Documentof The World Bank Public Disclosure Authorized Report No. T-7233-CHA TECHNICAL ANNEX Public Disclosure Authorized THE PEOPLE'S REPUBLIC OF CHINA HEBEI EARTHQUAKE REHABILITATION PROJECT Public Disclosure Authorized May 4, 1998 Public Disclosure Authorized Urban Development Sector Unit East Asia and Pacific Regional Office CURRENCY EQUIVALENTS (As of March 1, 1998) Currency = Renminbi Currency Unit = Yuan (Y) Y 1.00 = $0.12 $1.00 Y 8.3 FISCAL YEAR January 1 - December 31 UNITS OF MEASURES 1 meter (m) = 39.37 inches 1 kilometer (km) = 0.62 miles 1 hectare (ha) = 2.47 acres ACRONYMS AND ABBREVIATIONS HP Hebei Province HPG Hebei Provincial Government MOF Ministry of Finance PMO Project Management Office ZM Zhangjiakou Municipality ZMG Zhangjiakou Municipal Government Vice President: jean-Michel Severino,EAP CountryDirector: Yukon Huang, EACCF Sector Manager: Keshav Varma, EASUR | Aask Manager: Wiebe Moes, MunicipalEngineer, EASUR CHINA HEBEI EARTHQUAKE REHABILITATION PROJECT TECHNICAL ANNEX Annex 1: Background and Damage Assessment.................................................. 1 Annex 2: Project Description and Organization .................................................. 6 Annex 3: Housing and Public Building Practices, Model Designs and Construction Aspects .................................................. 11 Annex 4: Water C'onservancy Facilities ................................................. 25 Annex 5: Regeneration of Agricultural Productivity................................................. 35 - 1 - ANNEX 1 ANNEX 1: BACKGROUND AND DAMAGE ASSESSMENT Introduction 1. At 11.50 am on January 10, 1998 an earthquake of magnitude 6.2 on the Richter scale occurred on impoverished rural areas on Bashang plateau in Zhangjiakou Municipality. The epicenter was at the border of Zhangbei and Shangyi counties at latitude 41.100 andLlongitude 114.300. The earthquake was followed by a large number of aftershocks, with a total of 481 being recorded in the week following the earthquake. Fifteen of these measured over 4.0 on the Richter scale. 2. Zhangjiakou Municipality consists of the Bashang plateau in the north, bordering on Inner Mongolia, and the Baxia plain to the south. The total area of the municipality is 36,873 square kilometers (km2), containing a total population of 4.4 million. There are four counties located on the Bashang plateau-Zhangbei, Guyuan, Kangbao and Shangyi, with a total area of 12,480 km2. The altitude of the plateau varies from 1,300 to 1,600 meters (m) above sea level. The average annual temperature on the plateau is 2.6°C, and the lowest recorded temperature is -34.8°C. The average length of the frost-free period is 110 days, with a minimum of 70 days. Water resources are scarce, with most of the supply coming from wells. The area supports dryland agriculture, with limited areas of irrigation using groundwater. Soil conditions are poor and the economic base is weak, with per capita incomes of the order of Y 1,000 per year. Damage Assessment 3. There were 49 recorded deaths and 11,439 injuries. The earthquake caused extensive damage over an area of some 2,600 km2 covering Zhangbei, Shangyi and Kangbao counties on the plateau, and Wanquan county adjacent to the plateau. The affected area includes 37 townships, 585 administrative villages and 1,824 other villages with a population of 471,000. Of the above, 15 townships, 281 administrative villages and 696 other villages, containing a total population of 241,000, were seriously affected. Within these areas, the intensity of the earthquake was VIII measured on the modified New China Intensity Scale (NCIS). A total of 136,000 rooms collapsed and a further 264,000 rooms were damaged, leaving a total population of 44,000 homeless. 4. As was the case in the North China earthquake of October 1989 (North China Earthquake Project-Credit 2091-CHA), which struck parts of Shaanxi and Hebei Provinces, village housing suffered the most damage in the earthquake. Housing and other village infrastructure in the affected areas are mainly local timber post and mud- brick and stone construction that is vulnerable to earthquake shocks. Basic building construction techniques have not always been incorporated into traditional building practices. Bonding of corners, securing of gable walls, provision of lintels over openings, -2- ANNEX 1 securing of roof structures, and the construction of the roof itself all too frequently have structural weaknesses built into them. 5. The earthquake has damaged the water supply to some 60,000 villagers in the Zhangbei, Shangyi and Kangbao counties. Some 130 wells need rehabilitation (20 percent repair, 80 percent replacement), and pipelines will be extended to some 90 percent of the households with the remaining villagers relying on standpost supply. The damage to water conservancy works in Zhangbei and Wanquan counties include irrigation canals, office buildings and dormitories. Also, some 730 motor wells for irrigation need repair/ reconstruction, mainly in Zhangbei and Shangyi counties. The Friendship Reservoir, constructed in 1958, is the largest water storage facility in northern Hebei Province. The dam, an earthfill structure of 40 m high and 290 m long, shows a total of 27 cracks on the dam crest and slope failures occurred on both the upstream and downstream dam faces. Additionally, the outlet tunnel and water intake tower were damaged as well as part of the spillway channel and office buildings/dormitories. 