Research On The Influence Of The Number Of Hyperbolic Cooling Tower Load Reduction Slots On The Collapse Effect

Blasting technology has been widely used in the demolition of buildings and structures in recent years,but it also brings many negative effects,including blasting vibration,blasting flying stones,etc.In order to reduce these negative effects,in the blasting demolition project of hyperbolic cooling tower,the blasting method of cutting the load reduction groove on the tower wall in advance by mechanical rock hammer is usually used instead of setting the blasting cut on the tower wall.This kind of demolition method,which combines machinery and blasting method,can achieve the same blasting collapse effect as setting blasting cut on the wall of cooling tower.However,the optimal number of mechanical removal of the load reduction tank has not been determined yet,so it is of great practical significance and theoretical value to analyze the impact of different number of load reduction tank on the collapse effect of hyperbolic cooling tower and determine the optimal number of load reduction tank.In this paper,based on the blasting demolition project of the cooling tower of 3 × unit in Shiliquan Power Plant,the structure and deformation characteristics of the cooling tower are analyzed theoretically,and then the blasting collapse of the cooling tower under 7 load reduction tanks is simulated numerically.The simulation results are compared with the actual project to ensure the correctness of the numerical simulation results.Finally,5-10 load reduction tanks are simulated respectively,and the numerical simulation results are compared and analyzed,and the optimal number of load reduction tanks of cooling tower is obtained.The main research results are as follows:Based on the analysis of the stress nephogram of the collapse of the hyperbolic cooling tower,and the theoretical analysis,it is considered that the hyperbolic cooling tower can not guarantee the overall rigidity during the collapse process,and the distortion and tearing deformation of the tower wall will occur.As the collapse continues,the large cracks on the tower wall will develop into the plastic deformation with the characteristics of the torsion and folding depression of the tower wall;the collapse will be numerical value combined with the engineering example Simulation,under the condition of ensuring that all data of the model are identical with the actual situation,the process of collapse is completely consistent with the actual collapse video,and the correctness of the numerical simulation is obtained,which provides the basis for the comparative simulation of the collapse results of different numbers of load reduction tanks;6 different numbers of cooling tower load reduction tanks corresponding to the collapse and fragmentation degree of the explosion pile,5 and 10 load reduction tanks are compared The corresponding fragmentation degree of blasting pile is relatively low,there is not completely broken concrete,and the number of remaining load reduction tanks corresponds to the relatively good fragmentation degree;by comparing the collapse range of six different number of cooling tower load reduction tanks,it is concluded that the more the number of load reduction tanks is,the better the fragmentation effect is,the smaller the collapse range of blasting pile is;by comparing the corresponding six different number of cooling tower load reduction tanks It is concluded that the collapse speed of tower wall does not mean that the more the number of load reduction slots is,the faster the collapse speed is;through the comparison of various evaluation indexes of blasting effect,it is concluded that the optimal number of load reduction slots is 6 or 7,which is completely consistent with the actual number of load reduction slots in blasting engineering.This paper simulates the selection of the number of load reduction slots in the actual blasting demolition of cooling tower in the future It has certain reference value.