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1.
Clarke was one of the leading engineers in Canada and the United States in 1848 to 1901, working on railroads, waterways, buildings, and primarily bridges. He was a prolific writer with articles not only in ASCE publications but in British technical journals. He also published many articles in Scribners’ and other popular magazines. He was a leader in the formation and running of several major bridge design and construction companies and worked with many leading bridge engineers of the period. He served ASCE for many years starting as a director in 1870 and was elected President of the Society for 1896–1897. Despite his noteworthy career, he is one of the unknown giants of 19th century civil engineering.  相似文献   

2.
O. Chanute, C.E.     
Octave Chanute was one of the leading civil engineers in the United States in the period between 1850 and 1890. His work on eastern and western railroads was unsurpassed. He began his bridge building career in 1856 and designed his last major bridge in 1888. Starting in 1890, he began his study in the work that others conducted in the area of manned flight and designed and tested many of his own gliders. He later assisted the Wright Brothers in their experiments in Dayton and at Kitty Hawk.  相似文献   

3.
George Shattuck Morison (1842–1903) was one of the major contributors to the development of modern bridge engineering practice. His career spanned the era from design by empirical “rules of thumb” to the use of mathematical analysis techniques. Morison pioneered innovations in bridge engineering practice, including the introduction of materials testing and inspection, the development of design and construction specifications, and production of project reports. His major bridges included many crossings of the Missouri River, the great cantilever railroad bridge at Memphis, Tenn., and the Boone, Iowa viaduct. Morison served as President of the American Society of Civil Engineers and was an influential member of the Isthmian Canal Commission, which selected the location of the Panama Canal.  相似文献   

4.
The 19th century saw the United States rise from an agricultural country with settlements primarily along the ocean or navigable rivers to a major industrial power with the country explored and settled. This rapid development was made possible in part by engineers who designed and built our canals and railroads. One such man was Squire Whipple. This paper describes the impact he made on the use of cast and wrought iron in bridge building. In addition he is known worldwide as the man who developed the technique of analyzing a truss and put those ideas into print in his remarkable book of 1847 on bridge building.  相似文献   

5.
The Cabin John Bridge (CJB), located just outside Washington, D.C., is a masonry arch with a central angle of 110°, an intrados radius of 40.9 m (134 ft), and a span of 67 m (220 ft). Construction of the bridge began in 1857 but was not completed until late in 1863 because of suspensions due to lack of appropriations and the Civil War. The CJB is part of the Washington Aqueduct (WA) and is still the longest single-span masonry arch in the United States. The bridge was designated a National Historic Civil Engineering Landmark by the ASCE in 1972. The paper provides context for the bridge design and explains the construction technologies that were used. In the process, French and British influences on American masonry arch design practices at mid-19th century are revealed. The respective roles of Captain Montgomery C. Meigs, the chief engineer of the WA, and Alfred Landon Rives, his assistant engineer, are critically assessed. The paper provides, for the first time, relevant facts on Rives’ education and engineering career. The performance of the bridge over 145 years is reviewed and discussed.  相似文献   

6.
Lenticular-shaped iron truss bridges, built exclusively by the Berlin Bridge Company of East Berlin, Conn., dominated the New England and adjacent area’s modest span bridge market for over a decade at the end of the nineteenth century. This paper examines this phenomenon in the larger context of earlier European development of the lenticular form and, with the assistance of numerous patent drawings and photographs of American lenticular bridges that were either proposed or built prior to the 1883 formation of the Berlin Bridge Company.  相似文献   

7.
The Golden Gate Bridge is one of the best-known engineering structures in the world and was the longest suspension bridge in the world for many years. Its design has generally been attributed to Joseph Strauss, but recent evidence proves that Charles Ellis was the prime designer of the bridge between 1929 and 1931. Strauss fired Ellis in late 1931 and systematically removed any mention of Ellis’ name in his final report on the bridge issued in 1938. It remained for John van der Zee in his book The Gate to set the record straight. This paper makes the case that Strauss violated one of the fundamental ethical canons—that of giving credit where credit is due.  相似文献   

