The Stress State Analysis Of Xiao Lang Di Prestressed Concrete Lining Structure

Annular-anchoring unbonded prestressed concrete lining structure is borne theload of gravity,prestressing force, temperature variation, high pressure water inconstruction period and operating period, its stress state is very complex under thevarious kinds of working conditions. How to adopt effective measures to analyze andsimulate its stress state is a very hard nut to crack. As a new-type structural style, onlyby comprehensive and deepgoing analysis can find out the law of how workingconditions influence the stress state, and provide favorable reference for the similarstructures in the future. In the study departed, there is already a lot of research resultsabout the stress state of construction stretch-draw period of unbonded prestressedconcrete lining structure. But the research result about stress state under temperaturevariation and waterhead variation is still few. Contraposing the issues above, based onthe measured data of Xiaolangdi, regression analysis method is adopted to analyze thestress state of lining structure under temperature variation, single factor variablemethod is also adopted to analyze the stress state of lining structure under waterheadvariation. Meanwhile, based on ANSYS finite element program, the stress state oflining structure under temperature variation in construction period and the stress stateof lining structure under waterhead variation in operating period deeply studied.The results show that when the temperature difference between inner side andoutside of lining tunnel is negative, the pressure stress of inner side will decrease, itwill be disadvantageous to the stress state of inner side; And when the temperaturedifference between inner side and outside is positive value, it will improve the stressstate of inner side. With the increase of water level, the annular compressive stresswill decrease, namely, the increase of waterhead will result in the decrease of annularcompressive stress of pre-stressed anchor cable. But, whatever the maximumtemperature difference or the maximum waterhead, Xiaolangdi lining structure isunder safe operation without exception.