Behavior of single pylon of air cooled condenser support structure under seismic and wind forces

Abstract

Air cooled condenser (ACC) is the setup of machinery and motors, which is used in thermal power plant to condensate hot steam coming out from turbine. It is an approach to reduce the cooling water demand using direct dry cooling phenomena, which requires no consumptive water and also reduces a power plant water demand by up to 90%. The ACC support structure consists of wind wall at top, truss frames, columns, and bottom raft, respectively. A typical ACC support structure can be of any height depending upon wind and topographic conditions, which is subjected to concentrated load so generally it acts like an inverse pendulum. Due to high sensitivity of this type of structures toward lateral and dynamic loads, it requires meticulous engineering analysis and deliberate sectional design which is optimized too. This paper presents the detailed optimized design criteria for a 6 × 8 fan air cooled condensers using design moments and axial force from seismic analysis (response spectrum method) and wind load analysis (gust effectiveness factor method) using IS 875:2002 (Part-3). Both analyses are done on a single pylon to find out the governing load using STAADPro.