Usually, it should be examined when the footings are arranged for concreting i.e. reinforcement is completely engrossed but it is recommended to examine it in two phase i.e (Concrete Footings – Some Useful Footing Guidelines).
01. Initially verify formwork prior to arrange reinforcement. This is very useful because finding out & rectifying formwork defect is very difficult once the reinforcement is organized in position.
02. Checking reinforcement – Therefore, it is suggested to initially verify the formwork prior to place or tie reinforcement.
01. Centering and shuttering / Formwork:
While starting the shuttering & centering / formwork for footing , abide by the following points.
–Verify the center lines / margin from boundary etc. from reference column/bench mark pillar, boundary distance from roads and obviously orientation regarding North.
-Make sure that the foundation is laid at a designed depth according to drawing.
-Size of formwork box should be according to drawing and it should be formed with correct materials.
-The formwork should have been dry and be refined cautiously prior to use mould release agent. The similar type of release agent should have been applied through on identical formwork materials.
-The surface of formwork should have been uniform and delicately coated with mould release agent.
-The mould release agent should not be contacted with reinforcement or the solidified concrete.
-The height of shuttering must be similar with the height of pedestal and joint should have been closed to avoid any leakage of cement pulp.
-Footing box should have been supported correctly in order that the placing of footing box should be unchanged throughout concreting.
-Centre of the footing is stamped with the nail on planks or footing box.
-Foundations shuttering should be strong in dry or even rainy situations or even when ground water exist.
-Prior to tying reinforcement, get the shuttering sanctioned by Engineer-in-charge or supervisor.
-Ensure that there is no earth collection on C.C. prior to tying reinforcement.
-If foundation depth increases, make sure that the excavated earth does not slide or drop unless it is refilled. Accomplish perfect shoring and shuttering. Make sure that suitable ladder etc to enter the pit and for coming out. Besides, examine the safety of labor’s working.
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