Main Arch Ring Research Articles

Analysis of the Temperature Effect During the Lifting Stage of The Main Arch Ring of The Strong Skeleton

In this paper, a finite element model of the main arch ring of the strong skeleton is developed in order to analyse the stress and deflection response of the strong skeleton under the action of uniform temperature during the lifting stage. Uniform temperature action was found to have a significant effect on the stresses and deflections of rigid skeletal stringers. The effect of the huddle on the stress and deflection of the skeleton at the non-design reference temperature was further investigated, and the results showed that the changes of the stress and deflection of the skeleton were directly proportional to the relative temperature difference (the difference between the huddle temperature and the design reference temperature).In addition, a reasonable value for the jointing temperature was analysed, and it was suggested that a value of 2℃slightly lower than the average annual temperature be used as the jointing temperature.

Simulation analysis of the entire construction process of the sunflower shaped continuous arch bridge

At present, there is a lot of research on the structural system of the completion stage of the Kuihua arch bridge in China, but there is a lack of research on the risks existing in each stage of the construction of the Kuihua arch bridge. Therefore, it is necessary to conduct a full process simulation analysis of the construction process of the sunflower shaped continuous arch bridge. The following conclusions were drawn from this study: (1) After analysis, the construction method of first removing the support below the main arch ring and then pouring the main beam can ensure the safety of construction. (2) The maximum axial force of the support pole below the main arch is -17.67kN, located in rows 10 and 50. The maximum vertical displacement of the main arch is -4.998mm, which is much smaller than the allowable deflection. Therefore, the shape of the main arch is within the safe range. (3) The tensile stress of the main arch and continuous longitudinal beam are both less than the design value of C40 concrete tensile strength of 1.71MPa, so the main arch and continuous longitudinal beam have not cracked, and are in a safe state throughout the construction process.

Evolution Law of Concrete Interface Stress of Rigid-Frame Arch under Construction and Its Impact on Ultimate Load-Bearing Capacity.

To study the evolution of stress on the ring and segment interfaces during the construction process of the concrete encapsulation of the main arch ring in a rigid-frame arch bridge, alongside its impact on the ultimate load-bearing capacity of the main arch ring, a 1:10 scale model experiment was conducted by taking the 600 m Tian'e Longtan Bridge as the prototype. The key cross-section concrete strain data were collected during the entire construction process of the main arch ring via fiber-optic strain sensors, which were used to investigate the stress evolution at ring and segment interfaces. ANSYS APDL was employed to simulate the ultimate bearing capacity under various loading conditions of two different finite element models, which were, respectively, formed segmentally and by single pouring. The results revealed that (1) after the closure of the concrete encapsulation of the main arch ring, the concrete stress in the cross-section exhibits significant stress disparities. At the same cross-section, the level of the web concrete stress can reach 76% of the floor concrete stress, while the roof concrete stress level is less than 20% of the floor concrete stress. (2) At the junction of two adjacent work planes, there are considerable differences in the stress levels of the concrete on both sides. After the closure of the main arch ring, the intersegment stress ratios of the floor, web, and roof concrete are 60~70%, 40~60%, and 0~5%, respectively. (3) Loading conditions remarkably affected the ultimate bearing capacity of the main arch ring. Under mid-span loading and 1/4 span symmetrical loading conditions, compared to single-pour concrete encapsulation, the ultimate bearing capacity of the main arch ring with concrete encapsulated by segmented and ring-divided pouring decreased by 19.16% and 5.23%, respectively, compared to single-pour concrete encapsulation. This suggests that the non-uniformity of stress distribution in the concrete sheath can lead to reductions in the ultimate bearing capacity of the arch ring.

Research on Loading Scheme for Large-Scale Model Tests of Super-Long-Span Arch Bridge

A reasonable and efficient loading scheme is needed to guarantee the success of large-scale bridge tests. In this study, an array-type, self-balancing pulley-group loading system was designed based on the world’s largest spanning arch bridge using a 1:10 scale model test. Automatic statistics of the required load at each loading point were realized using ANSYS, and a load optimization algorithm for loading points at different construction stages was proposed. Tests were carried out separately for the loading system using a single set of pulley groups and an array-type pulley group. Finite element models of the model bridge and the original bridge were established separately using ANSYS, and the stress results of different components during different construction stages of the main arch ring were compared. The research results show the following: (1) The load magnification factor of the single-pulley-group loading device is approximately 6.6 times, with a mechanical efficiency of 94.26%. (2) In the array-type loading system, the actual load at each loading point can reach the design value. The self-balancing characteristic of this system can eliminate the impact of vertical deformation of the structure on loading accuracy, verifying the reliability of the system. (3) The simulation results of the original bridge and the model bridge coincide well, and the stress of each component during the construction process has the same trend. At key construction stages, the maximum relative errors of the stress results of the rigid steel frame and the concrete inside the pipe of the two bridges are 8.33% and 9.34%, respectively, and the maximum absolute error of the bottom plate concrete is 0.66 MPa, verifying the correctness of the counterweight-optimization method. The loading scheme proposed in this paper can provide a reference for the design of loading systems with the same type of scale model test.

