An Airport Concrete Weijie Abnormal Cracking Reasons Analysis

Reinforced concrete structure is the most common form of structure, crack severely affecting the service life of reinforced concrete, there are many reasons that cause cracking in reinforced concrete, divided into the internal cause and external cause, internal cause is the use of materials or structures caused by the cracking, external cause is the cracking of the external loading.Sometimes is not a single factor but comprehensive role in a variety of reasons result in the crack of the structure, increased to explore the cracking reason of reinforced concrete structure and the difficulty of the repair.An airfield WeiJie separation column and the top beam joint serious craze, simple repair failed to solve the problem, through the structure detection, combined with the finite element analysis, analysis of WeiJie separation column and the top beam joints of concrete cracking causes.Cracks are analyzed based on the field test results to discuss possible causes of the numerical simulation by finite element analysis software ANSYS, the simulated WeiJie elastic state based on the temperature stress, uneven settlement stress and shrinkage stress of concrete stress state of a single condition, stress strain contours and the analysis results show that the cracking reason may be the temperature stress and shrinkage stress of concrete combination.Using SOLID65 unit to nonlinear buckling analysis of WeiJie, simulated WeiJie in temperature stress and shrinkage stress of concrete under the single and combination of cracking conditions, cracking situation in accordance with the actual situation.WeiJie is under the effect of temperature stress and shrinkage stress of concrete cracking and shrinkage of concrete stress reduced WeiJie bear the ability of tensile stress, local temperature higher than WeiJie avera ge temperature at the top of the crossbar, cause separation column cracking;After the local temperature below WeiJie average temperature at the top of the crossbar, causing the top beam crack.And according to the test and analysis results of WeiJie three p reventive measures are put forward: 1, the rules and regulations of component need to meet the minimum reinforcement ratio;2, can’t use light round bar, 4 mm in diameter according to the specification provided reinforced ribbed steel bar, at least 6 mm in diameter can improve the bond strength between concrete and reinforcing steel bar;3, need every temperature up to 20 m set expansion joints, including basic don’t disconnect;4, the WeiJie restrictions on both ends. For seeking anomaly has guiding significance to the causes of cracking in the future, for the future construction and restoration of WeiJie have guiding significance.