建筑土木畢業設計中英文翻譯--建筑及高層建筑的組成(編輯修改稿)

　

【文章內容簡介】 fresh air from central fan rooms and air conditioning machinery. The ceiling, which is suspended below the upper floor construction, conceals the ductwork and contains the lighting units. Electrical wiring for power and for telephone munication may also be located in this ceiling space or may be buried in the floor construction in pipes or conduits.There have been attempts to incorporate the mechanical and electrical systems into the architecture of building by frankly expressing them； for example, the American Republic Insurance Company Building(1965) in Des Moines, Iowa, exposes both the ducts and the floor structure in an organized and elegant pattern and dispenses with the suspended ceiling. This type of approach makes it possible to reduce the cost of the building and permits innovations, such as in the span of the structure.6. Soils and FoundationsAll building are supported on the ground, and therefore the nature of the soil bees an extremely important consideration in the design of any building. The design of a foundation dependson many soil factors, such as type of soil, soil stratification, thickness of soil lavers and their paction, and groundwater conditions. Soils rarely have a single position； they generally are mixtures in layers of varying thickness. For evaluation, soils are graded according to particle size, which increases from silt to clay to sand to gravel to rock. In general, the larger particle soils will support heavier loads than the smaller ones. The hardest rock can support loads up to 100 tons per square foot( metric tons/sq meter), but the softest silt can support a load of only ton per square foot( metric tons/sq meter). All soils beneath the surface are in a state of paction； that is, they are under a pressure that is equal to the weight of the soil column above it. Many soils (except for most sands and gavels) exhibit elastic properties—they deform when pressed under load and rebound when the load is removed. The elasticity of soils is often timedependent, that is, deformations of the soil occur over a length of time which may vary from minutes to years after a load is imposed. Over a period of time, a building may settle if it imposes a load on the soil greater than the natural paction weight of the soil. Conversely, a building may heave if it imposes loads on the soil smaller than the natural paction weight. The soil may also flow under the weight of a building； that is, it tends to be squeezed out.Due to both the paction and flow effects, buildings tend settle. Uneven settlements, exemplified by the leaning towers in Pisa and Bologna, can have damaging effects—the building may lean, walls and partitions may crack, windows and doors may bee inoperative, and, in the extreme, a building may collapse. Uniform settlements are not so serious, although extreme conditions, such as those in Mexico City, can have serious co