What is characteristic strength of concrete in flexure ?
Blog By Er. Navneet Kumar What is characteristic strength of concrete in flexure ? 👉Characteristic strength of concrete is the value of strength of concrete below which not more than 5 % of test results are expected to fail. It is denoted by fck. fck = fm- 1.65σ Where fm= Target mean strength & σ = standard deviation. Note- 👉Concrete is designated by characteristic cube strength of concrete at 28 days. 👉No material is truly homogeneous , so strength of similar concrete varies in different testing. 👉For most of the engineering materials ,probability is symmetrical about mean and such a curve is called Normal Probability distribution curve. ...