Study on the method of concrete strength testing on the construction site

In order to study the correction coefficient of concrete compressive strength with small core specimen on the construction site,young concrete plate and old reinforced concrete beam are used to conduct the testing.By drilling the Φ100 mm,Φ75 mm,Φ50 mm core specimens,through ultrasonic rebound method,and drilling core experiement,the relationship of compressive strength between various core concrete specimens and standard cube concrete are obtained.And thus the correction formula of concrete compressive strength with small core specimen is deduced.The result can be reference for testing concrete compressive strength on the construction site.