Structural Survey of the Schools Affected by Tsunami and Earthquake in Aceh Province and Nias Indonesia
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STRUCTURAL SURVEY OF THE SCHOOLS AFFECTED BY TSUNAMI AND EARTHQUAKE IN ACEH PROVINCE AND NIAS INDONESIA - FINAL REPORT - March 2005 – February 2006 Final Report on Structural Survey of Schools: March 2005 - February 2006 TABLE OF CONTENT: Page 1. INTRODUCTION……………………………………………………….……. 3 2. OBJECTIVES AND EXPECTED OUTPUTS OF SCHOOLS SURVEY……………………………………………………………….…….. 3 2.1. METHODOLOGY OF WORKS………………………………..…….. 3 3. ACHIEVED OUTPUTS OF SCHOOLS SURVEY………………….…......... 4 4. OBSERVATIONS ON TECHNICAL ISSUES………………………….….... 5 4.1. EXISTING SCHOOLS (STANDARDS APPLIED)………………….... 5 4.2. STRUCTURAL TYPES OF THE BUILDINGS………………........….. 6 4.3. STRUCTURAL DAMAGES ON SCHOOL BUILDINGS……………. 7 4.4. COMMON STRUCTURAL DEFICIENCIES CONTRIBUTING MOST DAMAGES..…………………..……….….. 9 4.4.1. REINFORCEMENT RELATED DEFICIENCIES……………………. 9 4.4.2. CONCRETE RELATED DEFICIENCIES…………………..………… 10 4.4.3. WOODEN STRUCTURES DEFICIENCIES………………………….. 10 4.4.4. STRUCTURAL DETAILING DEFICIENCIES……………………..… 11 4.5. RECOMMENDATIONS FOR RETROFITTING……………………… 12 4.5.1. REPAIR OF CRACKS…………………………………………………. 12 4.5.2. FIXING THE CROSS WALLS TO LONG WALLS……………….….. 12 4.5.3. REBUILDING OF DAMAGED PART OF THE WALL……………… 13 4.5.4. REPAIR OF DAMAGED RING BEAMS JUNCTIONS…………….… 13 4.5.5. REPAIR OF DAMAGED CONCRETE COLUMNS……………......… 13 4.5.6. REPAIR OF DAMAGED WOODEN SEGMENTS..…………………. 14 4.6. RECOMMENDATIONS FOR CONSTRUCTION OF NEW SCHOOLS………………………………………………...…. 15 4.6.1. NEW CONSTRUCTION STANDARDS…………………………….... 15 4.6.2. PRACTICAL IMPROVEMENT OF STRUCTURAL SEGMENTS..… 16 4.6.3. RECOMMENDATIONS FOR PRE-CONSTRUCTION PHASE.…..… 17 4.6.4. RECOMMENDATIONS FOR CONSTRUCTION PHASE.………..… 17 4.6.4.1. SUPERVISION OF WORKS………………………………………... 17 4.6.4.2. MATERIALS AND WORKMASHIP……………………………….. 17 4.6.4.3. CERTIFICATION AND TESTING OF MATERIALS……………… 18 5. CONCLUSION…………………………………………………………...….. 19 5.1. LESSONS FROM RECENT DESTRUCTION……………………….. 19 6. ANNEXES…………………………………………………………………… 20 ANNEX 1: BUILDING STANDARDS FOR SEISMIC ZONES 4,5,6…...... 21 ANNEX 2: PHOTOS OF TYPICAL DAMAGES ON SCHOOLS……...…. 25 ANNEX 3: PHOTOS OF TYPICAL DEFICIENCIES ON SCHOOLS…..... 31 ANNEX 4: LIST OF SURVEYED SCHOOLS BY DISTRICTS………....... 34 Bojan Stajic UNOPS Construction Engineer Page: 2 Lamia Maglic UNOPS Construction Engineer Final Report on Structural Survey of Schools: March 2005 - February 2006 1. INTRODUCTION Earthquake and Tsunami that hit Aceh province in December 26th 2004 but also earthquake that hit Nias in March 28th 2005, caused unprecedented devastation of housing, social and communal infrastructure and huge human casualties. Hundreds of schools throughout Aceh Province and Nias were damaged or destroyed. Ministry of National Education (MoNE, figures from June 2005) estimates that 2.269 schools out of total 5.565 in Aceh Province were damaged. 309 SDN and MIN primary schools suffered light damages, further 494 were heavyly damaged, 235 were totally destroyed. In Nias heavy damages were reported on 413 SDN and MIN schools. The learning capacities were severely reduced, remaining learning facilities endangered. Together with material damages, there were huge casualties both among students and teachers. In new situation, approximately 177.000 students needed learning facilities. About 400.000 persons had to move to other locations as Internally Displaced Persons. In order to continue lectures, in many remaining schools classes were regrouped, more classes attended lessons in one class room etc. In order to plan and coordinate necessary actions towards ensuring safety for students in remaining schools, there was urgent need to survey all schools and provide figures about real state of facilities in new situation. Remaining schools had to be surveyed in order to identify potentially unsafe ones and determine those to be rehabilitated or reconstructed in order to enable continuation of education process. All figures necessary to plan further actions on provision of safe school spaces had to be compiled in short time. In co-ordination with Department of Education, short after disaster, UNICEF started the structural survey of the schools in Aceh Province through cooperation with UNOPS, whose team of structural engineers commenced survey in late March 2005. 