Investigating the structural issues caused by telecommunication towers constructed on rooftop slabs

Abstract

Rooftop installation of telecommunication towers on existing buildings has become a common strategy for expanding network coverage in dense urban areas of Sri Lanka. However, many existing structures were not originally designed to support the additional loads imposed by such installations, raising concerns regarding structural integrity and long-term durability. This study systematically investigates the structural and durability issues associated with rooftop telecommunication tower installations through field investigations across twelve sites, finite element modelling of a representative case study, and manual calculations per Eurocode standards. Field inspections revealed prevalent durability problems including water leakage, concrete spalling, and exposed reinforcement, though major structural failures were not observed. However, finite element analysis under ultimate limit state loading indicated that the host structure lacks adequate reserve capacity, with critical beams exhibiting insufficient flexural and shear reinforcement, meaning that visible condition alone is not a reliable indicator of ultimate safety. This research identifies systemic gaps in current installation practices and recommends amendments to strengthen structural verification, durability requirements, and regulatory enforcement for rooftop tower installations.