Thomas C. Clarke, Bridge Builder

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.     

Cabin John Bridge: Role of Alfred L. Rives, C.E.

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.     

C. Shaler Smith

Smith was one of the premier bridge builders of the post-Civil War period. He started his bridge building career under Albert Fink on the Louisville and Nashville Railroad. During the Civil War, he designed and built a powder factory for the Confederacy at Augusta, Ga. After the war, he formed Smith and Latrobe Co. and later The Baltimore Bridge Company with Benjamin and C. H. Latrobe. He worked closely with James Eads on the St. Louis Bridge and designed and built the long iron easterly approach to the bridge. He designed and built some of the major viaducts, swing, and fixed span bridges in the United States, Australia, and Peru, and finally innovative cantilever bridges over the Kentucky, Mississippi, and St. Lawrence Rivers.     

Kentucky River High Bridge

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.     

Squire Whipple—Father of Iron Bridges

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.     

George Shattuck Morison and the Development of Bridge Engineering

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.     

Niagara Cantilever

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.     

Joseph B. Strauss, Charles A. Ellis, and the Golden Gate Bridge: Justice at Last

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.     

Poughkeepsie Bridge: Its Birth, Abandonment, and Rebirth

When opened the Poughkeepsie Bridge incorporated the longest span—548 ft—cantilever in the world; the longest simple span, 525 ft; and its overall length, 6,767 ft, was for a short time the longest bridge in the world. Between 1871 and 1889, its opening, some of the leading engineers and railroad men had been involved in its planning and design including three future presidents of ASCE. Construction is currently under way to convert the bridge to a pedestrian/bicycle pathway across the Hudson River.     

Dynamic Stress Analysis of Long Suspension Bridges under Wind, Railway, and Highway Loadings

Computation of the dynamic stress of long suspension bridges under multiloadings is essential for either the strength or fatigue assessment of the bridge. This paper presents a framework for dynamic stress analysis of long suspension bridges under wind, railway, and highway loadings. The bridge, trains, and road vehicles are respectively modeled using the finite-element method (FEM). The connections between the bridge and trains and between the bridge and road vehicles are respectively considered in terms of wheel-rail and tire-road surface contact conditions. The spatial distributions of both buffeting forces and self-excited forces over the bridge deck surface are considered. The Tsing Ma suspension bridge and the field measurement data recorded by a wind and structural health monitoring system (WASHMS) installed in the bridge are utilized as a case study to examine the proposed framework. The information on the concerned loadings measured by the WASHMS is taken as inputs for the computation simulation, and the computed stress responses are compared with the measured ones. The results show that running trains play a predominant role in bridge stress responses compared with running road vehicles and fluctuating wind loading.     

Performance of a Tied-Arch Reinforced Concrete Railway Bridge: Rating, Safety Assessment, and Bond Length Evaluation

This study presents investigations regarding visual inspection, dynamic testing, and finite-element modeling of an approximately 80-year old reinforced concrete tied-arch railway bridge that is still in service in Turkey. Investigations were conducted as part of a systematic periodic inspection along Ankara-Zonguldak railway line. The bridge is subject to heavy freight trains with increasing axle loads. Field tests such as material tests and dynamic tests were used to calibrate the finite-element model of the bridge. Detailed information regarding testing and model updating procedure is given. Based on test results, computer model was refined. The calibrated model of the bridge structure was then used for structural assessment and evaluation. Despite sufficient overall safety, local details were found to be problematic. Due to insufficient bond length in hanger-to-arch connection, a strengthening scheme using steel channel sections was proposed.     

Natural Frequency of Railway Girder Bridges under Vehicle Loads

To investigate the natural frequency of a railway girder bridge under vehicle loads, two methods are presented. First, the natural frequency of a railway girder bridge under vehicle loads is obtained by solution of the eigenvalue of the vehicle-bridge interaction equation at each step of the numerical integration. Second, based on the vehicle-bridge interaction equation, an approximate formula is developed. The results show that the natural frequency of a railway girder bridge under vehicle loads varies periodically as the vehicles pass over the bridge. The results obtained with the two methods are then compared, showing that a good agreement is achieved. From parametric studies, the effects of the unsprung mass, the sprung mass, and the stiffness of the vehicle suspension are discussed.     

