【正文】 的結(jié)構(gòu)布置和特殊的材料，以抵抗相當高的側(cè)向荷載以及變形。同時，這些構(gòu)件還要將風荷載及地震荷載等側(cè)向荷載傳給基礎(chǔ)。這些概念都是針對城市建筑的升級，將 最終導致地表形成更開闊的空間以及更高效更吸引人的全局環(huán)境。更重要的是，通過地下空間的利用，城市人口密度會提高但對環(huán)境的影響會減少。一條從 Marunouchi 到Shinjuku 的高速干線已被設計到 50m 深。 ，形式以及開銷。 地下空間規(guī)劃 對地下空間利用的有效規(guī)劃是發(fā)展地下設施的前奏。普通公司雇員無法承擔住在他們工作的市中心附近而不得不搭乘公汽單程花 個小時從他們負擔的起的住處到公司。隨著人口和經(jīng)濟的增長，農(nóng)業(yè)用地減少，向城市人口運送食物和原材料的問題日益增長。所有這些發(fā)展均涉及地下工程。 通過將特殊器材設備置于地下，城市地表可被更有效地利用，這樣就可釋放出空間供農(nóng)業(yè)和娛樂使用 。地下空間的利用，作為本章要描述的內(nèi)容，將提供針對這些趨勢的解決辦法。這些趨勢同樣導致針對能源繁衍存貯系統(tǒng)以及用于處理危險廢料（包括化學，生物以及放射性廢料）的國家設施設計的改善和提高，同樣也改善了國家高速運輸體系。然而，由于人口增長和城市化，這些土地同樣要被用于創(chuàng)建更廣闊的運輸系統(tǒng)，被用于工商業(yè)的發(fā)展，以及日益增長的住房需求。結(jié)果是市中心土地價格驚人昂貴（高達 50 萬美圓 /平米）并且很難為人們提供住房，交通，設施服務。因為地下設施不具有經(jīng)濟競爭力，因此在考慮建造前必須在美學，環(huán)境或者是社會效應方面給予綜合評估，除非是一些有特殊標志性意義的設施否則將 會造成現(xiàn)階段國家無法承擔或是很勉強承擔的奢侈浪費。 。在東京，新的 KeiyoJR 線深達 40m。地下設施以其自身特點成為一種典型的儲能設施。這一點不僅緩解了堵塞而且提供了更加有效的能源衍生和廢物循環(huán)。 高層建筑的豎向構(gòu)件從上到下逐層對累積的重力和荷載進行傳遞，這就要有較大尺寸的墻體或者柱體來進行承載。 不幸的是，對于高層建筑首先要解決的不僅僅是抗剪問題，還有抵抗力矩和抵抗變形問題。在地震荷載作用下，頂部質(zhì)量的增加將會使側(cè)向荷載劇增。例如，增加較低層柱以及連接大梁的翼緣截面，將可直接減少側(cè)向位移和增加抗彎能力，而不會加大上層樓面的質(zhì)量，否則，地震問題將更加嚴重。 應當注意的是，所有高層建筑的本質(zhì)都是地面支撐的懸臂結(jié)構(gòu)。因此有必要經(jīng)常在兩個相互垂直的方向設置剪力墻，或者在盡可能多的方向布置，以用來抵抗各個方向的側(cè)向荷載。從強度和變形控制角度來說，桁架有著很好的功效，并且管道可以在構(gòu)件之間穿過。還要求由這些結(jié)構(gòu)分體系提供的剛度在各個方向上應大體對稱。因此，框架結(jié)構(gòu)常被視為最好的高層抗震結(jié)構(gòu)。然而，這些規(guī)范往往要求在框架的某 處增設過多的鋼筋，這就增加了施工的難度。 and growing concern for the maintenance and improvement of the environment, especially regarding global warming and the impact of population growth. Underground space utilization, as this chapter describes, offers opportunities for helping address these trends. By moving certain facilities and function underground, surface land in urban areas can be used more effectively , thus freeing space for agricultural and recreational purpose. Similarly, the use of terraced earth sheltered housing. Using underground space also enables humans to live more fortably in densely populated areas while improving the quality of live. On an urban or local level, the use of underground facilities is rising to acmodate the plex demands of today`s society while improving the environment . For example, both urban and rural areas are requiring improved transportation, utility, and recreational services. The state of traffic congestion in many urban areas of the world is at a critical level for the support of basic human living, and it is difficult if not impossible to add new infrastructure at ground level without causing an unacceptable deterioration of the surface environment or an unacceptable relocation of existing land uses and neighborhoods. On a national level in countries around the world, global trends are causing the creation and extension of mining developments and oil or gas recovery at greater depths and in more inaccessible or sensitive locations. Three trends have also led to the developments of improved designs for energy generation and storage systems as well as national facilities for dealing with hazardous waste (including chemical, biological, and radioactive waste ), and improved highspeed national transportation systems .All these developments involve use of the underground . Land Use Pressures Placing facilities underground is a promising method for helping ease land use pressures caused by the growth and urbanization of the world`s population. Although the average population density in the world is not large, the distribution of population is very uneven. A map of population density in the world is not large ,areas of the world are essentially uninhabited . These areas are for the most part deserts ,mountainous regions, or regions of severe cold that do not easily support human habitation. If one examines China ,for example ,the average population density is approximately 100 persons per square kilometer, but the vat majority of the one billionplus population lives on less than 20 percent of the land area. this is the fertile land that can support food production. However, due to population growth, urbanization, and economic growth, this same land must now support extensive transportation systems, industrial and mercial development, and increasing demands for housing, As the population and economy grow, the land available for agriculture shrinks, and the problems of transporting food and raw materials to an urban population increase. By the year 2020 it is estimated that 70 percent of the world`s population will inhabit urban areas. The same trend are evident in Japan, where approximately 80 percent of the land area is mountainous,90 percent of the population lives on the coastal plains, and economic development is concentrated in relatively few economic development is concentrated in relatively few economic centers .The flatlying land is generally the most fertile and is historically the region of settlement . Other factors adding to population density include the traditional building style , which is lowrise , and Japanese law that contain strong provisions for maintenance of access to sunlight .Also ,to retain domestic food production capability , the Japanese government has protected agricultural land from development. The bination of these historical and political factors together with a strong migration of businesses and individuals to the economic centers has created enormous land use pressure. The result is an astronomically high cost of land in city centers (as high as US $500,00 per square meter) and difficulty in an providing housing, transportation, and utility services for the population. Typical business employees cannot afford to live near the city center where they work and may have to mute one to two hours each way from an affordable area. To service the expanding metropolitan area, public agencies must upgrade roads and build new transit lines and utilizes. Land costs for such work are so high that in central Tokyo, the cost of land may represent over 95 percent of the total cost of a project. The problem of land use pressures and related economi