Abstract: The precise evaluation and mitigation of the electric field generated by overhead transmission lines has gained great interest due to its impact on health and environmental issues. This paper presents a more generalized technique to calculate the electric field generated by power transmission lines in three dimension coordinates. This technique has been evolved, formulated, and applied to an Egyptian 500-kV single-circuit transmission line to evaluate the effects of line topology and terrain topography on the computed electric field. The results are compared with those produced by a 2-D technique.

Abstract: Based on the distributed fiber optic sensing technique of pulse-prepump Brillouin Optical Time Domain Analysis, this paper proposes an improved conjugated beam method (ICBM) for distributed structural deformation monitoring. Because ICBM is suitable for the combined actions of loads, support settlements and temperature variations, it extends the application of the classical conjugated beam method. Other advantages include the linear and explicit relationship between structural deformation and strain and the fact that all calculation parameters can be easily determined free from random load or section stiffness distribution. Theoretical and experimental investigations are carried out to confirm that the accuracy of deformation monitoring with ICBM in one span of a continuous structure is related only to the accuracy of strain measurements for the same span. This characteristic is used to avoid the influence of strain measurement error accumulation from a series of strain measurement data on other spans. Su...

Abstract: The updated finite element model of K??han Highway Bridge on the Flrat River located on the 51st km of Elazl-Malatya highway is obtained by using analytical and experimental results. The 2D and 3D finite element model of the bridge is created by using SAP2000 structural analyses software, and the dynamic characteristics of the bridge are determined analytically. The experimental measurements are carried out by Operational Modal Analysis Method under traffic induced vibrations and the dynamic characteristics are obtained experimentally. The vibration data are gathered from the both box girder and the deck of the bridge, separately. Due to the expansion joint in the middle of the bridge, special measurement points are selected when experimental test setups constitute. Measurement duration, frequency span and effective mode number are determined by considering similar studies in literature. The Peak Picking method in the frequency domain is used in the modal identification. At the end of the study, analytical and experimental dynamic characteristic are compared with each other and the finite element model of the bridge is updated by changing some uncertain parameters such as material properties and boundary conditions. Maximum differences between the natural frequencies are reduced from 10% to 2%, and a good agreement is found between natural frequencies and mode shapes after model updating.

Abstract: The invention relates to a large span steel box girder cable-stayed bridge tower lower beam segment mounting method, belonging to the bridge construction steel box girder construction technology field. The construction method comprises the steps: (1) setting up a masts type crane lifting tower area steel box girder by means of the upper crossbeam of the cable tower and the construction wind; (2) mounting the bridge deck crane in on the tower area steel box girder and lifting the first standard beam segment immediately adjacent to the tower area steel box girder; (3) mounting the bridge deck crane symmetrically on the mounted first standard beam segment, and starting the standard beam segment symmetrical hanging on both the river side and the bank side. The method in the invention achievesthe advantages of simple, practical, safe, reliable, economic, convenient less limited by the construction condition, solves the problems in present large span steel box girder cable-stayed bridge construction process.

Abstract: The invention discloses a preparation and on-board installation process of crane span of cutter suction dredger. The process comprises the following steps: preparing the jig of a crane span, performing sectionalized assembly of the crane span, performing wire-drawing to the trunnion of the crane span, performing wire-drawing to the trunnion of a hull, closing shipways, fixing the crane span, installing bolts, etc. The process of the invention has the advantages of convenient construction and good construction effect; and the installation time of the crane span is fully reduced, and the total cycle time for the preparation of ships is shortened.

Abstract: The paper investigates the applicability of current direct displacement based seismic design (DDBD) procedure, developed by Priestley and his coworkers, for straight long span bridges under transverse seismic excitation synchronous to all supports This category of bridges often possess some additional features such as massive tall piers, highly irregular distribution of mass and stiffness due to unequal superstructure spans and pier heights, large deformation capacity etc that are absent in short-to-moderate span bridges for which DDBD has extensively been verified It is shown that DDBD in its current form is unable to capture both displacement and base shear demand when compared with nonlinear dynamic analysis results Accordingly, a simple mechanics based extension of the current procedure that takes into account the effect of pier mass while computing base shear demand as well as a modal combination rule for estimating displacement demand is proposed and validated using a series of parametric studies The new procedure also allows engineer to allocate strength at the potential plastic hinge location in more general terms

Abstract: The invention relates to a space truss structure aerial pairing integral slide installation method, which belongs to the installation technical field of an aerial steel structure. The invention relates to an aerial space truss steel structure installation method. Scaffolds are arranged outside a house to pair a platform, after each pairing, the pair of platforms slide into the house, the splicing continues until all platforms slide in place, and slide rails are disassembled after supports are installed. The method has the advantages that the difficulty that the span of the space truss is large and no large-sized hoisting device exists on the spot can be solved; during the construction period of the roof space truss, the lower part of the civil work can be alternatively carried out; the expense for establishing the spliced platform is saved by 60 percent or more compared to an all-round scaffold aerial scattered installation method; and moreover, the peripheral land occupation of the building is less, and only one construction field is required.

