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1、题目：桥梁工程和桥梁美学 Title:：BRIDGE ENGINEERING AND AESTHETICS专 业： 土木工程 班 级： 土木111班 学 号： 110711132 姓 名： 傅明涛 指导教师： 庞传琴 完成日期：2016年6月11日Evolvement of bridge Engineering,brief reviewAmong the early documented reviews of construction materials and structure types are the books of Marcus Vitruvios Pollio in the fi

2、rst century B.C.The basic principles of statics were developed by the Greeks , and were exemplified in works and applications by Leonardo da Vinci,Cardeno,and Galileo.In the fifteenth and sixteenth century, engineers seemed to be unaware of this record , and relied solely on experience and tradition

3、 for building bridges and aqueducts .The state of the art changed rapidly toward the end of the seventeenth century when Leibnitz, Newton, and Bernoulli introduced mathematical formulations. Published works by Lahire （1695）and Belidor （1792） about the theoretical analysis of structures provided the

4、basis in the field of mechanics of materials .Kuzmanovic（1977） focuses on stone and wood as the first bridge-building materials. Iron was introduced during the transitional period from wood to steel .According to recent records , concrete was used in France as early as 1840 for a bridge 39 feet （12

5、m） long to span the Garoyne Canal at Grisoles, but reinforced concrete was not introduced in bridge construction until the beginning of this century . Prestressed concrete was first used in 1927.Stone bridges of the arch type （integrated superstructure and substructure） were constructed in Rome and

6、other European cities in the middle ages . These arches were half-circular , with flat arches beginning to dominate bridge work during the Renaissance period. This concept was markedly improved at the end of the eighteenth century and found structurally adequate to accommodate future railroad loads

7、. In terms of analysis and use of materials , stone bridges have not changed much ,but the theoretical treatment was improved by introducing the pressure-line concept in the early 1670s（Lahire, 1695） . The arch theory was documented in model tests where typical failure modes were considered （Frezier

8、,1739）.Culmann（1851） introduced the elastic center method for fixed-end arches, and showed that three redundant parameters can be found by the use of three equations of coMPatibility.Wooden trusses were used in bridges during the sixteenth century when Palladio built triangular frames for bridge spa

9、ns 10 feet long . This effort also focused on the three basic principles og bridge design : convenience（serviceability） ,appearance , and endurance（strength） . several timber truss bridges were constructed in western Europe beginning in the 1750s with spans up to 200 feet （61m） supported on stone su

10、bstructures .Significant progress was possible in the United States and Russia during the nineteenth century ,prompted by the need to cross major rivers and by an abundance of suitable timber . Favorable economic considerations included initial low cost and fast construction .The transition from woo

11、den bridges to steel types probably did not begin until about 1840 ,although the first documented use of iron in bridges was the chain bridge built in 1734 across the Oder River in Prussia . The first truss completely made of iron was in 1840 in the United States , followed by England in 1845 , Germ

12、any in 1853 , and Russia in 1857 . In 1840 , the first iron arch truss bridge was built across the Erie Canal at Utica . The Impetus of Analysis The theory of structures ,developed mainly in the ninetheenth century,focused on truss analysis, with the first book on bridges written in 1811. The Warren

13、 triangular truss was introduced in 1846 , supplemented by a method for calculating the correcet forces .I-beams fabricated from plates became popular in England and were used in short-span bridges.In 1866, Culmann explained the principles of cantilever truss bridges, and one year later the first ca

14、ntilever bridge was built across the Main River in Hassfurt, Germany, with a center span of 425 feet （130m） . The first cantilever bridge in the United States was built in 1875 across the Kentucky River.A most impressive railway cantilever bridge in the nineteenth century was the First of Forth brid

15、ge , built between 1883 and 1893 , with span magnitudes of 1711 feet （521.5m）.At about the same time , structural steel was introduced as a prime material in bridge work , although its quality was often poor . Several early examples are the Eads bridge in St.Louis ; the Brooklyn bridge in New York ;

16、 and the Glasgow bridge in Missouri , all completed between 1874 and 1883.Among the analytical and design progress to be mentioned are the contributions of Maxwell , particularly for certain statically indeterminate trusses ; the books by Cremona （1872） on graphical statics; the force method redefin

