Effects of Subsoil Characteristics on the Earthquake Loading of Steel Lattice Telecommunication Towers in the South Asia

Self-supporting lattice towers, which are having quite a few unique structural features, play a vital role in communication networks. Ensuring structural stability of these giant structures under all possible natural and human threats are vital as failures of such structures may cause a catastrophic human & property damages. Further, possible communication outages caused by failure of tower/towers in disaster situation are a critical as it may hamper rescue and other emergency operations. This was experienced by South and South East Asian countries during 2004 Tsunami. Hence, need of mitigating these situations have been highlighted by various reports. Therefore, ensuring structural integrity of self-supporting lattice towers under seismic forces is an essential and timely need. This paper discusses a seismic performance of four leg and three leg lattice towers under Response Spectrum analysis under different sub soil conditions. Results of seismic analyseshas also been compared with wind analyses results.