Experimental investigation on mud bricks reinforced with natural additives under compressive and tensile tests

- Effect of natural fibers on the compressive strength, Young's modulus, proper durability against water and tensile strength of brick.
- The durability against water of fibrous specimens is more than simple specimens.
- Specimens with wood chips, showed no significant reduction and increasing in compressive stress.
- Wood chips excess amount makes disorder of the clay cohesion performance and the particles friction by making distance between the soils components.
- The compressive strength of palm fiber additive specimens showed the best performance among the natural additives.

In this paper, the experimental behaviour of mud brick reinforcement is present. The effect of natural fibers such as straw, wood chips carpentry, rice husk and palm fibres on the compressive strength, Young's modulus, proper durability against water and tensile strength of brick samples were given. Different amount of fibres were selected to test: 0.3 and 0.6 and 0.9 percentages of specimens' weight. The amounts of each component which may be effect the mechanical behaviour of mud bricks were investigated. In accordance with the results, the best sample in terms of compressive strength and durability against water is determined.In this investigation, the compressive strength and tensile strength of mud brick is studied. For the compressive strength the cubic samples with dimensions of 22 × 22 × 7 cm and 22 × 11 × 7 cm, and for the tensile strength the cylindrical samples with a diameter of 15 cm and height 30 cm were tested. The compressive strength of simple sample mud brick is 4.4 MPa. The compressive strength of the samples with natural additive is between 2.67 and 16.53 MPa. The durability against water of simple specimen is 255 min and the sample with 0.9 percent of weigh rice husk is 560 min. The natural additives increase the tensile strength from 57 to 281 percent.