8.
Evaluation and rating of steel truss bridge connections has become imperative for many transportation agencies after the recent collapse of the I-35W Bridge in Minneapolis. Detailed engineering capacity calculations of gusset plate connections are time consuming and thus expensive. Large numbers of connections are in the national inventory and must be evaluated. A screening process and a simplified rapid screening process are proposed for ranking gusset plate connections in steel truss bridges to help bridge engineers identify possible vulnerable connections and aid field inspections. The procedures consider member demands relative to the connection geometric proportions for four different parameters: fasteners, plate tension, plate compression, and overall horizontal shear. The methods are demonstrated for two bridges, including the collapsed I35W Bridge, and clearly identify connections U10 and L11 as vulnerable for three of the four parameter types (fasteners were not identified as vulnerable for these connections). The ranking approach is not proposed as a substitute for thorough, detailed, and expert assessment of the connections, but rather allows rating engineers to more quickly prioritize detailed evaluations in an ordered systematic way from the most likely vulnerable connections to the least likely vulnerable connections. This technique may be considered analogous to performing screening tests on a new patient to indicate the likely medical condition prior to conducting more sophisticated and costly investigations.  相似文献   

9.
Macdonald was one of the leading bridge engineers from 1867 to 1912. His bridges crossed major rivers of the United States and Australia. He was Chief Engineer for several major bridge companies and finished his career as a member of the Board appointed to select the replacement design for the Quebec Bridge that collapsed under construction in 1907.  相似文献   

10.
Cantilever bridge construction can be said to have started with the work of Heinrich Gerber in Germany in 1867. While the principle had been used in many ancient bridges, it was not until Gerber’s work that metal bridges were built using the cantilever principle. The Kentucky High Bridge over the Kentucky River was the first modern cantilever bridge built in the United States. While James Eads had used the cantilever construction method at St. Louis, his bridge acted in service as a series of three arches. The High Bridge, designed by C. Shaler Smith, was one of the most daring and innovative bridges built in the country and carried its load between 1876 and 1912, when it was replaced by Gustave Lindenthal’s three span truss.  相似文献   

11.
The first modern metal cantilever bridge in the United States, using erection methods that were to be utilized in most future cantilever bridges, was by C. C. Schneider across the Niagara Gorge in 1883. The Niagara, saw in order, John Roebling’s Railroad Suspension Bridge, Samuel Keefer’s Honeymoon Suspension Bridge, Edward Serrell’s Lewiston-Queenston Suspension Bridge, Schneider’s cantilever, Leffert Buck’s arch bridge at the falls as well as Buck’s arch built under Roebling’s suspension bridge. Schneider’s bridge had a useful life of over 40 years during a period when rolling stock on the railroads was increasing rapidly. The speed of erection of a new style bridge coupled with its performance makes it one of the most innovative and significant bridges built in the world at the time.  相似文献   

12.
13.
Research has been carried out to evaluate the structural behavior and influence of aging on a century-old steel railroad truss bridge. The structure is located in Connecticut and services a large number of trains traveling into and out of New York City. The trusses are made of built-up members, with either multiple eyebars or laced channel sections. All panel point connections are joined with true pins and the interior panels are indeterminate. The bridge had experienced problems relating to the lateral shifting of some of the middepth pins. This study was carried out to evaluate the structural behavior and live load distribution throughout the bridge. A major component of the research involved extensive field monitoring. The results show that the actual live load distribution is significantly different than expected from conventional analytical approaches that were most likely used in the original design. The load distribution in multiple eyebar elements is far from uniform, and the distribution of shear through indeterminate panels is significantly different than expected from a normal truss analysis. Significant out-of-plane bending was found in the truss due to floorbeam end rotations, which is thought to be the major factor that is causing the pins to move. The study shows the necessity of using field monitoring to better understand the behavior of older bridges prior to the design of renovation approaches.  相似文献   

