Research On The Repair Technology For Partial Defects Of Concrete By Replacement Method

In practice of engineering, the concrete structure reinforcement methods of increasing section reinforcement method, concrete displacement reinforcement method, externally bonded steel frame reinforcement method, paste fiber composite reinforcement method, plus an additional prestress reinforcement method and multi-point supporting reinforcement method are frequently used. The concrete displacement method is generally used in situation where the compression area of bearing members’ concrete is of low strength or the concrete members’ local concrete is of great defects. This kind of method can reject the low-intensity and defective concrete of the compression area of existing members, it also can pour a new higher grade concrete, letting the bearing capacity of existing members get recovered or enhanced. For the replaced reinforcement of the low compressive strength concrete, entire replacement of members or local replacement preserving the core column can be used, these kinds of methods are tested in many practical cases, mature technologies can be referred to.When reinforcing the low-intensity and defective concrete of the compression area of bearing members, weather the replacing area, boundary form and replacement depth affect and how these factors work on the bearing capacity, fracture development and failure mode of different members after replacement shall be considered. The current strengthening codes only indicate the construction requirements, the effect of above-mentioned factors are not taken into account. Workers in projects also inclined to judge by experience, few to discuss or analyze about this aspect.This paper studied the situation when reinforcing the vertical concrete members, how different replacing area, boundary form and replacement depth affect the members’ failure mode, ultimate bearing capacity and fracture development, if they do affect. This paper puts forward specific steps of experiment, including key points like construction process, member installing and test loading, etc.In the end, this paper summed up questions and achievements throughout the experiment, proposed corresponding advice and hypothesis aimed at followed-up research.