【正文】 nd maispan closures were cast, the travelers had to be removed from locations adjacent to the towers rather than over water so as to avoid any influence on canal traffic. To save time, the towers approach structure, and piers were built approach viaducts were designed and built using the spanbyspan erection method by means of an underslung suupport east viaduct span was built first and the support truss was then removed and transferred to the west side so that it could be used to build the three spans of the west viaduct, one span at a time. The bridge construction was pleteed in Auguse 2020 at a cost of approximately $2,780 per square opening awaits the pletion of the rest of the highway it serves. 跨越世紀(jì)之橋 1962 年，橫跨巴拿馬運(yùn)河的美國(guó)大橋作為僅有的固定連接開(kāi)放交通車(chē)。the probability that it will be exceeded within 50 years is 2 pencent and within 100 years,4 persent. Because of uncertainty about the direction from which the seismic waves would approach the site, a single response spectruma curve showing the mathematically puted maximum response of a set of simple damped harmonic oscillators of different natural frequencies to a particular earthquake ground accelerationwas used to characterize mitions in two mutually orthogonal directions in the horizontal conduct a timehistory analysis of the bridge’s multiple supports,a set of synthetic motions with three ponentslongitudinal,transverse,and verticalwas developd using an iterative ground motions from an earthquake in Chile in 1985 were used as “seed”motions for the sythesis process. A time delay estimatethat is,an estimate of the time it would take for the motions generated by the SEEand FEE earthquakes to travel from one point to the nextwas create using the assumed seismic wave velocity and the distance between the piers of the an assumed was velocity of approximately ,a delay on the order of half a second to a second is appropriate for a bridge 1 to 2km long. Soilfoundation interaction studies were performed to determine the stiffness of the soil and foundation as well as the seismic excitation measurement that would be used in the dynamic studieswere conducted by means of soilpile models using linear and nonlinear soil layera of varying equivalent pile lengths in the studiesthat is, the lengths representing the portions of a given pile that would actually be affected by a given earthquakeinduced ground motionranged such a threedimensional model,there are six ways in which the soil can resist the movement of the lpile because of its stiffness:throngh axial force in the three directions and through bending moments in three the bridge site contains so many layers of varying soil types,each layer had to be represented by a different stiffness matrix and then analyzed. Once the above analyses were pleted,the International engineerstaking into consideration the project requirements developedby the owenerevaluated several different concrete cablestayed number of structural systems were investigated,the main variables,superstructure cross sections,and the varying support conditions described above. The requirement that the evevation of the deck be quite high strongly influenced the tower the proposed deck elevation of more than 80m,the most economical tower shapes included singleand dualmast towers as well as “goal post”towersthat is,a design in which the two masts would be linked to each other by crossbeams. Ultimately the engineers designd the bridge to be wide with a 420mlong cablestayd main span,two 200mlong side spansone on each side of the main spanand approach structures at the ends of the side the east side there is one 46m long concrete approach structure,while on the west side there are three,measuring 60,60,and 66m,for a total bridge length of 1, side spans are supported by four piers,referred to,from west to east,as ,P3,and P4. The bridge deck is a continuous singlecell box girder from abutment to abutment。 A design that would adhere to the American Association of State Highway and Transportation Official standard for a 100year service life and offer HS25 truck loading。中文 4735 字 畢業(yè)設(shè)計(jì) 外文翻譯 題 目 跨 越 世 紀(jì) 之 橋 專(zhuān) 業(yè) 土木工程（橋梁） 2020 年 6 月 A Bridge For All Centuries An extremely longand record settingmain span was designed for the second bridge to across the Panama Canal in order to meet the owner’s requirement that no piers be placed in the no disruption of canal traffic was permitted at any time,the cablestayed bridge of castinplace cancrete was carefully constructed using the balancedcantilever method. In 1962 ,the Bridge of Americas(Puente de las America) opened to traffic,serving as the only fixed link across the Panama Canal .The bridge was designed to carry 60,000 vehicles per day on four lanes, but it has beenoperating above its capacity for many bottlenecks on the route that the bridge carries over the canalthe PanAmerican Highway(InterAmerican Highway)and promotegrowth on the western side of Panama,the country’s Ministry of Public Works(Ministerio de Obras Publicas,or MOP )decided to build a new highway systerm linking the northern part of Panama City,on the eastern side of the canal, to the town of Arra