6. The total direct economic loss is estimated at Y 2.4 billion, of which rural housing losses are estimated at Y 1.7 billion. The loss of economic and social facilities in the severely affected townships and villages has wrecked the fragile local economy. Although there is some local industry and mining, the local economy is primarily agriculture-dependent. The villagers' barns, stables and grain storage facilities were destroyed or damaged, resulting in stored winter food and animal feed being lost or exposed to the elements. Schools, health centers, wells, irrigation channels, power lines, and other infrastructure were also destroyed or damaged. 7. China has recorded some of the most severe recorded earthquakes in the world. Since 1900, there have been 664 earthquakes with magnitude over 6 on the Richter Scale (RS), of which 107 registered over magnitude 7, or around 30 percent of world earthquakes of that size. The most severe recent earthquake occurred in 1976, registering 7.8 on the Richter Scale, killing over 400,000 people, and substantially destroying the city of Tangshan in Hebei Province, about five hours' journey by rail east of Beijing. The death toll from earthquakes in China in the twentieth century exceeds 600,000, accounting for over 50 percent of the world total. Chinese earthquake specialists have predicted that, after a decade of relative calm, China is entering a period of high seismic activity that is likely to last for 12 to 15 years. Relief Operations 8. Given that it was mid-winter and extremely cold in the earthquake area, the central and local governments' immediate concerns were to provide adequate temporary shelter, fuel, warm clothing and food supplies to the affected people. Governments, supported by the People's Liberation Army (PLA), responded immediately by putting up thermal tents, constructing temporary shelter, and treating, and evacuating where necessary, the injured. Emergency relief supplies and donations were also received from elsewhere in China and abroad. The relief effort was coordinated by a Leading Group -3 - ANNEX 1 established at the level of Zhangjiakou Municipality (ZM), supported by the affected counties' administration. Within one week of the earthquake a preliminary assessment of the damage was made-a feat, given the widespread area that was affected and the bitter cold of the plateau. The technical resources of the local governments were supplemented by a provincial task force drawn from the architectural, engineering and town planning institutes, and supported by experts from the Ministry of Communications (MOC) and State Seismological Bureau (SSB). Damage Mitigation 9. The Tangshan earthquake resulted in a sweeping review of earthquake design codes in China and in 1978 a revised antiseismic Building Design Code for Industrial and Public Buildings was adopted. This code was followed by similar codes for water supply and drainage works, gas and power/heating plants, hydraulic structures, railways, highways and bridges. The effect of the new codes was evident in Zhangjiakou and in the recent Inner Mongolia and Yunnan earthquakes as most of the recently constructed buildings suffered only light damage or none at all. The Hebei Provincial Government (HPG) confirmed that (a) all project-financed reconstructed works (except housing) would be carried out to the latest antiseismic design codes; (b) designs would be to level VIII on the modified New China Intensity Scale; and (c) in line with current practice, the implementing agencies would be required to comply with the earthquake-expert team's recommendations on whether buildings, or parts of buildings, would be demolished for reconstruction or repaired. 10. The Zhangjiakou Municipal and county governments will require the adoption and use of cost-effective earthquake-resistant design and construction methods for housing and other village infrastructure. Planning and design work will take place through March, alfter which the ground conditions would be suitable for starting reconstruction during the six months' construction