Analysis of Seismic Response of the Arch Bridge across Reservoir considering Fluid-Solid Coupling Effect

Most of the deep-water bridges in Chinese reservoirs are concentrated on rivers in the southwest region. The unique structural characteristics of arch bridges are more in line with the geological topography requirements of deep reservoir areas, making them the bridge type of choice for bridges in deep reservoir areas. While the southwest region is an earthquake-prone area, in order to study the safety of arch bridges across deep water in the reservoir area, it is necessary to analyze the effect of water under seismic behavior on the box section arch ring and explore the effect of arch inundation depth on the dynamic response of arch bridges in the reservoir area. In this study, the effect of fluid-solid coupling is considered, the modified Morison equation is used to calculate the hydrodynamic pressure, and the effect of arch bridge inundation depth on the dynamic response is analyzed based on the Midas/civil finite element model of the arch bridge in the Yunnan reservoir area. The results show that the seismic response of the arch bridge across the reservoir is greatly influenced by the submergence depth of the arch bridge due to the fluid-solid coupling effect, and the influence of the hydrodynamic pressure on the longitudinal moment (My) and transverse moment (Mz) of the arch bridge increases with the increase of the submergence depth. There is a threshold value of the submergence depth. When the submergence depth is less than the threshold, the effect of fluid-solid coupling is negligible, and when the submergence depth is greater than the threshold, the fluid-solid coupling effect is significant. The thresholds for different parts of the main arch ring are different. The most unfavorable water depth in different parts of the main arch ring is not necessarily the water depth when the arch ring is completely submerged. Based on this result, for reservoir arch bridges in high intensity areas, it is recommended that the inundation depth of arch bridges crossing deep water reservoirs should be h/f less than or equal to 5/8 f.

Research on the Method of Temporary Prestressing to Regulate the Stress in the Section during the Construction of the Main Arch Ring of the Cantilever Cast Arch Bridge

To control the level of tensile stress in the section of reinforced concrete arch cantilever construction, a construction control method of temporary prestressing reinforcement is proposed in this study. The influence law of temporary prestressing on the arch ring section stress is revealed based on the engineering background (Shatuo Special Bridge in Guizhou). Meanwhile, a temporary prestressing test is carried out on the ring section of the main arch to verify the effectiveness of the method. The results show that the prestressing configuration during the construction of the main arch ring of the suspension arch bridge has obvious influence on the control of tensile stress. The method can also effectively improve the force uniformity of the buckle cables, reduce the variation range of cable forces during construction, and improve the safety of arch ring construction.

Elastic-plastic time-history analysis of steel-tube stiff-frame arch bridge without inner filling concrete

Based on a case study of a typical arch bridge with hollow steel tube and stiffness frame located in the high intensity region of western China, this paper adopts the onlinear time- history method to analyze the structural response of the overall bridge elastic-plastic model under seismic action. Under the force of Wolong wave in Wenchuan Earthquake, the main load-bearing members of the structure have a good seismic performance. Only part of the columns on the main arch ring enter the plastic hinge state for energy dissipation, and the lower columns have a more obvious energy dissipation effect than the higher ones. The result indicates that the design idea of structure which is similar to that of strong column and weak beam in ductility design, has the characteristics of “strong arch and weak beam” and can therefore improve the ability of structure to resist collapse under earthquake action.

Evaluation of bearing capacity of reinforced stone arch bridge based on static load test

In order to evaluate the stress and working performance of a reinforced stone arch bridge, the load test of the bridge is carried out. Static load test is to test the stress and displacement of each section of the main arch ring under the action of partial load and medium load. The results show that under the action of various loads, the check coefficients of deflection and strain of this bridge do not exceed the specification limit of 1.0 of masonry arch bridge, the actual working performance of the structure is good, the maximum value of relative residual strain and relative residual deformation are 11.11% and 8.21% respectively, and they do not exceed the standard allowable value of 20%, and the whole bridge is in the elastic deformation stage. The test results show that the reinforcement method of thickening the main arch ring has good application value, can effectively improve the service level of the old bridge and prolong the safety service life, and has obvious social and economic benefits.

