Design and Construction of South Asia's Tallest Tower – Lotus Tower

Priyan Mendis
Professor of Civil Engineering, Director of ARC Centre for Prefab Housing
University of Melbourne, Melbourne

The 350-meter-tall Lotus Tower, scheduled for completion in Colombo, Sri Lanka in 2018, is expected to be the tallest tower in South Asia. The design is a slender concrete tower with an antenna mast. The presentation covers its design and construction challenges, as well as novel methods used in planning and design. By providing an insight into a new numerical modeling approach to developing an evacuation strategy in high-rise buildings for occupants’ egress in emergency situations, this presentation underscores the importance of developing polycentric cities. The influence of important egress parameters, such as the crowd-flow density and evacuee demographics, were considered. The defend-in-place option was not possible, due to the concentration of people at the top levels and other constraints of the local fire authorities. The work reported in this presentation led to some layout changes in the Lotus Tower, including the relocation of the kitchen from the top of the tower, to the revolving restaurant, and then to the basement level.

The wind design was conducted using three techniques: code methods, computational fluid dynamics (CFD), and wind-tunnel tests. A comparison was made between these methods. Sophisticated CFD fluid-structure interaction techniques were used to predict accelerations and then validated with wind tunnel test results. The other challenge was a lack of reliable measured wind data in Colombo, and the wind-induced fatigue of the masts. The surmounting of those challenges is also covered in the presentation.