Which of the following statements is true regarding longitudinal reinforcement of columns?
1
The minimum number of longitudinal bars provided in column shall be four in circular columns and six in rectangular columns
2
The diameter of bars used as longitudinal bars shall not exceed 12 mm
3
The lower and upper limit of cross sectional area of longitudinal reinforcement is 0.8 and 6 % of gross cross sectional area of column
4
Spacing of longitudinal bars measured along the periphery of the column shall exceed 300 mm