Abstract: The invention discloses a large span rail traffic damage examination system in the computer applied technology field, which comprises a data acquisition subsystem and a data processing subsystem. The data acquisition subsystem is responsible to examine the vibration condition during a rail traffic vehicle crossing a large span bridge, and gathers dynamic response signals to transfer the data processing subsystem; the data processing subsystem reads the dynamic response signals of a bridge examined by the data acquisition subsystem, combines the dynamics to analyze and calculate the obtained bridge simulation dynamic response signals so as to realize the damage examination of the bridge, achieve that the operation of the system and the data management of the user through a graphic interface and a database technology, and realize the communication between a local computer and a remote computer through the network technology; the invention is characterized in that the invention is modularization and hierarchy, various functional modules can communicate with each other, the precision of the damage examination of the bridge is increased, the normal use of the bridge structure can not be affected.

Abstract: The paper presents the results and conclusions of dynamic load tests that were conducted on a road bridge over the Mokrzyca river in Wroclaw (Poland) made of galvanized corrugated steel plates (CSP). The critical speed magnitudes, velocity vibration, vibration frequency were determined in the paper. The dynamic analysis is extremely important, because such studies of soil-steel bridges in the range of dynamic loads are relatively seldom conducted. Conclusions drawn from the tests can be most helpful in the assessment of behaviour of this type of corrugated plate bridge with soil. In consideration of application of this type of structure in the case of small-to-medium span bridges, the conclusions from the research will not be yet generalized to all types of such solutions. The detailed reference to all type of such bridge structures would be requiring additional analysis (field tests and calculations) on the other types of soil-steel bridges.

Abstract: The utility model provides a self-anchored hybrid beam cable-stayed suspension cooperative system bridge, belonging to the field of building engineering technology, and particularly relates to a design of a large-span bridge in the bridge engineering The self-anchored hybrid beam cable-stayed suspension cooperative system bridge is characterized in that: after a cable tower and side hole piers are manufactured, a cantilever is assembled to a concrete main beam of the cable-stayed bridge, after the cantilever is assembled to side holes, main cables are suspended, two ends of each main cable are respectively anchored on an anchor block at the outer end of a concrete beam, the anchor block is pulled to a temporary anchoring structure via a temporary anchor cable; a suspension rod is suspended, and each section of steel main beam in the span is hoisted via a cable crane; after folding, temporary anchor cables are dismounted in batches, the main cables are completely anchored at the two ends of the concrete main beam, completing system conversion from temporary ground anchoring to self anchoring, completing bridge floor paving and rail construction, performing cable tension adjustment of full bridge, and forming bridge The effects and benefits of the self-anchored hybrid beam cable-stayed suspension cooperative system bridge are solving problems of design and construction of large-span bridges, reducing height of tower, full playing material performance, reducing construction cost, shortening construction period, and reducing risk in construction process

Abstract: Cross-winds of relatively low velocities have been observed over the years to cause large amplitude vortex-induced oscillations of the Rio-Niteroi bridge, the world's largest steel twin-box-girder bridge. These oscillations, which were recorded by the automatic long-term monitoring system and by video cameras installed on the bridge, revealed the existence of the lock-in phenomenon and hence the urgent need to attenuate the aeroelastic oscillations. To this end, a novel system of multiple synchronised dynamic attenuators has been installed in the central span of the bridge. A short account is given of how an experimentally calibrated mathematical–numerical model for the aeroelastic behaviour was used to assist in designing feasible mechanical control devices to upgrade the serviceability of this bridge and users' comfort. The conceptual design of the passive control system, together with its main geometric and physical characteristics, are briefly described herein. The efficiency of the control system is ...

Abstract: Reinforcement devices and systems for holding a traffic control assembly in compression are provided. The traffic control assembly includes a traffic signal disconnect hanger and/or a traffic signal and a first span wire positioned above the traffic control assembly. In some embodiments, the reinforcement device includes an upper support device connected to the first span wire where the upper support device has a length that is greater than a width of the traffic control assembly and the upper support device is configured to spread the load of the traffic signal assembly to the first span wire. The reinforcement device includes a lower support device operably connected to the traffic signal, a first vertical support member, and a second vertical support member where the first and second vertical members are tensioned when the upper support device, the lower support device and the first and second vertical support members are connected together.

Abstract: In comparison with the common two-tower suspension bridge, due to the lack of effective longitudinal restraint of the center tower, the three-tower suspension bridge becomes a structural system with greater flexibility, and more susceptible to the wind action. By taking a three-tower suspension bridge-the Taizhou Bridge over the Yangtze River with two main spans of 1080 m as example, effects of structural parameters including the cable sag to span ratio, the side to main span ratio, the deck`s dead load, the deck`s bearing system, longitudinal structural form of the center tower and the cable system on the aerodynamic stability of the bridge are investigated numerically by 3D nonlinear aerodynamic stability analysis, the favorable structural system of three-tower suspension bridge with good wind stability is discussed. The results show that good aerodynamic stability can be obtained for three-tower suspension bridge as the cable sag to span ratio is assumed ranging from 1/10 to 1/11, the central buckle are provided between main cables and the deck at midpoint of main spans, the longitudinal bending stiffness of the center tower is strengthened, and the spatial cable system or double cable system is employed.

