Traumatisme

The effects of IZMIT's earthquake in industrial plants

Some data on the earthquake

The earthquake, arisen on August 17, 1999 to Izmit ( Kocaeli), Turkey, of magnitude 7.4, is not exceptional in this region (7 earthquakes of magnitude superior to 7 since 1939); accelerations on the ground, between 0,2 g and 0,4 g in the stricken zones, are rather moderate considering the magnitude.

The affected zone, situated in the southeast of Istanbul, near the Sea of Marmara, extends on 200 kilometres in length and 50 kilometres in width in a region with strong density of populations and industrial plants (13 % of the industrial production of Turkey). The biggest industrial damage concerned an oil refinery, stopped for several months essentially following the fall of a tack on installations and a fire in six floating.

At the request of the Direction of the Prevention of Pollutions and Risks of the Ministry of the Regional development and the Environment (MATE) , the INERIS studied:

- Intervention in urgent situation within the framework of the fire six floating roof tanks of liquid hydrocarbons arisen in Izmit's refinery,
- The effects of the earthquake in industrial installations of Izmit's region.

First phase, realized from 19 till 21 August 1999, in contact with the Direction of the Defence and the Civil Safety of the Home Office, allowed to put in evidence the difficulty of implementation of means of intervention on such a fire of tubs.

Second phase was assured from 2 till 11 September 1999 in contact with the mission, led to the same dates, of the French ( AFPS) Association of Parasismic Engineering. Nine industrial plantss were also visited, for some of them with the assistance of the Chamber of Izmit's industry. Damages on the buildings were also examined.

Visited plants

These plants were quite situated in the neighborhood of the Sea of Marmara, often on alluvial grounds or embankments. The observations which follow were collected during visits, but no document was supplied. Information below about damages is supplied as a rough guide and is not complete.

Visited installations were:

- A cement work; installation suffered only minor damages and was able to quickly restart,
- A refinery where damages concerned different tanks, la jetty, a stack which collapsed, a control room, the buried network for water supply against fire,

- An installation of stocking liquid petroleum gas (LPG), for filling domestic bottles and lorries where damages were very minor and did not prevent a fast restart,

- An installation manufacturer of chlorinated by-products, where the chlorine was made by électrolyse, but was not stored; a lot of electrolytic cells underwent damages, buildings presented minor damages, a jetty collapsed in sea on 125m,

- An installation of stocking of liquid organic products where damages were minor,

- An installation of manufacture of aluminium profiles where certain buildings with concrete frame (concrete beams walled in with bricks and mortar or concrete slabs) " collapsed,

- An installation of manufacture of plastic pipes where buildings with concrete frame (concrete beams walled in with bricks and mortar or concrete slabs) collapsed by killing two workers,

- A motor factory in the course of construction in the neighborhood of the fault where a building underwent minor damages,

- An installation of manufacture of acrylic polymers where three reservoirs let escape their contents in the corresponding concrete retention pools, 250 m of jetty collapsed in sea and where a channeling in concrete conveying some process to bewater broke and has replaced.

Synthesis of observations

The group of observations made on buildings, including industrial, shows that when these were built as concrete frame (concrete beams walled in with bricks and mortar or concrete slabs) , more or less total collapses occurred. Hurt structures, with the exception of a 130 m high stak in a refinery behaved well generally , as well as above ground pipes and their supports. Buried pipes for gas and water sometimes broke. LPG spherical and cylindrical reservoirs under pressure all behaved well. The atmospheric reservoirs were able to lead either to a massive leak of their contents - 6500 tons of toxic product resulted from the break guillotine on three outlet pipes at the bottom of reservoirs, or in the absence of leak in the deformations " in paw of elephant " of their base or in deformations of their roofs.

Globally the process equipments underwent few damages and the energy supplies worked.

Jetties sometimes disappeared on a part of their length in the heart of the sea.

Finally, it was noted the effects of subsidence (but rarely in the zone of visited industrial installations, except for the motor factory in construction), but especially of landslide submarine very important for the neighborhood of the seaside in front of certain visited industrial installations.

Main accidental scenarios

Main accidental scenarios were the following ones:

- The refinery suffered during five days from a fire having concerned on the whole six naphta tanks, sets on fire which did not fortunately propagate in the other reservoirs or installations, considering the fixed and mobile devices operated to cool tsurrounding equipments and the installations surrounding.

- In an installation of manufacture of acrylic polymers, a leak of 6500 tons of acrylonitrile led to the death of the fauna nearby because of the forming of a toxic cloud; this product poured out in corresponding concrete retention pools from three reservoirs following a break guillotine on three outlet pipes at the bottom of these reservoirs; a ground pollutionoccurred also because of cracks appeared in these retention pools during the earthquake.

- A liquid petroleum gas connecting the refinery with spheres of stocking of a nearby installation broke during the earthquake, led to the forming of a cloud which was fired with a lorry crossing the cloud and ledto the fire of a nearby paint storage and to the fire of lorries with two deaths; the lorries drivers.

F. Masson, J. P. Pineau et J. J. Tritsch.

INERIS-Verneuil en Halatte

For addtional information on industrial installations and for other aspects concerning the earthquake, one can address the AFPS (Phone : 33 ( 0 ) 1 44 58 28 40) which eissueda report of its mission organized under the aegis of the MATE.

NDLR : As we are not had to wonder from a point of view cindynique about a possible contradiction enter this vision of industrial damages, as matter of fact moderated, while human losses and property damages seemed very high.

It is the occasion to announce that our colleagues of the Cindynic's Mediterranean Institute will organize in October, 2000 a colloquium on this earthquake and that of Taïwan.