A Report on Post-Earthquake Rapid Visual Damage Assessment of Buildings Of Tribhuvan International Airport

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1 A Report on Post-Earthquake Rapid Visual Damage Assessment of Buildings Of Tribhuvan International Airport Prepared By: Civil Engineering Division Tribhuvan International Airport Civil Aviation Office Gauchar, Kathmandu 7 th May,

2 Report on Post-Earthquake Rapid Visual Assessment of Buildings and other Damages at TIA Background The 7.9 magnitude earthquake occurred on 25 th April 2015 at 11:56 a.m. NST, with its epicenter approximately 34 km east-southeast of Lamjung, Nepal. The tremor was caused by a sudden thrust, or release of built-up stress, along the major fault line where the Indian Plate, carrying India, is slowly diving underneath the Eurasian Plate, carrying much of Europe and Asia. Kathmandu, situated on a block of crust approximately 120 km (75 miles) wide and 60 km (37 miles) long, reportedly shifted 3 m (10 ft) to the south in just 30 seconds. The devastating earthquake created heavy damages to infrastructures and took away thousands of lives throughout the country. About 14 district were badly affected by this earthquake and more than 8000 people are reported to have lost their lives so far with death tools likely to increase. Introduction The devastating quake causes huge damage on different infrastructures. It is essential to carry out quick evaluation of damage and provide as soon as possible effective recovery after the impact. Visual Damage Assessment of the TIA office buildings was carried out to assess the damage and safety measures needed immediately. This report is prepared based on visual assessment by technical team of Civil Engineering Division, TIA.The assessment included a brief visual inspection of structures to identify the presence or absence of thedamage. The inspection primarily includes; Collapse, partial collapse of building. Building or story leaning / out of plumb Ground movement or slope failure, scour, erosion Damage to primary structural members, racking of walls Damaged services (electric / water supply/ sanitation) Proximity of other nearby risks Runway / taxiway damages 2

3 SUMMARY: Teams from Civil Engineering Division were assessed to detect the damage caused by devastating earthquake. In our reconnaissance survey civil engineers team from TIA conducted a visual survey of the international terminal, old domestic terminal, operation airlines building, new domestic terminal, cargo office and Fire buildings. As per our civil engineering knowledge we detected following damages which are summarized below: International Terminal Building: As per visual survey there were no observed structural issues at the international terminal building. The minor non-structural issues were observed mainly on floors, toilets, and false ceiling and expansion joints. Cracks are observed at some joints. To clarify the damage hereby photographs are attached for detailed description. Crack and spalling of tiles at Toilet of indianstherile hall Crack observed at floor Remedial measures: Repairing works to be carried out as soon as possible. Domestic Terminal Building: In the existing domestic terminal building severe cracks are observed at toilet and some parts of the VIP crossing. At other parts no severe structural damage is observed. 3

4 Crack at wall in toilet Plaster crack Horizontal plaster crack Vertical crack at column Remedial measures: Immediate Repair of the affected areas. 4

5 Cargo building: Crack observed mainly at second floor of cargo building at general administration and financial administration room. Crack on wall Vertical shear crack at wall Shear crack Gap observed between ceiling and wall Remedial measures: Minor Repair needed for wall cracks. epoxy or other joint filling methods required for wider cracks repair. 5

6 New Domestic Terminal Building: The new domestic terminal has non-structural damage that may turn into hazards if an aftershock takes place. These issues include potential for wall collapse or second-story shifting. This is a concern, given passengers must walk through the new domestic terminal (which remains under construction) to access the operable old domestic terminal. The damages are clearly shown on the photograph below: Cracking at second-floor column is present. Column is hollow, and surrounded by bricks that could fall and harm someone. Cracking at second-floor column is present. Column is hallow, and surrounded by bricks that could fall and harm someone. Main entrance to new domestic terminal needs to be shored. Without shoring, an aftershock may cause wall above doors to fall. Visible cracks were seen in concrete base support on second level of new domestic terminal. Load-barriering column cracked Floor has separated from column on second deck 6

7 Remedial Measures Shore the main entrance to avoid door/wall collapse. Create a walking corridor so that passengers accessing the old domestic terminal expedite their movement through the new domestic terminal and do not sit or loiter. Passengers and the general public are currently sitting in the new domestic terminal because it provides shade and shelter. Conduct repairs to earthquake damaged areas that could potentially become more problematic in the future. These repairs should consist of full demolition and rebuild instead of repairing in place. Fire Building Column and wall failure staircase crack Remedial Measures Immediate maintenance by demolishing the affected area. Recommendations 1. The maintenance work should be carried out as soon as possible to give a safe environment for working and also to build confidence of all staff. 2. Detailed inspection and assessment of structural damages and other safety issues is required to be carried out from trained structural/ earthquake engineers/ consultants to ascertain what kind of corrective actions are needed for prolonged use of the building for each types of defects. 7

8 Runway and Taxiway: Parallel Taxiway Transverse Crack at Chainage m. Similar types of cracks are seen at the transverse direction at exit Taxiway "D" and "B". 8

9 Runway Transverse directional crack at Chainage m Runway Transverse Crack at Chainage Recommendations in the initial phase, all the cracks should be properly sealed with bituminous materials to control further water seepage from the surface. immediate permanent sealing is required for cracks upto full depth to prevent the water infiltration into the pavement layers by using appropriate sealing materials. 9

10 Overall Conclusion of rapid observation: There were no observed structural issues at the international terminal and the old domestic terminal. Minor non-structural issues, such as cracked paint, falling of false ceiling, breakage of floor marble and window glasses were observed. Expansion joints at international terminal building and operations/airlines Building needs to be repair and needs more water proofing works in joints and flat/sloped roof of building due to minor cracks developed by shaking. The new domestic terminal has non-structural damage and should be removed some part of partition wall and needs some rectification. similarly the adjoining building near water tank at fire station need immediate repair and retrofitting which is comparatively more damaged building in TIA. VVIP Building observed some minor damages such as breakage of ceiling decoration, falling of wooden craft windows etc. There is not any significant damages in pavement surface of Runway, Taxiway and Apron during visual inspection. To assure the rated strength of pavement, It should require to re-evaluate pavement strength including sub surface condition by using extensive pavement evaluation methods. Inspected By: Er. Hari Adhikari, Chief, Civil Engineering Division Er. Binesh Munakarmi, Senior Officer Er. Shradha Shrestha, Senior Assistant Er. Nirmal Poudel, Senior Assistant 10