Applied Mechanics and Materials Vols. 178-181

Abstract: In order to research the influence of web’s shear deformation on the deflection of composite girder bridge with corrugated steel webs in construction, the deflection calculation formulae considering shear deformation were deduced, which was to analyze the background engineering of Chuhe bridge deflection in different load conditions when it was in the maximum cantilever state. Finite element method analysis shows that the calculation formulae are credible and applicable, and also comparative study was done with practical measurement. Results show that the proportion of main deflection caused by shear deformation of web may reach 30% ~ 40%, and the deflection caused by shear deformation needs to be considered in the process of construction monitering.

Abstract: Due to the role of the vehicle, the large-span bridge’s frequency which is according to the bridge monitoring data is actually the vibration frequency of the vehicle-bridge coupled vibration system, but not the bridge’s natural frequency. This paper gets formulation of the added mass and the beam’s natural frequency according to the added mass of the beam’s vibration equation; and the formulation is tested by experiments and numerical simulation of a large-span steel truss bridge model. Result shows that added masses which have the fixed location are linearly proportional to changing values of the bridge’s nature frequency.

Abstract: From the cable-stayed the basic linetype equations,the cable-stayed parameter of engineering application value are derived. The simplifed calculation method of cable-stayed based on origin of moving coordinate method are presented, and then the simple and practical calculation of cable-stayed form are developed using a single variable solve and macro commands of excel. Finally, by comparison shows that the method is correct.

Abstract: Directed toward the feature of distortion of concrete box girder bridge, the layered approach of analyzing distortion is put forward, displacement model and geometric equation are established by using the generalized coordinates principle, and the formula of distortion shear stress is derived, and then a analytical theory of distortion of thick-walled box girder is established based on the mixed variational principle. The numerical experiment indicate that it cannot be neglected that thick-walled effect of distortion of concrete box girder bridge and the predicted results by the new theory are accurate.

Abstract: In order to study the influence of beam-reduction and rib-addition strengthening method on the natural vibration properties of hollow slab bridges, based on bridge natural vibration frequency and the vibration mode in the first three orders as main comparison parameters, according to the comparison between the theoretical values as well as experimental values of the natural vibration properties before and after strengthening, the practical effect of this strengthening method is studied. The test data show that the beam-reduction and rib-addition strengthening method results in an obvious enhancement of the natural vibration frequency of simply supported hollow slab bridges, which proves that the strengthening method has remarkable improvement effect on the rigidity of bridges. It can be seen from the comparison of the changes of the vibration mode in the first three orders before and after strengthening that the transverse connection of bridge is strengthened and the integrity is prominently enhanced after strengthening. The study result is that the beam-reduction and rib-addition strengthening method can greatly enhance the structural behavior of hollow slab bridges.

Abstract: Based on the principle of thermal expansion and theory of virtual work, a class of equations for in-plane displacements at radial direction and internal forces in the cross-section of statically indeterminate curved beams under radial concentrated load are derived explicitly. In the case of infinite limit of radius, these equations coincide with that of the straight beams. Compared with the results of FEM, the analytical solutions by the proposed formulae are accurate. The analytical solutions obtained in this paper would provide a scientific base for further study and design of the curved bridges.

Abstract: The settlement of high cap extra-long large diameter pile groups is made up of pile elastic compression and settlement of soil layers under pile end in theory. Methods to calculate pile compression of high cap extra-long large diameter pile groups was deduced or listed. Six methods to calculate settlement of soil layers under pile end were expounded through extra-long large diameter pile groups under south tower of main bridge of Sutong Yangtse River Highway Bridges. The results show that piles’ elastic compression should be calculated into the settlement of extra-long large diameter pile groups, including that caused by pile’s own weight, and it is little difference between test value and total settlement which is composed of piles’ elastic compression calculated through the formula deduced in the paper and theoretic settlement of soil layers under pile end based on Mindlin’s additional stress solution, only making 0.06% lower.

Abstract: The whole length of Beiguan Bridge is 470m. Its main bridge, 40+118+40m long, is a Self-Anchored Reinforced Concrete Suspension Bridge. Taking the spot supervision of Beiguan Bridge for example, this paper mainly describes the experience of supervision for self-anchored reinforced concrete suspension bridge.

Abstract: Considering the slender property, the reinforcement is always simulated by linear element in conventional FEA of concrete structures. But to the curve prestressed reinforcement, it will lead to the problem that the calculated result of local stress distribution is greatly affected by element size, because of the tectonic stress concentration by the coupling between the linear element and body element. To eliminate the harmful effect, the curve prestressed reinforcement can be simulated by body element. The result shows that it will solve the problem thoroughly, and the calculated result is truthful and reliable. Certainly, as a kind of slender component, there are some key point must be recognized when the curve prestressed reinforcement is simulated by body element. To reflect the mechanical properties of prestressed reinforcement and solve the key challenges of modeling, some key techniques of modeling and some special notices about element property settings are discussed detailedly in this paper.

Abstract: Consideration of natural wind related features, improved use of the harmonic synthesis, along with a high degree of change Simiu spectrum and Lumley-Panofsky spectrum as the goal of full-bridge stochastic wind field were simulated, generating a bridge structure of discrete points of vertical and horizontal wind pulse of time. Carried on the simulation using large universal finite element ANSYS, and the overall evaluation structure’s geometry misalignment, the host cable bridge tower wind load, the effective wind angle of attack’s influence, has calculated of the beam self-excited forces and obtained the long-span and slender suspension bridge with steel truss stiffened girder buffeting response result.