls need to be protected from the rain with sand and lime plasters to avoid rotting of shives.

Case Studies
Hempcrete is often used as building products including fiberboard, wallboard, roofing tiles, insulation, paneling and bricks. The Hemp House, located in Mullumbimby, NSW, Australia, applied with monolithic hemp the main building material, where 300mm-thick walls were made.