The cross-sectional area of longitudinal reinforcement, shall be not less than 0.8 percent nor more than 6 percent of the gross cross- sectional area of the column. NOTE - The use of 6 percent reinforcement may involve practical difficulties in placing and compacting of concrete; hence lower percentage is recommended. Where bars from the columns below have to be lapped with those in the column under consideration, the percentage of steel shall usually not exceed 4 percent. Save This ❤️🏗️ ______

Development Length Explained Development Length (Ld): It is the extra length of reinforcement bar provided beyond the point of maximum stress so that the bar can transfer its full stress into the concrete by bond. 🔹 Why it is needed? To prevent slippage of bars from concrete. Ensures safe transfer of stresses between steel and concrete. Provides anchorage and avoids sudden failures. 🔹 Formula: L_d = frac{0.87 f_y , phi}{4 tau_{bd}} Where: = Yield strength of steel (N/mm²) = Diameter of bar (mm