Applicability regulation method for cement-based materials

A method for evaluating penetration resistance of a cement-based material against non-rigid projectiles, comprising:

• S1:
• considering a cement-based material as a multiphase material, respectively measuring a Rockwell hardness of each phase, and calculating an equivalent length of each phase based on a volume ratio of each phase;
• S2:
• determining an effective hardness of the cement-based material through weighted calculation based on the Rockwell hardness of each phase and the equivalent length of each phase;
• S3:
• preparing a non-rigid projectile using a single-phase material as a parent material, and measuring a Rockwell hardness of the parent material as an effective hardness of the non-rigid projectile;
• S4:
• calculating a ratio of the effective hardness of the non-rigid projectile to the effective hardness of the cement-based material to obtain relative hardness;
• and
• S5:
• measuring penetration resistance and a projectile deformation degree for various cement-based material and non-rigid projectile combinations with different relative hardness, and respectively establishing association relationships between the penetration resistance and the relative hardness as well as between the projectile deformation degree and the relative hardness, wherein:
• in S5, the penetration resistance comprises normalized penetration depth and crater diameter;
• a relationship between the normalized penetration depth Ypenetration depth and the relative hardness REH is:
• Y
• crater
• ⁢
• diameter
• =
• 74.56
• -
• 1
• ⁢
• 9
• ⁢
• 8
• ⁢
• 9
• ⁢
• 3
• .
• 5
• ⁢
• 0
• ⁢
• 5
• 1
• +
• (
• REH
• 0
• .
• 1
• ⁢
• 2
• ⁢
• 0
• )
• 0
• .
• 1
• ⁢
• 2
• ⁢
• 0
• ;
• a relationship between the crater diameter Ycrater diameter and the relative hardness REH is:
• Y
• crater
• ⁢
• diameter
• =
• 74.56
• -
• 1
• ⁢
• 9
• ⁢
• 8
• ⁢
• 9
• ⁢
• 3
• .
• 5
• ⁢
• 0
• ⁢
• 5
• 1
• +
• (
• REH
• 0
• .
• 1
• ⁢
• 2
• ⁢
• 0
• )
• 0
• .
• 1
• ⁢
• 2
• ⁢
• 0
• ;
• in S5, the projectile deformation degree comprises normalized projectile length change, normalized projectile diameter change, and normalized projectile mass change;
• a relationship between the normalized projectile mass change γm and the relative hardness REH is:
• γ
• m
• =
• 1
• .
• 2
• ⁢
• 2
• ⁢
• 9
• +
• 2
• ⁢
• 2
• ⁢
• 8
• ⁢
• 5
• ⁢
• 9
• .
• 6
• ⁢
• 9
• ⁢
• 1
• 1
• +
• (
• REH
• 0
• .
• 3
• ⁢
• 6
• ⁢
• 1
• )
• 9
• .
• 3
• ⁢
• 0
• ⁢
• 7
• ;
• a relationship between the normalized projectile length change γl and the relative hardness REH is:
• γ
• l
• =
• 2
• ⁢
• 0
• .
• 1
• ⁢
• 9
• ⁢
• 7
• -
• 2
• ⁢
• 1
• ⁢
• 7
• .
• 6
• 1
• +
• (
• REH
• 0
• .
• 9
• ⁢
• 4
• ⁢
• 7
• )
• 8
• .
• 5
• ⁢
• 4
• ⁢
• 4
• ;
• a relationship between the normalized projectile diameter change γd and the relative hardness REH is:
• γ
• d
• =
• 1
• ⁢
• 3
• .
• 0
• ⁢
• 1
• ⁢
• 8
• +
• 6
• ⁢
• 2
• ⁢
• 1
• ⁢
• 8
• .
• 9
• ⁢
• 4
• ⁢
• 1
• 1
• +
• (
• REH
• 0
• .
• 6
• ⁢
• 1
• ⁢
• 2
• )
• 6
• .
• 5
• ⁢
• 4
• ⁢
• 7
• .