DAMAGE FOR BUILDINGS OF DIFFERENT TYPE.

During the earthquake of 4.02.1868 in Tashkent some buildings of local materials were turned over.

During the earthquake of 4.04.1868 in Tashkent there were damages of buildings (corners fell down) and collapse of walls of loam-houses. There were killed and wounded peoples.

During the earthquake of 29.11.1886 in Tashkent there were collapsed 7 buildings. The Russian part of the city was more destroyed than Asian. Buildings in the Russian part of the city were mostly from adobe bricks with the height, bays and steps of walls exceeding the mentioned sizes of Asian part of the city. Asian buildings were loam-houses (gpakhsaf type) with wooden frames and adobe filler (esynchf type).

During the earthquake of 1966 adobe buildings got much more damages in both quantity and in intensity. Before the earthquake the residential fund of Tashkent enumerated 7.2 mln m2. As a result of the earthquake more than 35,000 of local construction were collapsed and it was 2.8 mln m2. There were no cases of destruction of buildings of modern construction.

During Nazarbek earthquake of 11.12.1980 in Tashkent fully collapsed buildings both of local and modem construction were not found.

BRIEF DESCRIPTION OF DAMAGES ON EACH TYPE OF BUILDINGS.

Typical damages of the buildings of local construction were: separation of longitudinal walls from the cross ones, full collapse of the walls not loaded with ceilings, collapse of corners of the buildings, lamination of brick walls, collapse of pins, collapse of brick setting in the places of joining buildings of different height, diagonal and horizontal cracks of walls. Multistorey buildings in Tashkent were presented by 10-12 4-storey buildings, built in 40-50-th with wooden ceilings without aseismic measures. Those buildings were within 8-ball zone of Tashkent. Typical damages of those buildings were:  diagonal and horizontal cracks in single piered elements. X-type cracks in brick setting between apertures, diagonal and horizontal cracks in staircases. Actually all the buildings were restored. Residential inultistorey buildings were presented by brick buildings of series 1-310 and 1-310 I. In the project the buildings have simple rectangular plan scheme with uniform and symmetrical placing of capital walls and consist of settle butt ordinary sections. The height -4-5 floors. Cross walls are bearing with step 6.0 and 2.8 m. Strip foundations under the walls are of two versions. Monolith of rubble-concrete and prefabricated pillow block. The foundations of terraces - monolith concrete, column (concrete M-100). For pinth and walls according to the project brick setting of I category. Join of outward and inner walls and also parts of walls, weakened by canals, are reinforced by horizontal net reinforcing. Separating diaphragm - prefabricated reinforced concrete. Diaphragm floor are from round-hollow panels and reinforced concrete belts.

To the most frequent serious damages found on buildings situated in the epicentral zone, may be referred diagonal and cross cracks in single piered elements and walls; cracks in junctions of ceilings with walls and between walls, cracks in the places of reinforced concrete ceilings resting, opening junctions between slabs of ceilings.

Thus, during Tashkent earthquake major damaged were only those 8 - ball designed buildings of 1-310 I, which were situated in epicentral zone, that is subjected to seismic loads close to designed.

Frame residential buildings in Tashkent for the moment of the earthquake have not been built yet. Though it is necessary to point out that frame public buildings situated in the epicenter zone had minor damages. The damages were found only in bearing structures and separation walls. There were diagonal cracks in brick surrounding structures and separation walls, crack along the contour of filling, tearing walls away from frames. There were more damages in upper storeys.

Large panel buildings of TDSK and 1 Uz-500 series in the result of Tashkent earthquake were not tested on seismic load because the earthquake intensity in the region of their dislocation did not exceed 6 balls while designed basic earthquake was 6 balls. Observed hair cracks in panels and junctions are similar to contraction or temperature-exploitation ones. That is why behaviour of large panel buildings is not described here.

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Data source (Country report)

1.      Name: NURTAEV Bakhtiar

2.      Organization: Institute of Geology and Geophysics, Academy of Sciences of Uzbekistan

3.      Course: 1998 Sm 

4.      Title:

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