The purpose of this work was to establish a method of estimating impact bending capacity for brittle materials.
The test materials used in this paper were cement mortar and concrete. A pendulum type impact bending testing machine built as a trial was employed.
The main results obtained are as follows.
(1) In the region of impact speed V0≤3m/sec, the apparent kinetic energy absorbed in a specimen increases in proportion to impact energy, and this increase is nearly equal to inertial resistance of the specimen.
(2) The just breaked energy is better than the kinetic energy absorbed in a specimen as the basic value to estimate impact bending capacity, since the latter depends on impact energy but the former is not influenced by it.
(3) When the general equation on impact (eq. (1)) is applied on a similar specimen which has a constant bending span ratio, the impact resistance of the specimen is given by the form of impact energy in unit volume ΔU0/BDl. There is a close correlation between this value and the static tensile strength. This shows that impact bending fracture is more brittle.
