The Research For Non-disrepair Test To The Strength Of Long Period Concrete

The non-disrepair is the technic that using the sound, light, heat, electricity, magnetism and radial, measuring some data about concrete compressive strength, without destroying the concrete structure and influencing its workability. The technic play an important role in the aspects of ensuring the quality of the buildings and are used widely in the world.The ultrasonic-rebound method is the method that using the ultrasonic speed value and the rebound value to calculated the structure strength.A lot of reservoirs and sluices in Fujian province have been in operation for many years. Some of them have come to the fixed number of year for utilization. How to ensure they can work normally is very important. To the long period concrete strength, the relationship between the compressive strength of concrete and the data about concrete performance is changed. The existing inspecting curves of the non-disrepair only apply to the common period concrete of which has been molded below 730 days and obviously can't be applicable for long period concrete, especially for has been molded for more than ten years .In the test, the medium-type rebound instrument and the CTS-25 ultrasonic apparatus were used. According to the inspection specification of the ultrasonic-rebound method, the test was done on the accelerative carbonization cube samples to build the inspecting curve, the test was on the long period concrete structure to validate the new-building curve.By data processing, error analysis and reliability analysis, the results indicate that using the exiting curve to calculate the structure strength the error is very big and the strength is doubtful. So the Fujian province special curves using the ultrasonic-rebound method to inspect the long period commercial concrete has been purposed.