A Study Of The Protection And Reinforcement About The Ruins Of Jiaohe, Turpan, China

The Ruins of Jiaohe is announced the first group national major preservation unit of cultural relics by China Government in 1961, Jiaohe Ruins is located near Yarnaiz Groove village, 10 km west of Turpan City, Xinjiang Uygur Autonomous Region, China. It is a well-known ancient city with a history more than 2,000 years along the Silk Road, playing important role in politics, economics, military and cultural exchange between East and West from 2 century B.C to 14 century A.D. with high value in history, art and science. Its architectural technique basically cover whole architectural ones of the different ancient earthen architectures, it is typical representative of ancient earthen architectures in china even in the world. Because the conservation studies of the earthen sites is still not very mature, the conservation practice of the Ruins of Jiaohe will apply good reference for the conservation of other earthen sites.From the viewpoint of rescue protection according to the law of the People's Republic of China on the protection of cultural Relics(2002) and Principles for the Conservation of Heritage Sites in China (2004), field investigation and geotechnical tests are conducted for the present conservation condition, architectural techniques, the lodging environment, soil type and characteristics, the distribute and characteristic of issues. The engineering characteristic of the soil of sites had been studied with advanced scientific instrument; and the cause and mechanism of issues had been analyzed based on the theories and method of the related course, such as Geology, Geotechnical Engineering, Environmental Science, Material Science, Architecture and History. Based these result and the guidance of the new principle of protection culture, the laboratory and field test of protection technologies were carried. Finally the method and means of protection for Jiaohe Acient City were confirmed. The main conclusions are as followings:1. The concept of conservation science of the earthen sites is put forward, the theories system of conservation science of the earthen sites is primarily illustrated, which is generalized, the research of the lodging environment of the earthen sites is base, the analysis of the issues of the earthen sites is core, the condition survey of the earthen sites is means, the conservation practice of the earthen sites is purpose.2. The lodging environment of the Ruins of Jiaohe is systematically studied. The major characteristics of environment of the Ruins of Jiaohe is: A. the strong wind, 17.2～28.4 s/m wind are average for 36.2 days every year. B. the differential temperature is very strong, e.g. the difference of ground temperature as high as 44.5°C between day and night. C. Heavy rains, more than 40mm can accidentally occur, characterized by short time, high intensity within small area. D. The site locates at the new active texture belt. After analyzed the reaction mechanism between the environment and the earthen sites, the results indicate that the main environment factors threatening the sites are the wind and rain in the Northwest arid area of China.3. The architectural configuration and the assessment of values are most important parts of conservation of the earthen sites. This paper illustrates in detail the architectural configuration of the Ruins of Jiaohe. It is found out that the primary construction technique is excavating earth method structure, the stacking mud structure, tamper soil structure, adobe structure and clod one. Excavating earth method and the stacking mud structure are the main ones. This paper also systematically analyzed the historical, artistic, and scientific values of the Ruins of Jiaohe. It has important historical value helping for studying the history of politics, economy, military, culture, religion, transportation, architecture of ancient Western Regions, its artistic value including impressive-looking building, typical wind erosion geography, and daintiness of natural and humanities environment etc. need be integrally and truly protected. Its scientific values including architectural layout and techniques ,and digging well technique etc. need be deeply researched, its values should be fully considered in design of conservation practices.4. The analysis of issues is core in conservation of the earthen sites science, Firstly the three grade classification system about the issues of earthen sites is established , according to the difference of the cause of issues, the manifestation modality of issues, and engendered mechanism of issues divided into section, it benefits to set up the criterion on research about the protection of the earthen sites. Based on the complete condition surveying, this paper analyzed the type and cause of issues of the Ruins of Jiaohe. The results indicate that the main issues of noumenon are slice-peeling, recess and cranny, that the main issue of precipice is collapse.5. Through the lab experiment and the field test, possibility of use of potassium silicate (PS) material and applying techniques in the conservation practices of the Ruins of Jiaohe have been studied. The results indicated that the PS material can improve the capacities of anti-wind erosion and anti-rain erosion abilities of the Ruins of Jiaohe. after reinforcing, the anti-wind erosion capacities of undisturbed samples increases 7-16 times and after reinforcing the remolded samples anti-wind erosion abilities increases 9 times than before treatment under the combinative function of rain and wind erosion. For the field applying of the PS, the paper puts forward to viewpoints that the different techniques should be adopted according to the earthen sites and its type of issues.6 The field tests indicated that the anchoring unit power of bamboo can be adopted 5 kN/m , the anchoring bolting of the single anchor is above 4 kN/ m, its length should not be too long. The bamboo composite anchor is suitable for the reinforcement of the earthen sites. If adopting the cement mortar to be grout material, the anchoring unit power can be adopted 30 kN/m, if adopting the PS-(F+C) to be grout material, its anchoring unit power can be adopted 20 kN/m.7 Based on the study result, conservation practice plan of the Ruins of Jiaohe is designed.