2. OBJECTIVES AND EXPECTED OUTPUTS OF SCHOOLS SURVEY 2.1. METHODOLOGY OF WORK • Field visit of schools • Visual observation with recording of photos • Detection of damages • Analysis of cause of damages • Assessment of safety condition in every class room and other school rooms • Warning of schools authorities on site in case of unsafe rooms • Recommending of necessary actions: rehabilitation/reconstruction • Reporting to UNICEF/UNOPS on survey findings: unsafe rooms and recommended activities Many schools had already been surveyed by DoE, NGOs or other state institutions teams, however compiled reports about structural conditions and level of damage on these schools were confusing and not reliable and had to be checked again. Targeted category of schools to be surveyed were all SDN and MIN schools in use. Priority was to identify unsafe schools or rooms within the schools and to issue warning through UNICEF to school authorities and Department of Education. In case of condemning the schools, after approval by DoE, Bojan Stajic UNOPS Construction Engineer Page: 3 Lamia Maglic UNOPS Construction Engineer Final Report on Structural Survey of Schools: March 2005 - February 2006 students would be evacuated from unsafe school and the temporary schools (in the beginning tents, later prefabricated buildings) would be erected to enable continuation of lectures out of unsafe buildings until new permanent school is completed. Since the most affected areas by Tsunami and earthquakes were Banda Aceh, Aceh Barat, Aceh Besar, Aceh Jaya, Nagan Raja, Pidie and Nias, survey of the schools was focused on these districts. Together with structural survey of the schools aiming to identify unsafe learning spaces and those for rehabilitation or new construction, the intention was also to provide accurate findings about construction failures contributing severe damages. These findings would enable to determine corrective measures in rehabilitation and reconstruction of damaged schools also learn about failures in previous construction practices allowing destruction of the schools and which improvements are needed for construction of new ones. Beside schools damaged by Tsunami, also those deep inland, damaged by earthquake were to be surveyed. 3. ACHIEVED OUTPUTS OF SCHOOLS SURVEY From March 2005 till February 2006, UNOPS Structural Engineers surveyed 428 schools. The structural survey of the schools was performed in districts Banda Aceh, Aceh Barat, Aceh Besar, Aceh Jaya, Nagan Raja, Pidie, Nias and Nias Selatan.These districts were the most affected and survey of the schools was focused on them. Together with SDN and MIN that were targeted category, 51 SMAN, SMPS and SMPN schools were surveyed. Out of 428 surveyed schools, 212 schools were found to need rehabilitation, 154 to need reconstruction, 56 to need both rehabilitation and reconstruction (schools with more buildings of different level of damages), only 6 schools needed no activity. These figures are presented in following table: District Banda Aceh Aceh Aceh Nagan Nias Pidie Aceh Besar Barat Jaya Raya and Nias Selatan Surveyed 107 136 53 21 22 80 9 schools Rehabilitation 69 90 22 6 12 9 4 Reconstruction 31 29 24 12 5 51 2 Rehabilitation/ 7 11 7 3 5 20 3 Reconstruction No activity 0 6 0 0 0 0 0 Together with determining of activities that need to be undertaken, the safety conditions were inspected on each school. The schools were declared as UNSAFE, PARTS UNSAFE, GOOD, * GOOD, PARTS DESTROYED, DESTROYED, depending on scale and type of destruction and estimate that some class rooms or entire school can collapse. Out of total of 428 surveyed schools, 25 were declared as UNSAFE, meaning that classes were still ongoing in entirely unsafe buildings (close to collapse) in the time of structural survey. In such cases Bojan Stajic UNOPS Construction Engineer Page: 4 Lamia Maglic UNOPS Construction Engineer Final Report on Structural Survey of Schools: March 2005 - February 2006 the school authorities were warned immediately on site, Department of Education through UNICEF. This and other safety categories are presented in “Lists of surveyed schools by Districts”, given in ANNEX 4 of this report. Exact lists of the schools to be surveyed were composed in co-operation between UNICEF and Government (Department of Education and BRR). The survey performed was of “quick assessment” type, meaning visual inspection of the schools, with identification and defining the level of damage on site. Following intention to improve the general condition of schools where needed, besides structural safety of them, also other non-structural items (conditions of toilets, sanitation and water supply, capacities of teachers accommodation-houses in remote schools, roofs, eaves and ceilings conditions etc.) were inspected and findings included in reports. For each surveyed school, the numbers of photos were taken for reports and files. The findings of all 428 surveyed schools were presented in 24 reports, submitted to UNICEF. The list of surveyed schools with findings and recommendations is given in Annex to this report. ANNEX 1 to this report is matrix with new construction standards, ANNEX 2 is photo presentation of most common structural damages on schools, ANNEX 3 is photo presentation of most common deficiencies in construction, which