5 Ways to Test a Concrete Structure without Destruction ( Non Destructive Tests for Concrete )

 More than a Century ago , If we have to Test a structure Against Safety , we have to Use wrecking Ball or Bulldozers to Proceed Testing , But Now a days We can do testing without destruction even without touching the Structure . Let us Talk about the Compressive Strength Test of Concrete . In the First Step ,We will Cast a Concrete Cube and then Curing is done and Compressive strength is Checked after 7, 14 and 28 days of Casting , But In Case of Existing Structures It is not Possible to do that , But Do not worry , These Days Modern Techniques are Adopted to Perform Non Destructive Test of Concrete and Now We will Discuss the Following Methods to Do the same :

• Rebound Hammer Test
• Penetration Test
• Pull Out Test
• Ultrasonic Pulse Velocity Test
• Radio Graphic Testing

1. Rebound Hammer Test

The Rebound Hammer Test is Used to Check out the Hardness of Concrete . The Spring Mechanism Inside Rebound Hammer Helps to Penetrate Hammer Head on Concrete Surface, After Releasing the Hammer Reading is Noted Down . Multiple Test Readings are Taken for Accurate Testing of Hardness of concrete . Remember that this test never give Accurate Value of Compressive Strength of Concrete . So , Only use this to Check the Hardness of Concrete .

2. Penetration Test

A Probe is Introduced into the Surface of Concrete with the Help of a Loaded Charge , Then we will measure the Depth Reached by the Probe Inside the Concrete Surface . Take Multiple Readings for a Better Result . This Test Gives Compressive Strength Measurement of Concrete .

3. Pull Out Test

The Pull Out Test of Concrete is a Kind of Semi Destructive Test of Concrete . Drilling is Performed in this Test. First of All a Steel Rod is Directly Penetrated into the Surface of Concrete and After Reaching a Depth of 3 inches It is Pulled Out and Measurement is taken according to that . This Test also Gives the Reading for Compressive Strength of Concrete .

4. Ultrasonic Pulse Velocity Test

Let us suppose that we are going to Test a wall made up of concrete . In Ultrasonic Pulse Velocity Test On the One side of Wall Pulse Generator is Kept and on other side a Pulse Receiver is Kept .During the Test Time Taken by Pulse to Reach from One end to Another is noted down. This Test is mainly carried to check whether the Section of Concrete to be Tested is a True Solid or not. If not , then it may be Possible that some Air Voids or Irregularities are Present Inside the Concrete Section. Also this test is performed to check whether Curing is done properly or not.

5. Radio Graphic Testing

In Radio Graphic Testing of Concrete section Gamma Rays are Introduced Inside the Section to Check whether :

• Reinforcement is well or not ( If Their is Any Disintegration or Not )
• Honeycomb is formed or not
• Density of RCC or PCC is Well According to Provision

But the Radio Graphic Testing of Concrete is Most Expensive Test of All the methods Discussed Above.