Research on Deterioration of Mechanical Properties of Tunnel Lining Structure under Reinforcement Corrosion
Considering the factors caused by corrosion such as deterioration of mechanical properties of reinforcement,reduction of effective section of concrete and degradation of bonding properties,a model of reinforcement corrosion tunnel lining under the action of surrounding rock pressure was established.The changes of deformation,damage,internal force and crack width of the lining structure under different corrosion rates were analyzed.The results show that:The order of severity of the lining structure by corrosion is as follows:arch crown＞spandrel＞arch abutment＞hance＞inverted arch.Corrosion causes the redistribution of internal forces in the structure.When the corrosion rate develops from 0％to 20％,the bending moment of the tension part on the inner side of the lining structure gradually decreases,while the bending moment of the tension part on the outer side of the lining structure gradually increases.There is little change in the axial force,with the maximum change in axial force at only 7.53％.The crack width of arch crown develops the fastest,fol-lowed by the spandrel and arch abutment.The maximum crack width at the arch crown already does not meet the dura-bility requirements when the corrosion rate develops to 2.7％.The influence of corrosion of the reinforcement in the cracked area plays a dominant role in the deterioration of the mechanical properties of the lining.In the case of corrosion only in the cracked area,the low of the lining structure mechanical properties deterioration is similar to that of full-length corrosion of reinforcement.However,the result shows the decreasing of magnitude of internal force change and crack width due to corrosion.
secondary liningconcrete damagecorrosioninternal force redistributioncrack width
万方数据
维普