Evaluation of bearing capacity of reinforced stone arch bridge based on dynamic load test

In order to evaluate the stress and working performance of a reinforced stone arch bridge, the load test of the bridge is carried out. Dynamic load test is used to test the inherent fundamental frequency, damping ratio and impact coefficient of the bridge through pulsation test and sports car test. Under the dynamic load, the first vertical natural vibration frequency of the bridge is 5.005, the damping ratio is 0.203, the second vertical natural vibration frequency of the bridge is 6.274, the damping ratio is 0.021, the tested strain impact coefficient is between 1.03 and 1.10, the measured vertical fundamental frequency is greater than the calculated fundamental frequency, and the overall stiffness of the bridge meets the design specification. The test results show that the reinforcement method of thickening the main arch ring has good application value, can effectively improve the service level of the old bridge and prolong the safety service life, and has obvious social and economic benefits.

Investigation and finite element simulation analysis on collapse accident of Heyuan Dongjiang Bridge

The collapse accident of Heyuan Dongjiang Bridge was studied through site investigation, analysis of collapse videos, finite element simulation inversion analysis and other methods. Firstly, photos and videos regarding the collapse site were collected to analyze the possible causes of the collapse. Secondly, the three-dimensional FEM of Heyuan Dongjiang Bridge were established based on the information and videos of the collapse. Thirdly, the collapse process of Heyuan Dongjiang Bridge was inversely analyzed based on the finite element model (FEM); finally, the site data, collapse videos and finite element simulation results were combined to comprehensively analyze the causes for the collapse of Heyuan Dongjiang Bridge. The results showed: the performance degradation of main arch ring’s material and the foundation displacement were the major causes of the collapse of Heyuan Dongjiang Bridge. Accordingly, it was recommended to test and evaluate the performance of the main arch ring materials of deck type arch bridges on service for a long time; and check the displacement of the piers (abutment) in segments of rushing water.

Study on Dynamic Response of Arch Bridge under Vehicle Braking Based on Model Updating

In view of the insufficiency of the current research on special driving, this paper modifies the finite element model based on the static and dynamic measured data, and obtains the benchmark model reflecting the true state of the actual stress state. The influence of braking position and deceleration on key components of arch bridge is studied by establishing the vehicle-bridge coupling model under braking action and choosing three axles to load. The results show that the braking force of vehicle has a great influence on the dynamic response of key parts of arch bridge, and increases with the increase of braking deceleration. At the same time, the influence of vehicle braking force on the arch bridge column is obviously greater than that on the main arch ring.

Research on the Mechanical Characteristics of Long Span Cantilever Casting Deck Arch Bridge

In order to study the mechanical characteristics of long span cantilever casting deck arch bridge, taking Jiashi super-large bridge with 225m main span as an example, and the finite element software Midas civil is used to analyze the mechanical characteristics of the completion state of the bridge and the changes of the internal force in each construction stage. The results show that the internal force at each segment of the arch ring is small and uniform when the closing segment of long span cantilever casting deck arch bridge is constructed, which can make the closing operation of the main arch ring safely and smoothly. What’s more, the internal force at the arch feet and vault of the main arch ring is large when the bridge is completed, while the internal force at the two construction segments adjacent to the vault is larger than that at the vault which needs to be paid more attention.

桥面空心板安装阶段主拱圈稳定性研究

桥面空心板安装阶段主拱圈稳定性研究

Construction Simulation Analysis of 60m-span Concrete Filled Steel Tube arch bridge

The construction process of the CFST arch bridge is complicated. The construction process not only affects the structural stress in the installation, but also determines the form a bridge and internal force of the bridge. In this paper, a 60m span concrete filled steel tube tied arch bridge is taken as the background, and a three-dimensional finite element simulation model is established by using the MIDAS/Civil bridge structure analysis software. The elevation of the main arch ring, the beam stress, the forces in hanger rods and the modal frequency of the main arch during the construction stage are calculated, and the construction process is simulated and analyzed. Effectively and reasonably guide the construction and ensure that the line and force conditions of the completed bridge meet the design requirements and provides a reliable technical guarantee for the safe construction of the bridge.

The Detection Evaluation and Reinforcement Research of Kankan River Bridge

This design is about Chongqing Wanzhou district KanKan river crossing test evaluation and reinforcement renovation. The bridge is an open spandrel stone arch bridge. After years of operating, defects arise from different parts. To verify whether the bridge meets the bearing capacity of highway grade I standard, this design firstly evaluates the bridge through the apparent diseases. Then it uses Midas/Civil to calculate the bearing capacity of lateral control section for Zhou Jiaba arch foot, L/4 and arch section. Using Midas/Civil control section load calculation, load test plan is made. In the end, by increasing cross-section method, the bridge reinforcement maintenance plan is made; that is increasing abdominal 26 cm concrete layer in the main arch ring of arch so that the bridge meets grade I highway capacity requirements.

