脆性材料往往有微裂纹，在拉力作用下沿着与裂纹平面垂直的方向扩展。 在这

Brittle materials often have micro-cracks, which propagate in a direction perpendicular to the crack plane under the action of tension. Under pressure in this direction, the crack will close to some extent. Therefore, brittle materials are more likely to break in the stretched state than in the compressed state, so the tensile toughness is lower than the compressive strength, and the tensile ductility is lower than the compression ductility (Figure 3.10). On the other hand, the compressive and tensile modulus can be comparable because elastic deformation does not involve crack propagation. Because of its low tensile strength, the brittle material is best used in a compressed state rather than in a tensile state. It is expected that the brittle material part that will encounter tensile stress needs to be strengthened. This is why reinforced concrete (embedded reinforcement) of concrete (a brittle material) is widely used. The reinforcement is located in the part of the concrete member that encounters tension.

Fragile materials tend to have microcracks and extend in a direction perpendicular to the crack plane under the action of the pull. Under pressure in this direction, the cracks close to some extent. As a result, brittle materials break more easily in stretching than in compression, so stretch toughness is lower than the pressure strength and stretch elongation is lower than compression ductility (Figure 3.10). On the other hand, compression and tensile modulus can be comparable because elastic deformation does not involve crack expansion. Due to its low tensile strength, brittle materials are best used in compressed rather than stretched states, and it is expected that the brittle material parts that will encounter tensile stress will need to be strengthened. This is why reinforced concrete (embedded reinforced reinforcement) of concrete (a brittle material) is widely used, and the reinforced steel is located in the tension-like part of the concrete component.

Brittle materials often have microcracks, which propagate in the direction perpendicular to the crack plane under the action of tensile force. Under the pressure in this direction, the fracture will be closed to a certain extent. As a result, brittle materials are more likely to break up in the tensile state than in the compressive state, so the tensile toughness is lower than the compressive strength, and the tensile ductility is lower than the compressive ductility (Fig. 3.10). On the other hand, the modulus of compression and tensile can be equivalent, because elastic deformation does not involve crack growth. Because of its low tensile strength, brittle materials are best used in compression state, rather than in tension state. It is expected that the brittle materials with tensile stress will need to be strengthened. This is the reason why reinforced concrete (embedded reinforcement) of concrete (a brittle material) is widely used, and the reinforcement is located in the part of concrete members that encounters tension.