17、ed by Mohr; and the works by Clapeyron who introduced the three-moment equations.The Impetus of New MaterialsSince the beginning of the twentieth century , concrete has taken its place as one of the most useful and important structural materials . Because of the coMParative ease with which it can be

18、 molded into any desired shape , its structural uses are almost unlimited . Wherever Portland cement and suitable aggregates are available , it can replace other materials for certain types of structures, such as bridge substructure and foundation elements .In addition , the introduction of reinforc

19、ed concrete in multispan frames at the beginning of this century imposed new analytical requirements . Structures of a high order of redundancy could not be analyzed with the classical methods of the nineteenth century .The importance of joint rotation was already demonstrated by Manderla （1880） and

20、 Bendixen （1914） , who developed relationships between joint moments and angular rotations from which the unknown moments can be obtained ,the so called slope-deflection method .More simplifications in frame analysis were made possible by the work of Calisev （1923） , who used successive approximatio

21、ns to reduce the system of equations to one simple expression for each iteration step . This approach was further refined and integrated by Cross （1930） in what is known as the method of moment distribution .One of the most import important recent developments in the area of analytical procedures is

22、 the extension of design to cover the elastic-plastic range , also known as load factor or ultimate design. Plastic analysis was introduced with some practical observations by Tresca （1846） ; and was formulated by Saint-Venant （1870） , The concept of plasticity attracted researchers and engineers af

23、ter World War , mainly in Germany , with the center of activity shifting to England and the United States after World War .The probabilistic approach is a new design concept that is expected to replace the classical deterministic methodology.A main step forward was the 1969 addition of the Federal H

24、ighway Adiministration （FHWA）”Criteria for Reinforced Concrete Bridge Members “ that covers strength and serviceability at ultimate design . This was prepared for use in conjunction with the 1969 American Association of State Highway Offficials （AASHO） Standard Specification, and was presented in a

25、format that is readily adaptable to the development of ultimate design specifications .According to this document , the proportioning of reinforced concrete members （ including columns ） may be limited by various stages of behavior : elastic , cracked , and ultimate . Design axial loads , or design

26、shears . Structural capacity is the reaction phase , and all calculated modified strength values derived from theoretical strengths are the capacity values , such as moment capacity ,axial load capacity ,or shear capacity .At serviceability states , investigations may also be necessary for deflectio

27、ns , maximum crack width , and fatigue .Bridge Types A notable bridge type is the suspension bridge , with the first example built in the United States in 1796. Problems of dynamic stability were investigated after the Tacoma bridge collapse , and this work led to significant theoretical contributio

28、ns Steinman （ 1929 ） summarizes about 250 suspension bridges built throughout the world between 1741 and 1928 .With the introduction of the interstate system and the need to provide structures at grade separations , certain bridge types have taken a strong place in bridge practice. These include con

29、crete superstructures （slab ,T-beams,concrete box girders ）, steel beam and plate girders , steel box girders , composite construction , orthotropic plates , segmental construction , curved girders ,and cable-stayed bridges . Prefabricated members are given serious consideration , while interest in

30、box sections remains strong .Bridge Appearance and Aesthetics Grimm （ 1975 ） documents the first recorded legislative effort to control the appearance of the built environment . This occurred in 1647 when the Council of New Amsterdam appointed three officials . In 1954 , the Supreme Court of the Uni

31、ted States held that it is within the power of the legislature to determine that communities should be attractive as well as healthy , spacious as well as clean , and balanced as well as patrolled . The Environmental Policy Act of 1969 directs all agencies of the federal government to identify and d

32、evelop methods and procedures to ensure that presently unquantified environmental amentities and values are given appropriate consideration in decision making along with economic and technical aspects . Although in many civil engineering works aesthetics has been practiced almost intuitively , particularly in the past , bridge engineers have not ignored or neglected the aesthetic disciplines .Recent research on the subject appears to lead to a rationalized aesthetic design methodology （Grimm and Preiser , 1976 ） .Work has been done on the aest