Evaluation on Risk for Ship Collision with Archbridge and Crash Capability of Anti-Collision

The development of the highway traffic has promoted the construction of increasing numbers of river-crossing bridges, but at the same time, large-size ship causes serious threat to structural safety of the bridge. The probability of bridge-ship collision increases, water safety accidents have happened frequently in the recent years. Arch bridge is easier to be subjected to the threat of ship collision because of small navigation clearance on both sides. However, study on the destructive consequences by ship impact on arch bridge is seldom. This paper takes reinforced concrete arch bridge as an example, on the basis of the forecast of the water-level frequency, flow velocity and long-term navigation density of the ship, the ship collision probability on different parts of the arch ring at different water levels are analyzed to deduce the annual collapse frequency of the grand bridge. The risk matrix evaluation result shows that there is medium risk in long-term. The establishment of finite element numerical model concludes the energy absorption and the change process when the arch ring suffers from collision from the ship under different working conditions as well as the relationship among the impact force, crown displacement and collision depth along with time change. According to the result of simulated analysis, the maximum collision force of the main arch ring suffered from the ship is 25.9MN, and the resistance of the main arch ring is 33.6 MN, so the existing structure basically meets the requirement for fortification against the ship collision. The numerical simulation results are qualitatively consistent with the risk of evaluation. The results of the analysis can provide scientific foundation to the maintenance and management of the arch bridge.

Analysis and Evaluation on Safety of Old Stone Arch Bridge Based on Current Specification

This paper examines the bearing capacity and stability of a catenary axis uniform cross-section multi-span stone arch bridge with solid spandrels in the cold areas. Taking the West Ulanhot Large Bridge built in cold area of Inner Mongolia in 1960s as an example, the bearing capacity and stability of early-built stone arch bridge were calculated,in consideration with the effect of dead load, live load and temperature variation as well as multi-arch action on the main arch ring, in the light of current specification, i.e., the Code for Design of Highway Masonry Bridges and Culverts (JTG D61-2005) published by the Ministry of Communications of the People's Republic of China. The aim was to evaluate the safety of the old multi-span arch bridge through the theoretical analysis and checking calculation based on the current specification.

Dynamic Response of Concrete Arch Bridge under Blast Loading

In order to reduce loss of terrorist attacks or accidental explosion accidents to traffic facilities of the state and society, antiknock safety of long-span bridge needs to be further studied. A deck arch bridge calculation model of fluid-structure interaction was established, and explicit dynamic analysis was presented to study the dynamic response of long-span arch bridge under blast loading, and the explosion effect to the overall structure of the bridge was analysed. The results show that the area around explosion center, has local large deformation and heavy damage degree, while a little far region has low deformation and damage degree; When explosives is located on the deck, the damage of blast-impact load on the main arch ring can be neglected, which is advantageous to the late bridge repair work. The results of this article can be provided as important theoretical reference to antiknock and explosion-proof of bridges in the future work.

Research on Masonry Arch-Bridges Reinforcement and Reconstruction Methods

We analyze existing masonry arch-bridges and corresponding reinforcement methods in this paper and bring about the method of using strip-shaped outer-wrap reinforced concrete with chemically planted bar to improve the new and old concretes cooperative work so as to strengthen the wholeness and improve impermeability of the bridge. We also compare two experiments on one actual bridge of 30 cm strip-shaped outer-wrap reinforced concrete in the main arch ring and 20 cm global outer-wrap reinforcement concrete, of which the data shows the superiority of strip-shaped outer-wrap reinforced concrete for it strengthens both the bridge floor and bottom structure and improve the load capacity.

Behaviour Analysis of Prestressed Concrete Deck-Tied Arch Bridge

The prestressed concrete deck-tied arch bridge doesn’t only have a long span, good appearance and economy, but also have the characteristics of low requirements to the foundation. It changes traditional tied arch bridge into deck-tied arch bridge, which looks like sunflower-shaped arch and prestressed steel strands are embedded in box girder on the top of the arch. Taking Yingbin Bridge as engineering background, the reasonable analysis model was established and behaviour of the bridge under design load was analyzed. The results shown that the design project is reasonable, prestressing force embedded in box girder can balance horizontal thrust in arch bridge effectively, improving the internal force of the main arch ring.