Engineering Surveys of Sri Lankan Schools Exposed to Tsunami

Abstract

Abstract The 2004 Indian Ocean tsunami inflicted more than 35 ,000 casualties in Sri Lanka, a third of whom were children. It affected 5% of the country’s schools, severely damaging 108 and destroying 74. The catastrophe highlighted the critical role of schools in providing educational continuity and shelter during community recovery. Sri Lanka has since rehabilitated and rebuilt most of the destroyed schools along the coastline. However, there is a limited understanding of current levels of school exposure to tsunami. This limited understanding hampers preparedness and risk reduction interventions that can improve community and educational resilience to future tsunami. This paper presents a multi-disciplinary school exposure database relevant to both vulnerability and loss modelling. The repository includes data on 38 school and 85 classroom buildings, surveyed across the coastal districts of Ampara, Batticaloa and Galle in Sri Lanka, which were heavily affected by the 2004 tsunami. A new engineering rapid visual survey tool is presented that was developed and used to conduct the physical assessment of schools for the exposure repository. School damage mechanisms observed in past tsunami inform the survey forms, which are designed to capture information at both school complex and building levels. Though validated for Sri Lanka, the tsunami survey tools can be used worldwide for the visual assessment of school exposure to tsunami. The surveys show that most Sri Lankan school buildings can be classified into three building archetypes. This means that future risk assessments can be conducted considering a small number of index buildings that are based on these archetypes with differing partition arrangements and structural health conditions. The surveys also raise three significant concerns. Firstly, that most schools affected by the 2004 tsunami remain in the same exposed locations without any consideration for tsunami design or strengthening provisions. Secondly, that Sri Lankan schools are fragile to tsunami loading and that many of the schools in the Galle district are suffering from severe corrosion, which will further affect their vulnerability to tsunami. Thirdly, that schools do not appear prepared for future tsunami and other hazards, and do not have adequate evacuation protocol in place. These observations raise the urgent need to mitigate against tsunami risk, including a holistic plan for tsunami retrofitting and for interventions to improve the tsunami preparedness of schools in Sri Lanka.