Seismic Performance Analysis Of Complex High-Rise Braced Frame Structure Of Coal Gasification Plant

Abstract

The coal gasification plant, serving as the core structure for supporting reactors, reaches nearly 100 meters in height due to the need for vertically arranged multi-stage tanks, making it significantly taller than typical chemical industry structures. Limited prior research exists on the seismic performance of such structures. This paper presents an elastic-plastic seismic analysis of a 96.5-meter-tall plant, with the lower 40 meters comprising a reinforced concrete frame with steel bracing and the upper portion using a steel frame. Under a seismic intensity of 7 degrees (0.1g), the structure sustained only minor damage to a few beams and columns, meeting Performance Objective C. For rare seismic events (0.2g), the maximum inter-story drift ratio was 1/225, allowing continued use after moderate repairs. However, the acceleration response at the top floors reached 0.48g, exceeding the 0.45g threshold, which could compromise supported equipment, suggesting a need for refined design controls over “operational functionality.” Additionally, steel bracing at the base did not reach plastic deformation before damage occurred in the concrete frame, indicating a need for improved bracing design. These findings offer valuable insights for enhancing the seismic resilience of tall structures in coal gasification plants.