Wood-cement composite with addition of steatite as structural and damping material

The strength and stiffness of the wood-cement composite as an orthotropic material was experimentally investigated under uniaxial compression. The diagrams "Force (N) - Deformation (mm)" were obtained with the use of the test-machine SHIMADZU AG50kNX for 28 days old samples in the form of a cube with an edge of 10 cm. The test was stopped if a compressive strain reached 10 % (10 mm). Components of the studied material consisted of the following parts: sawdust, Portland cement, hydrated lime, sodium silicate, or calcium chloride, polypropylene fiber (segments of 18 mm length), waste soapstone in the form of powder, and water. If the deformation rate is V = 5 mm/min then a decrease in steatite additives from 10 to 15 % in the cement weight leads to a decrease in the strength 3,68 MPa to 3,43 MPa. In this case, additive micro-silica reduces the strength. With the increase in deformation speed by 30 mm/min the strength increases. If V = 90... 120 mm/min, all examined mixtures provide strength 3,62-3,72 MPa. However, if V = 180 mm/min, a combination of steatite additives and micro-silica in amount of 15 and 5 % from the weight of the cement provides the highest strength. The ratio of the strength and stiffness can be sufficient for new damping devices. The main application of the investigated variants of the wood-crete are low rise buildings, including seismic and similar man-made influences.