Abstract: The invention provides a computing method of ice concentration of a transmission line The method comprises the following steps: the wire temperature and the elastic dependent variable in the fixed span of the transmission line are measured through a fiber grating measuring system; the total dependent variable in the fixed span of the transmission line is obtained according to the wire temperature and the elastic dependent variable; the wire specific load in the fixed span of the transmission line is obtained according to the total dependent variable and the wire specific load is compared with the wire self specific load in the fixed span of the transmission line; if the wire specific load is higher than the wire self specific load, the additional load in the fixed span of the transmission line is calculated; and the ice concentration in the fixed span of the transmission line is obtained according to the additional load The invention overcomes the problem of higher measuring result error caused by lower measuring accuracy and poorer anti-electromagnetic interference capability due to the adoption of an electric parameter measuring method for measuring stress, temperature and inclination angle in the prior art

Abstract: The paper deals with a new, arch road bridge made from structural corrugated plates, over the Plawna Stream, on a local road between Bystrzyca Klodzka and Ladek Zdroj in Stary Waliszow, Poland. The bridge replaced the old stone arch bridge that was destroyed during the flood of 1997. The steel bridge is founded on two continuous footings made of reinforced concrete. Its effective span is 10.00 m and its clear height is 4.02 m. The results of tests carried out on the bridge under three static load schemes after four years of service are presented. The average values of the measured displacements and strains in selected points and elements of the steel shell structure were found to be considerably lower than the ones calculated for the same load. Since designs of this type are more and more often adopted for small- and medium-size bridges, the conclusions drawn from the presented tests can be generalised to the whole class of such bridge structures.

Abstract: The utility model discloses a large-span steel girder for a straddle single-track traffic system, which aims to enlarge the span, facilitate the manufacture and the field splice, and reduce interferences with existing roads during the construction period. The large-span steel girder comprises two main beams (10) arranged in spacing across a bridge and adopting girders with box section structures;and the lower parts of the two main beams (10) are connected and integrated through a transverse bracing (20). The large-span steel girder has the benefits that by adopting the structural styles of straddle double main beams and vertical and horizontal connections, the span can reach 30 m to 80 m, and the segmental manufacture in a factory and the field splice are ensured. Furthermore, the large-span steel girder has the advantages of high material strength, light weights of segmental structures, convenient transportation, short field construction period, less interference with the existing roads, reliable quality, and the like.

Abstract: The invention discloses construction technology for a passenger railway line spanning existing railway cast-in-place box beam bracket, which belongs to the field of bridge engineering construction and is a construction technology method The method is used for solving the problem of building bracket when the bridge spanning existing railway is constructed The technology mainly solves the construction of a 48m-span spanning existing non-electrified trunk line railway in a newly-built passenger line railway (32 + 48 + 32)m continuous box beam in a form of setting up a (9 +21 + 9)m three-span Bailey bracket The technology can be applied to the engineering of spanning the existing double-line non-electrified trunk line railway on the cast-in-place bridge beam of which the span is about 48 meters, and can be used as reference for similar engineering

Abstract: The Nanjing Dashengguan Bridge is a key project on the Beijing-Shanghai high-speed railway; it is designed to handle a speed of 300 km/h. The main bridge has a large-span continuous steel arch truss structure with a total length of 1615 m. The two main spans over the main navigation channels of the Yangtze River are steel arch trusses, each of which is 336 m long. The arches comprise three truss planes above the orthotropic deck. Erection of the steel arch truss adopted the double cantilever method with auxiliary cables supported by towers on piers. (A)

Abstract: Span-to-depth ratio is an important bridge design parameter that affects structural behaviour, construction costs and aesthetics. A study of 86 constant-depth girders indicates that conventional ratios have not changed significantly since 1958. These conventional ratios are now questionable, because recently developed high-strength concrete has enhanced mechanical properties that allow for slenderer sections. Based on material consumption, cost, and aesthetics comparisons, the thesis determines optimal ratios of an 8-span highway viaduct constructed with high-strength concrete. Three bridge types are investigated: cast-in-place on falsework box-girder and solid slabs, and precast segmental span-byspan box-girder. Results demonstrate that total construction cost is relatively insensitive to span-todepth ratio over the following ranges of ratios: 10-35, 30-45, and 15-25 for the three bridge types respectively. This finding leads to greater freedom for aesthetic expressions because, compared to conventional values (i.e. 18-23, 22-39, and 16-19), higher ranges of ratios can now be selected without significant cost premiums.