Cracking Of Reinforced Concrete Structures And Engineering Applications

To a certain degree and in different shapes, the structure of concretewill produce cracks in the process of the construction and its usage. Itmust be pointed out that the interior reinforcing steel bar will be usuallycorrupted; the carrying capacity, the durability, the impermeability of RCmembers will be reduced, when the cracks come to a extent, therefore,they will impact on the appearance of the buildings and their life-span.Worst of all, they will threaten the safety of the construction. So thedifficult problem of cracks in concrete is a technical one, which hastroubled technicians for decades. The chief aim of this paper is to analyzethe reasons of cracks from materials, design and construction controlling.It also explores how to prevent them and how to improve the engineeringmeasures of concrete permeability. On these bases, we come up with aneffective reinforcing means and the reliability assessment of concretecracks. The contents are as followings:1. This paper has analyzed and summarized the reasons of formingcracks of AC members, the influence on the carrying capacity anddurability; the way of testing and the pattern of numerical value, theremedy and management of concrete cracks;2. It presents calculating ways and means of largest width of cracksby using the finitude meta model and code. It compares and analyzes thecalculating results, and puts forward an effective way of reducing thewidth by means of adopting difference designing criterion of concretestructure to a brief branch girder of AC, including Code for design ofconcrete structures (GB50010-2002), Code for design of highwayreinforced concrete and prestressed concrete bridges and culverts (JTG D62-2004), Code for design on reinforced concrete structure of railwaybridge and culvert (TB 10002.3-2005), Design code for hydraulic concretestructures(DL/T5057-1996).3. It also analyzes the cracks reason of the workshop's housecrossbeam of Zhe Xi Water and Electricity Station, an engineering project,exerting fundamental principles and methods of the reliabilityassessment in the concrete component. The sample indicated that most ofcomponents could not meet the needs of criterion. They need repairingand reinforcing.4. Aiming at the situation in the workshop of Zhe Xi Water andElectricity Station, it presents three projects. That is high strength steel,reinforcing prestress and rebuilding net frame of the whole house. Incomparison with the other two projects, in the long run, the cost ofrebuilding net frame of the house is low; and it is easy to control theconstruction techniques, and it will receive a good results, though it willcost much in the short run. Finally, the project of rebuilding net frame ofthe house is chosen by a series of comprehensive analysis andcomparison with construction interfere, construction techniques andcomparing investment.