Crack Distribution And Width Of The Reinforced Concrete Structure Based On Ansys Study

For Reinforced Concrete structure under the action of design load, cracking appears inevitablyin in its tensile zone.The too large crack width has influence on the safety as well as the durability of structure.So it is necessary to limit the crack width by reinforcement.In recent years,the software ANSYS has got a broad application in finite element analysis of concrete structure.The element-SOLID65,which is specially defined to analyse the concrete structure in software ANSYS,can not only display the stress and strain of structure but also show the distribution of cracks.But the calculation of crack width can not be accomplished by it.In this paper,base on the summary of research work on crack at home and abroad,the theoretical calculation formula of crack width that can be realized in ANSYS is derived and the research on distribution and width of concrete is conducted based on traditional computation theory of crack width.The research of this paper mainly includes:1. Consult a great deal of technical literature in and abroad,introduce the computation theofy of crack width with concrete structure,analysize the similarities and differences of those theoretical formula of crack width both abroad and domestic.2. As a smeared cracking model,the ANSYS cracking model can't calculate crack width.Find train of thought from traditional computation formula,derive the average crack width based on the difference of strain integration between the steel bar and concrete in crack spacing,and then get the maximum crack width theory after considering the expanded coefficient.Based on this principle,compose the formula that can calculate the crack width by APDL which is a development tool in ANSYS3. Present a numerical example of reinforced concrete simple beam,compare the crack width calculated by ANSYS with that calculated based on code and draw a conclusion that the precision of crack with calculated based on the formula derived in this article satisfies the requirement and it can be applied to the engineering practice.4. The ZQM900 Downstriker Bridging Machine was applied to execute movable frame construction of Dalong Bridge on Wenzhou-Fuzhou railway, a 32-meter simple beam.The movable frame is supported temporarily by the hollow pier.Calculate the stress of opening zone on the pier by ANSYS,derive the distribution and width of crack,finally establish the rational reinforcement.