Applied Mechanics and Materials Vols. 587-589

Abstract: A long-span cable-stayed arch bridge is a new form of bridge structure that combines features of cable-stayed bridges with characteristics of arch bridges. In the present study, we derived a practical calculation method for the lateral destabilization critical loading of cable-stayed arch bridges during the construction process based the energy principle. The validity of the method was verified with an example. The calculation method provides a quick and efficient way to evaluate the lateral stability of a cable-stayed arch bridge and a concrete filled steel tubular arch bridge during the construction process.

Abstract: This paper focuses on research of prestressed I-beams made of ultra-high performance concrete (UHPC), which are designed to be structural elements in small and medium span railway bridges. Prestressed concrete I-beams are designed with ten prestressing cables in the bottom flange. The prestressed beams are laid close together in the actual structure, with panels inserted between them. The entire structure will subsequently become monolithic. At the present time, I-beams made of rolled steel are commonly used as structural elements in this type of structure. The advantage of these types of structures lies in their having low construction height. This paper presents a computer and experimental analysis of loading of UHPC prestressed I-beams. For the purpose of the experiments, three specimens of 12 m span were made. The specimens were subsequently tested in the laboratory in four-point bending tests. The paper presents the process and results of the experiments. Simultaneously with the experiments, computer analyses were created in which optimization of the material and geometric parameters of the beams were carried out. The paper demonstrates the correspondence of the experimental and computer-simulated load test results.

Abstract: The object of this paper analyzes the reliability of half-through concrete-filled steel tubular arch bridges. Load and resistance parameters are treated as random variables. The statistical parameters are based on the available literature, test data and survey results. Reliability indices of main components of the bridge structure are calculated by iterations using the first-order second-moment method. The half-through concrete-filled steel tubular arch bridge is the typical series system and the reliability index of the system is calculated by the PNET method. The study shows that the reliability indices of suspenders are relatively larger than others, and the correlation coefficients among the same members have high relativity index.

Abstract: The subject investigated of this article is Maanshan Changjiang River Highway Bridge, which is a prestressed concrete cable-stayed bridge with three arched pylons. With the analysis of the details in design and construction of the main pylon of bridge, such as the set of the beams, the design of curve-shaped pylon and some significant parameters, it provide feasible experience in multi-pylon cable-stayed bridge. This article established the simplified finite element model with the software MIDAS/Civil and analyzed the load carrying capability and the deformation at the finished state of the bridge.

Abstract: In order to study the effect of guardrail to main girder, simply supported beam load test is relied on to measure the deflection of main girder in different conditions, then whether guardrails involved in the stress of main beam or not in theory is analyzed to draw the conclusion that considering the guardrail in stress is closer to the actual stress of bridge and effects on stiffness of main girder are different in lateral bridge. Based on above four hypotheses are proposed and the guardrail along the bridge transverse triangular distribution to the 14% deck is in good agreement with the actual situation according to the equivalent height.

Abstract: The Dissertation, relying on the construction of Zhanjiang Donghai Island Sea-crossing Bridge and adopting the finite element analysis method to calculate the wave force of substructure, proposes the bridge structure analysis method based on dynamic time history of wave loads. Through emulation analysis, structural load effect under waves is attained, making it a theoretically rational foundation for the structure selection and reinforcement of substructure of Donghai Island Bridge and having important theoretical significance and practical value in guaranteeing the bridge security under any seismic sea waves.

Abstract: Prestressed curved girder bridge is a important structure type in modem traffic engineering.With the development of economical level and situation of the opening in our country,a large lumber of curved girder bridge have been taken for its favorable linearism and good adjustability in any kinds of ground.This paper illustrates the working behavior of the prestressed curved girder bridge and use ABAQUS to analysis a simple prestressed curved girder bridge.

Abstract: The cables unstressed length is an important key parameter of design and construction control. In order to accurately calculate cables unstressed length for cable-stayed bridges, the longer principle for cables is avoided at current. The various factors were fully considered which affect cables unstressed length, and the sensitivity parameters of various factors were analyzed. The sensitivity factors were identified, and not sensitivity factors were ignored. It is sensitivity factors that towers deviation in advance, towers dynamic displacement, girders pre-camber, girders dynamic displacement, temperature difference, cables elastic modulus error, the load values with calculation of cables for elastic elongation. The accurately calculation method of cables unstressed length was proposed, which was based on sensitive factors. The method of cables unstressed length is more reasonable and accurate.

Abstract: The durability of coastal area bridge structures is more prominent, first, the understanding of the durability of the concrete is insufficient before, and the corresponding measures has not taken; Second, accelerating deterioration of the reinforced concrete is due to the environment and climate factors. Experience has shown that both home and abroad: Starting from the design, take preventive protection measures is effective means to improve the durability of reinforced concrete bridge,then it can get twice the result with half the effort. Based on the Tangshan Coastal Highway construction, considering of the leve of the engineering environmental and so on, on the basis of the service life of the bridge design, the durability of concrete structure would be studied.

Abstract: Taking a bridge of 160m long variable cross-section prestressed continuous curved box-girder as the research object and analyzing the cross-sectional design of axis with axial symmetrical or axial non-symmetrical to research the structure forces change of the upper part of bridge in different curvature. In order to test and verify the variable cross-section of prestressed continuous curved box-girder bridge is safe and reliable via cross-sectional design with axial symmetrical instead of axial non-symtrical within a radius of curvature of the interval. Creating the straight bridge and curved bridge models with different radius of curvature in same span by Midas/Civil to compare their structure forces.