Study On Instability Characteristics And Safety Evaluation System Of High Voltage Transmission Line Tower In Goaf

In the new era,China’s economy takes off rapidly,and various basic industries and pillar industries related to the people show their vitality.The development of power industry will inevitably become the focus of people’s eyes.At the same time,the country is speeding up the deployment of base stations and supporting facilities throughout the country,and the transmission lines are almost all over the country,but we have to face some key lines passing through the coal mine goaf site.Therefore,the study on the foundation stability of transmission line tower passing through the goaf has become a top priority.Based on the engineering background of Zhangde Taoyuan I circuit π into Miao strain 220 k V line project passing through 3302 working face of Zhongtai coal mine,this paper systematically studies the instability characteristics and evaluation methods of high-voltage transmission line tower in goaf by using various research methods such as field survey and analysis,theoretical analysis,probability integral prediction,numerical simulation and fuzzy comprehensive evaluation,and obtains the following conclusions:(1)Firstly,the mechanism of surface movement and deformation of high-voltage transmission line tower in goaf is analyzed,and then the surface movement and deformation factors of J18 and J19 transmission line towers within the influence range of 3302 working face of Zhongtai coal mine are predicted and analyzed by using probability integral method.Finally,through comprehensive analysis,it is concluded that surface inclination and horizontal movement are the main factors affecting the stability of transmission line tower.(2)FLAC3D numerical simulation software is used to build the numerical simulation model according to J18,J19 transmission line tower and 3302 working face to study the foundation stability of transmission line tower under the influence of mining factors,geological factors and structural factors.It is concluded that mining factors are the main influencing factors,and geological factors and structural factors are the secondary influencing factors.Among the mining elements,the coal seam inclination and mining thickness ratio are the main influencing factors,the overlying rock lithology and geological structure are the main influencing factors,and the relative position and load size in the structure elements are the main influencing factors,and the safety range of the response index is determined.(3)The fuzzy comprehensive evaluation model of the influence degree of the stability of the high-voltage transmission line tower in the goaf site is constructed,and the grade evaluation of the stability of J18 and J19 transmission foundation within the upper influence range of Zhongtai coal mine is carried out.The results show that the stability grade of J18 tower is relatively stable,and the stability grade of J19 tower is stable.There are 117 figures,19 tables and 82references...