Study On Exploitation & Utilization Of The Underground Space Within The City's Central District Of Xi'an City

In the context of the special scientific research named Research on Rational Development of the Underground Space in Xi'an City under the educational department of Shanxi province, this thesis researches and analyses the present utilized situation, applicability and functional demand of underground space within the Ming Dynasty wall located downtown area in Xi'an city proper as well as some major problems of exploiting such underground space.First, based on the history and present situation of underground space exploitation abroad , this thesis systematically discourses on some basic theories of exploiting underground space, and puts forward that importance should be attached to resource properties of underground space, instead of regarding it only as "substitution" of ground space.Then, through investigating and analyzing the present utilized situation of the underground space within Ming Dynasty wall, the author comes to such conclusions as follows: it's a good chance of exploiting and utilizing the underground space of within Ming Dynasty wall; the exploitation and utilization of the underground space of within Ming Dynasty wall is still at preliminary stage; the exploitation and utilization of the underground space in some key regions lacks macroplanning and is sort of short-term action; it's urgent to lay out a feasible construction blueprint in the near future.Also, on the basis of quantitative analysis of the quantum of the ground space and upwards resources and the underground space resources within Ming Dynasty wall, the author points out that the quantum of resources scale of the ground space and upwards resources is relative small, whereas the exploitation and utilization of the underground space can solve the problem; studies the applicability of the underground space within Ming-dynasty wall; analyses and models the priority in the development of fast city communication facilities, business and entertainment facilities, public facilities and static city communication facilities with analytical hierarchy process (AHP) method and the result of the modeling analysis shows that the exploitation and utilization of the underground space within Ming Dynasty wall should follow the following order: underground business and entertainment facilities, fast underground communication, underground public facilities and static communication facilities.Finally, according to the geological environment status and the technological level of underground space exploitation in local area, this thesis analyses some prevalent engineering problems that may appear in the process of actualization of underground project and the impact on the exploitation and utilization of underground space within Ming Dynasty wall. On the whole, the engineering geological condition of exploiting and utilizing the underground space within Ming-dynasty wall is ok, for its structure of earth body and mechanical property are both good for underground construction; it also points out that attention needs to be paid to distinguishing the artificial filling when exploiting the shallow layer of underground space within Ming Dynasty wall, as such filling has an inferior engineering property; and the mass use of anchor rod ＆ brad is not good for the long-term development of underground space; it's necessary to establish a synthetic information bank for city underground engineering to keep the types of underground engineering for various purposes and kinds of design parameters (buried depth, structural dimension and form, supporting course, influential sphere of fundament, etc.) on file so as to promote the sustainable development of the exploitation and utilization of city underground space.