建筑设计毕业论文中英文资料外文翻译文献(编辑修改稿)

建筑设计毕业论文中英文资料外文翻译文献(编辑修改稿)内容摘要：

liable uptodate information on excavators, loaders and transport is obtainable from the makers. Earthworks or earthmoving means cutting into ground where its surface is too high ( cuts ), and dumping the earth in other places where the surface is too low ( fills). Toreduce earthwork costs, the volume of the fills should be equal to the volume of the cuts and wherever possible the cuts should be placednear to fills of equal volume so as to reduce transport and double handlingof the fill. This work of earthwork design falls on the engineer who lays out the road since it is the layout of the earthwork more than anything else which decides its cheapness. From the available maps ahd levels, the engineering must try to reach as many decisions as possible in the drawing office by drawing cross sections of the earthwork. On the site when further information bees available he can make changes in jis sections and layout,but the drawing lffice work will not have been lost. It will have helped him to reach the best solution in the shortest time. The cheapest way of moving earth is to take it directly out of the cut and drop it as fill with the same machine. This is not always possible, but when it canbe done it is ideal, being both quick and cheap. Draglines, bulldozers and face shovels an do this. The largest radius is obtained with the dragline,and the largest tonnage of earth is moved by the bulldozer, though only over short disadvantages of the dragline are that it must dig below itself, it cannot dig with force into pacted material, it cannot dig on steep slopws, and its dumping and digging are not accurate. Face shovels are between bulldozers and draglines, having a larger radius of action than bulldozers but less than draglines. They are anle to dig into a vertical cliff face in a way which would be dangerous tor a bulldozer operator and impossible for a dragline. Each piece of equipment should be level of their tracks and for deep digs in pact material a backacter is most useful, but its dumping radius is considerably less than that of the same escavator fitted with a face shovel. Rubbertyred bowl scrapers are indispensable for fairly level digging where the distance of transport is too much tor a dragline or face shovel. They can dig the material deeply ( but only below themselves ) to a fairly flat surface, carry it hundreds of meters if need be, then drop it and level it roughly during the dumping. For hard digging it is often found economical to keep a pusher tractor ( wheeled or tracked ) on the digging site, to push each scraper as it returns to dig. As soon as the scraper is full,the pusher tractor returns to the beginning of the dig to heop to help the nest scraper. Bowl scrapers are often extremely powerful machines。 many makers build scrapers of 8 cubic meters struck capacity, which carry 10 m 179。 heaped. The largest selfpropelled scrapers are of 19 m 179。 struck capacity ( 25 m 179。 heaped )and they are driven by a tractor engine of 430 horsepowers. Dumpers are probably the monest rubbertyred transport since they can also conveniently be used for carrying concrete or other building materials. Dumpers have the earth container over the front axle on large rubbertyred wheels, and the container tips forwards on most types, though in articulated dumpers the direction of tip can be widely varied. The smallest dumpers have a capacity of about m 179。 , and the largest standard types are of about m 179。 . Special types include the selfloading dumper of up to 4 m 179。 and the articulated type of about m 179。 . The distinction between dumpers and dump trucks must be remembered .dumpers tip forwards and the driver sits behind the load. Dump trucks are heavy, strengthened tipping lorries, the driver travels in front lf the load and the load is dumped behind him, so they are sometimes called reardump trucks. of Structures The principal scope of specifications is to provide general principles and putational methods in order to verify safety of structures. The “ safety factor ”, which according to modern trends is independent of the nature and bination of the materials used, can usually be defined as the ratio between the conditions. This ratio is also proportional to the inverse of the probability ( risk ) of failure of the structure. Failure has to be considered not only as overall collapse of the structure but also as unserviceability or, according to a more precise. Common definition. As the reaching of a “ limit state ” which causes the construction not to acplish the task it was designed for. There are two categories of limit state : (1)Ultimate limit sate, which corresponds to the highest value of the loadbearing capacity. Examples include local buckling or global instability of the structure。 failure of some sections and subsequent transformation of the structure into a mechanism。 failure by fatigue。 elastic or plastic deformation or cr。