Current Science

Open Access Open Access  Restricted Access Subscription Access

Failure analysis of transmission line tower subjected to combined wind and dust loads


Affiliations
1 Department of Civil Engineering, Gayatri Vidya Parishad College of Engineering (Autonomous), Madhurawada, Visakhapatnam 530 048, India
2 CSIR-Structural Engineering Research Centre, Chennai 600 113, India
 Untitled  

Towers play a vital role in the transmission line (TL) system. The main objective of the present study is to analyse the failure of towers subjected to dust storms. This study, analyses the failure of a 765 kV single-circuit delta-type horizontal configuration tower in the river delta region near Agra. TL towers are designed based on IS 802 Part 1/Sec 1 and 2 standards. Dust particles of soil may be lighter individually, but have definite density. The wind carrying dust particles may increase the wind pressure on the tower line system. The increased wind pressure significantly affects the sag and tension of ground wire and conductor and results in additional loads on the tower, thus causing failure. It also increases wind load on the tower body and insulator string. There is literature related to numerical and wind tunnel studies on the combined effect of wind and rain loads, but no information is available on the wind and dust loads at present. The density variation method is used in the present study for calculation of additional wind pressure due to dust particles during storms. A relation between density of air mix, volume fraction of dust and density of dust particles is considered. Using FEM software, the tower is analysed for existing design loads and verified for its strength adequacy. The tower stability is studied by analysing for additional loads considering the presence of dust particles in the wind for three different volume fractions of 0.01%/m3, 0.02%/m3 and 0.03%/m3. The wind pressure increases by about 10% for an in-crease of every 0.01% of dust particles in the wind. The tension in the conductor and ground wire increases by 8%. The existing tower design is inadequate to withstand the additional forces from wind storms associated even with a small fraction of dust particles and may be the reason for the failure of towers in northern India during a particular period of the year.

Keywords

Dust storms, failure analysis, power supply, transmission line towers.
User
Notifications
Font Size

  • Fu, X. and Li, H. N., Dynamic analysis of transmission tower-line system subjected to wind and rain loads. J. Wind Eng. Ind. Aerodyn., 2016, 157, 95–103.

  • Kikuchi, N., Matsuzaki, Y., Yukino, T. and Ishida, H., Aerodynamic drag of new-design electric power wire in a heavy rainfall and wind. J. Wind Eng. Ind. Aerodyn., 2003, 91(1), 41–51.

  • An, L., Wu, J., Zhang, Z. and Zhang, R., Failure analysis of a lattice transmission tower collapse due to the super typhoon Rammasun in July 2014 in Hainan Province, China. J. Wind Eng. Ind. Aerodyn., 2018, 182, 295–307.

  • Zhang, J. and Xie, Q., Failure analysis of transmission tower subjected to strong wind load. J. Constr. Steel Res., 2019, 160, 271– 279.

  • Mahmoud, G. H., Tork, B. S. and El-Beshlawy, S. A., Structural capacity and failure mechanisms of transmission towers under high intensity wind loading. IOSR J. Mech. Civ. Eng., 2016, 13(5), 25–33.

  • Fu, X., Wang, J., Li, H. N., Li, J. X. and Yang, L. D., Full-scale test and its numerical simulation of a transmission tower under extreme wind loads. J. Wind Eng. Ind. Aerodyn., 2019, 190, 119–133.

  • Fu, X., Li, H. N. and Wang, J., Failure analysis of a transmission tower subjected to combined wind and rainfall excitations. Struct. Design Tall Spec. Build., 2019, 28(10), 1–19; doi.org/10.1002/ tall.1615.

  • Fu, X. and Li, H. N., Theoretical and experimental studies of the rain load for transmission tower based on single-raindrop impinging force. Int. J. Struct. Stability Dyn., 2019, 19(11), 1950133.

  • Tian, L., Pan, H., Qiu, C., Ma, R. and Yu, Q., Wind-induced collapse analysis of long-span transmission tower-line system considering the member buckling effect. Adv. Struct. Eng., 2019, 22(1), 30–41.

  • Li, J. X., Li, H. N. and Fu, X., Dynamic behaviour of transmission tower-line systems subjected to insulator breakage. Int. J. Struct. Stability Dyn., 2018, 18(3), 1–24.

  • Tian, L., Guo, L., Ma, R., Gai, X. and Wang, W., Full-scale tests and numerical simulations of failure mechanism of power transmission towers. Int. J. Struct. Stability Dyn., 2018, 18(9), 20.