14.
The first prestressed segmental concrete bridge in the United States opened to traffic was a small bridge in Madison County, Tennessee. The bridge was constructed using prestressed concrete segments and was opened to traffic in October 1950. Prestressed concrete beams were placed side by side to form the superstructure of the bridge. The construction of this bridge and several other similar prestressed concrete bridges are described herein. The existing condition of eleven prestressed concrete bridges remaining in Tennessee is given. Only minor spalling, leaching, and horizontal cracking are present in the superstructure after fifty years of service. Many of the design features introduced in this design can be found in today’s modern precast segmental concrete bridges.  相似文献   

15.
A bridge across the Hudson River opposite Manhattan Island was a dream that started in the early 19th century. Many giants of civil engineering, including Gustav Lindenthal and Othmar Ammann, were involved in planning such a bridge but it was not until 1931 that Ammann’s George Washington Bridge crossed the river. This paper covers the period from 1805 to 1935.  相似文献   

16.
This paper presents experimental investigations on Bailey bridges. Seven one-sixth scale models of the Bailey bridge trussed-steel frame were constructed in the laboratory and tested. All members of the scale models of steel frames are solid rectangular sections. Both ends of the members are fully welded. Some members of three selected specimens were removed to study their effects on degradation of limit loads. The cross-section areas of some members in two of the specimens were reduced to simulate the phenomenon of member corrosion. Two numerical methods, second-order elastic and inelastic analyses are used to predict the behavior of the steel frames. The responses determined by numerical methods are compared with test results. The scale model without lateral bracing members collapsed in the global lateral buckling mode at a very small limit load. The lateral bracing system of a planar frame is very important for preventing an early collapse and allows the ultimate strength to be reached.  相似文献   

17.
This paper provides a summary of the major research studies conducted or being conducted in the U.S., to address design issues related to use of high performance steel (HPS) in bridge construction. Emphasis of the paper is on the work related to HPS-485W steel, which has specified minimum yield strength of 485 MPa (70 ksi). Design issues that are addressed in this paper include (1) flexural capacity of compact and noncompact HPS sections in negative bending; (2) issues related to ductility of HPS composite girders in the positive sections (this section presents a simplified ductility check for composite plate girders); (3) tensile ductility of HPS plates; (4) shear capacity of the hybrid steel plate girders; (5) live load deflections; and (6) brief overview of the work that is underway to develop innovative bridge configurations capable of incorporating the advantages of HPS.  相似文献   

18.
The damage suffered by elevated viaducts of the Hanshin Expressway Kobe Route during the 1995 Kobe earthquake is described with emphasis on reinforced concrete (RC) piers. Although many piers were severely damaged, it is also true that the damage to many piers appeared moderate or even mild. On the other hand, a number of piers suffered from large residual inclination in spite of the apparently light damage. By considering that the large residual inclination of piers included severe earthquake-induced damage, it is pointed out that almost all the RC single piers from P35 to P350 received consistently severe damage. The cause of large residual inclination, especially in apparently nondamaged piers, is studied. A dynamic analysis of a single RC pier is conducted to study the relationship between residual inclination and residual deformation of a pier. As a result, we find that the flexural residual deformation of a pier cannot explain the observed large residual inclination, but it is suggested that the pulling out of reinforcing bar from the footing can be a primary cause of the observed large residual inclination.  相似文献   

19.
Almost all the single reinforced concrete (RC) piers from P35 to P350 received consistently severe damage, considering the large residual inclination of piers included in earthquake-induced severe damage. However, some of the piers in the section from P35 to P350 remained lightly damaged, and this phenomenon is observed especially in many piers under fixed bearings in continuous girder bridges. In this study, using experimentally based models for metal bearings and installing them to an existing FEM code, a nonlinear dynamic response analysis of a continuous girder bridge system is conducted. It is shown that the results depend on the ground motion, but the fuse effect of the breaking of the bearings could have been a reason for the phenomenon.  相似文献   

20.
The chemical constituents of essential oil from the pericarp of Illicium modestum were analyzed and 60 compounds were identified by GC-MS. Among them anethole (main compound in the oil of Chinese anise star) and safrole were absent.  相似文献   

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