Shrinkage Cracking And Fatigue Properties Of New-To-Old Concrete Interface

With the wide development of repairing engineering, we meet a problem that structures have not enough durability after repaired. With a large number of bridges and pavements in urgent need of repair, simple, successful, and durable repair methods are needed. The thesis analyses primary factors which affect the durability of repaired structure and point out the shortcomings of the existing repairing methods. In the first the thesis offers a economical durable repairing method, which uses carbon fiber reinforced mortar between the new-to-old concrete as a transition. At first, through selecting materials and mixing procedures, we develop a technics that can make high quality carbon fiber reinforced mortar. Beams and slabs are repaired by new and traditional method. Comparing the two methods through observing shrink cracks of new concrete and fatigue test, we get the results that show the new method can effectively improve durability of repaired structure. The repairing method has high value at science and engineering.