  • Wang, F. Y., Xu, Y. L. and Qu, W. L., Multi-scale failure analysis of transmission towers under downburst loading. Int. J. Struct. Stability Dyn., 2018, 18(2), 1850029.

  • Tapia-Hernández, E., Ibarra-González, S. and De-León-Escobedo, D., Collapse mechanisms of power towers under wind loading. Struct. Infrastruct. Eng., 2017, 13(6), 766–782.

  • Fu, X., Li, H. N. and Li, G., Fragility analysis and estimation of collapse status for transmission tower subjected to wind and rain loads. Struct. Saf., 2016, 58, 1–10.

  • Yang, S. C. and Hong, H. P., Nonlinear inelastic responses of transmission tower-line system under down burst wind. Eng. Struct., 2016, 123, 490–500.

  • Asgarian, B., Eslamlou, S. D., Zaghi, A. E. and Mehr, M., Progressive collapse analysis of power transmission towers. J. Construct. Steel Res., 2016, 123, 31–40.

  • Yang, Q., Xiong, X. F., Wei, Y. N., Wang, J. and Weng, S., Shortterm reliability evaluation of transmission system under strong wind and rain. J. Power Energ. Eng., 2014, 2, 665–672.

  • Li, H. N., Tang, S. Y. and Yi, T. H., Wind-rain-induced vibration test and analytical method of high-voltage transmission tower. Struct. Eng. Mech.: Int. J., 2013, 48(4), 435–453.

  • Xie, Q. and Sun, L., Failure mechanism and retrofitting strategy of transmission tower structures under ice load. J. Constr. Steel Res., 2012, 74, 26–36.

  • IS 875 (Part 3), Indian standard code of practice for design loads (other than earthquake) for buildings and structures, Part 3: wind loads, Bureau of Indian Standards (BIS), New Delhi, 2015.

  • IS 802 (Part 1/Sec 1), Indian standard code of practice for use of structural steel in overhead transmission line towers, Part 1: materials, loads and design strengths, Section 1: materials and loads,

  • BIS, New Delhi, 2015.

  • IS 802 (Part 1/Sec 2), Indian standard code of practice for use of structural steel in overhead transmission line towers, Part 1: materials, loads and design strengths, Section 2: design strengths, BIS, New Delhi, 2016.

  • ASCE/SEI 10–15, Design of latticed steel transmission structures, American Society of Civil Engineers.


Abstract Views: 340

PDF Views: 172 PDF Views: 137




  • Failure analysis of transmission line tower subjected to combined wind and dust loads

Abstract Views: 340  |  PDF Views: 172 PDF Views: 137

Authors

Shaik Esub Salaam
Department of Civil Engineering, Gayatri Vidya Parishad College of Engineering (Autonomous), Madhurawada, Visakhapatnam 530 048, India
N. Prasad Rao
CSIR-Structural Engineering Research Centre, Chennai 600 113, India
P. Krishnam Raju
Department of Civil Engineering, Gayatri Vidya Parishad College of Engineering (Autonomous), Madhurawada, Visakhapatnam 530 048, India

Abstract


Towers play a vital role in the transmission line (TL) system. The main objective of the present study is to analyse the failure of towers subjected to dust storms. This study, analyses the failure of a 765 kV single-circuit delta-type horizontal configuration tower in the river delta region near Agra. TL towers are designed based on IS 802 Part 1/Sec 1 and 2 standards. Dust particles of soil may be lighter individually, but have definite density. The wind carrying dust particles may increase the wind pressure on the tower line system. The increased wind pressure significantly affects the sag and tension of ground wire and conductor and results in additional loads on the tower, thus causing failure. It also increases wind load on the tower body and insulator string. There is literature related to numerical and wind tunnel studies on the combined effect of wind and rain loads, but no information is available on the wind and dust loads at present. The density variation method is used in the present study for calculation of additional wind pressure due to dust particles during storms. A relation between density of air mix, volume fraction of dust and density of dust particles is considered. Using FEM software, the tower is analysed for existing design loads and verified for its strength adequacy. The tower stability is studied by analysing for additional loads considering the presence of dust particles in the wind for three different volume fractions of 0.01%/m3, 0.02%/m3 and 0.03%/m3. The wind pressure increases by about 10% for an in-crease of every 0.01% of dust particles in the wind. The tension in the conductor and ground wire increases by 8%. The existing tower design is inadequate to withstand the additional forces from wind storms associated even with a small fraction of dust particles and may be the reason for the failure of towers in northern India during a particular period of the year.

Keywords


Dust storms, failure analysis, power supply, transmission line towers.

References





DOI: https://doi.org/10.18520/cs%2Fv121%2Fi4%2F511-520