Vibration Control of Railway Bridges under High-Speed Trains Using Multiple Tuned Mass Dampers

In this paper, multiple tuned mass dampers (MTMDs) are considered for suppressing the vibration of railway bridges under high-speed trains. The interaction equations of motion between the vehicle and the bridge with MTMDs have been developed. The effectiveness of MTMDs on suppressing resonant vibration of railway bridges is examined and the optimum parameters of MTMDs for suppressing the resonant vibration are proposed. The results indicate that the use of the MTMD with the optimum parameters reduces the displacement and acceleration responses of railway bridges significantly.     

Investigation of Longitudinal Forces in a Concrete Railroad Trestle

Transportation Technology Center, Inc., the University of Illinois, and the Burlington Northern Santa Fe (BNSF) Railway Company conducted tests on a long concrete trestle to quantify the longitudinal forces generated by a coal train with AC locomotives. Results support the American Railway Engineering and Maintenance of Way Association (AREMA) formula for forces due to traction. Testing determined the distribution of shear forces in bents and the equilibrium of the structure in conjunction with an analytical model of the bridge structure. Design longitudinal forces and stresses in piles were also evaluated. The primary observation was that a large amount of longitudinal force is transmitted to the trestle, but it is distributed to a large number of bents through many spans. Forces in individual bents are quite small as compared to the total applied force.     

Seismic Retrofit of Hollow Rectangular Bridge Columns

The seismic performance of rectangular hollow bridge columns is a significant issue of the high-speed rail project in Taiwan. The flexural ductility and shear capacity of such columns with the configuration of lateral reinforcement used in Taiwan have been studied recently. This paper reports that hollow rectangular bridge columns retrofitted with fiber-reinforced polymer (FRP) sheets were tested under a constant axial load and a cyclically reversed horizontal load to investigate their seismic behavior, including flexural ductility, dissipated energy, and shear capacity. An analytical model was also developed to predict the moment-curvature curve of sections and the load-displacement relationship of columns. Based on the test results, the seismic behavior of such columns will be presented. The test results were also compared to the proposed analytical model. It was found that the ductility factors of the tested piers are in the range from 3.4 to 6.3, and the proposed analytical model can predict the load-displacement relationship of such columns with acceptable accuracy. All in all, FRP sheets can effectively improve both the ductility factor and shear capacity of hollow rectangular bridge columns.     

Dynamic Analysis of Metallic Arch Railway Bridge

This work describes some of the most interesting aspects of the experimental and numerical dynamic analyses of the Luiz I Bridge, an old arch double-deck iron bridge, when subjected to the moving loads of the new light metro of Porto. Presented are the methodology and computational tools developed, as well as some of the most significant results obtained from numerical simulations conducted on the basis of an experimentally calibrated finite-element model, both in terms of structural safety and of the comfort of pedestrians and train passengers.     

Charles Macdonald

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.     

50-Year-Old Prestressed Segmental Concrete Bridges

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.     

Bridge Inspection Practice: Two Different North American Railways

The purpose of this paper is to illustrate the bridge inspection philosophy of two different large railways. North American railways are primarily public investor owned businesses and must show adequate financial returns to survive. Also, without adequate financial returns it is very difficult to secure the funding necessary to adequately maintain structures and provide the service to customers that generates sufficient profit. The bridge inspection criteria are based primarily on ensuring a safe and reliable operation, an appropriate response, and the information with which to provide adequate funding for maintenance and replacement. Two different railway company philosophies are described. Of interest to the highway bridge community is how traffic volumes and structure load capacity influence inspection frequency and level of inspection. Items similar to Federal Highway Administration bridge inspection criteria are not discussed.     

Probabilistic Fatigue Evaluation of Riveted Railway Bridges

A probabilistic fatigue assessment methodology for riveted railway bridges is presented. The methodology is applied to a typical, short-span, riveted U.K. railway bridge under historical and present day train loading. On the loading side, the problem is randomized through dynamic amplification and traffic volume; on the resistance side, the S-N curves and the cumulative damage model are treated probabilistically. Model uncertainty is represented by the ratio between actual and calculated stresses, the latter obtained through finite element analysis. Annual response spectra for a fatigue-critical connection are developed through Monte Carlo simulation, which show that there is a continual and accelerating increase in the mean stress range experienced by the connection with time. S-N curves proposed in United States and United Kingdom codes are used in combination with Miner’s rule, to estimate the remaining fatigue life of the connection for different target failure probabilities. Parametric studies revealed that fatigue life estimates exhibit the highest sensitivity to detail classification, to S-N predictions in the region of high endurances, and to model uncertainty. This highlights the importance of field monitoring for old bridges approaching the end of their useful life.