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The shear lag of the box girder section of a wide box bowstring arch bridge was investigated in this study. The finite element analysis software Midas Civil was used to discretize the bridge into separate entities, establish its spatial model, and analyze the law of shear lag effect in the longitudinal direction during the main construction stage and the completion stage separately. The shear lag effect is more prominent at certain key points due to the influence of the tension of the boom and the weight of the arch foot during the construction stage. After the bridge is completed, the axial pressure of the arch foot drives the shear lag effect near the midpoint of the main girder section to its maximum; the axial force is transmitted along the longitudinal bridge direction in a V shape along which it gradually decreases. Under the action of uniformly distributed load, the cross-section of the box girder near the middle fulcrum is affected by the axial force of the arch foot; there is both a positive and negative shear lag effect. Under the eccentric load, the positive and negative shear lag effects appear simultaneously at the end fulcrum. The shear lag coefficient is higher in the web on the eccentric load side than the non-load side. There is obvious and widely fluctuating positive/negative shear lag effect in the vicinity of the middle fulcrum. There is significant tensile stress on the roof under the action of the middle fulcrum. The cross-sectional stress of a single-box seven-cell box girder under compression-bending load action was analyzed according to the finite element analysis results. The stress was decomposed into a superposition of bending moment action and axial force action. The shear lag coefficient λ M under the action of bending moment was also solved via energy variation method. Assuming that the axial force is only borne by the compressed area, the shear lag coefficient λ N under the action of the axial force was obtained; λ M and λ N were superimposed to determine the comprehensive shear lag effect coefficient λ .

The paper deals with the following magnetic Schrodinger equation with singular nonlinearity and steep potential $\left\{ \begin{array}{l} ( - \Delta )_A^su + {V_\lambda }(x)u = \mu f(x){u^{ - \gamma }} + g(x){u^{p - 1}},{\rm{in}}\;\;{{\mathbb{R}}^N},\\ u > 0,\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;{\rm{in}}\;\;{{\mathbb{R}}^N}, \end{array} \right.$ where $ (-\Delta)_A^{s} $ is the fractional magnetic Laplacian operator with $ 0 2s \right) $, the potential $ V_{\lambda}(x) = \lambda V^{+}(x)-V^{-}(x) $ with $ V^{\pm} = \max\{\pm V, 0\} $, $ \lambda, \mu>0 $ are parameters, $ f\in L^{\frac{p}{p+\gamma-1}}( \mathbb{R}^N) $ is a positive weight, while $ g\in L^{\infty}( \mathbb{R}^N) $ is a sign-changing function. By applying the Nehari manifold and fibering map, we obtain the existence of at least two positive solutions, where some new estimates will be established. Recent some results from the literature are extended.

With the development of the civil aviation market, how to improve the operating efficiency of airport taxis while ensuring a balanced income for drivers has become an important task. This paper recommends using a hybrid strategy model for analysis. It is analyzed, in this paper, the factors influencing the driver’s decisions to obtain the qualitative relationship between the driver’s income and costs such as time cost and no-load cost. We simplified the problems that are a game between driver groups whether or not to wait to establish a hybrid strategy model and to provide references in the selection of the two schemes for drivers. A scheme to give priority to short-distance passenger-carrying drivers is proposed. The two sides of the game are re-determined as short-distance passenger-carrying drivers and long-distance passenger-carrying drivers and income equilibrium of both parties are obtained. The results showed that under the new scheme, both parties have equal expectations of income so the new scheme is feasible.

Carbon fiber materials are widely used in bridge reinforcement techniques, while conventional carbon fiber material tensile anchoring equipment produces a large prestressed loss. This paper analyzes the deficiencies of existing tensile anchoring systems at home and abroad, summarizing the cause of prestressed losses, and combining with existing anchoring systems, a new type of clamp type carbon fiber cloth tension anchoring system is proposed. The amount of deformation of the anchoring system is reduced by about 20%, which in turn reduces the system prestress loss caused by the system deformation. The ABAQUS finite element analysis software is used to numerically simulate the thickness of the tension anchor system and the force of the fixture at different inclination angles. Compare the experimental measurement data, under consideration of the mechanical properties of the system, making errors, and installation convenient prerequisites, the mechanical properties of the system are optimal when the thickness of the fixed plate is 30mm and the clamp tilt angle is 5 °.

In this paper, a general Kolmogorov type predator–prey model is considered. Together with a constant-yield predator harvesting, the state dependent feedback control strategies which take into account the impulsive harvesting on predators as well as the impulsive stocking on the prey are incorporated in the process of population interactions. We firstly study the existence of an order-1 homoclinic cycle for the system. It is shown that an order-1 positive periodic solution bifurcates from the order-1 homoclinic cycle through a homoclinic bifurcation as the impulsive predator harvesting rate crosses some critical value. The uniqueness and stability of the order-1 positive periodic solution are derived by applying the geometry theory of differential equations and the method of successor function. Finally, some numerical examples are provided to illustrate the main results. These results indicate that careful management of resources and harvesting policies is required in the applied conservation and renewable resource contexts.

The hot in place recycling technology has the advantages of economy, environmental protection, high efficiency, so it becomes more and more popular. But the post evaluation of hot in place recycling technology lacks scientific system. By analyzing the pavement performance post evaluation index of hot in place recycling technology, the independent post evaluation system of hot in place recycling technology is established. Based on the characteristics of heat recovery, this paper studies the performance evaluation of hot in place recycling technology at home and abroad, and further studies the post-evaluation index of HIR pavement performance and establishes a relatively complete HIR road surface performance evaluation system.

This article builds a model of the actual engineering using Midas/Civil, and makes an analysis of the impact on the deformation and stress of the bridge of concrete shrinkage and creep. Midas/Civil software uses the shrinkage and creep formulas in the "highway reinforced concrete and prestressed concrete bridge and culvert design specifications (JTG D62-2004). First, through changing the two parameters of relative humidity and creep coefficient of the model in the shrinkage and creep formulas specified in JTG D62-2004 specification, it analyses the effects of the shrinkage and creep on bridge deformation. Second, in and without the consideration of shrinkage and creep, it makes simulation analysis of the internal forces of the bridge to determine the degree of the influence of shrinkage and creep on bridge stress. By contrasting the parameters under different conditions, it obtains that the linear influence of the different relative humidities on the bridge is 25% in maximum. The concrete shrinkage and creep may also exert a relative great impact on the internal forces of the whole bridge. The stress of the upper flange decreases 1.9 MPa at most and the lower decreases 3.81 MPa at most. Through making an analysis on the impact of changing parameters and considering the shrinkage and creep on the actual engineering model linear and internal force, the author obtained the conclusion of the rule in the influence on a continuous girder bridge under the action of concrete shrinkage and creep, which provides a direction for the design and construction of continuous girder bridge using prestressed concrete.

Lining crack is the main form of tunnel disease. Tunnel lining crack undermines the integrity of the tunnel structure and reduces the strength and stiffness of lining structure. Thus it influences the normal operation of tunnel. Through the detection of a highway tunnel lining appearance and by using the software Midas GTS to conduct numerical calculation for typical section of tunnel lining are used to analyze the influence factors of cracking of tunnel. At the same time through analyzing the cause of crack and combining the actual condition of the tunnel this paper puts forward the regulation scheme of pasting CFRP to expect it can have the essential reference for the similar project in the future.

A class of second order impulsive Hamiltonian systems are considered. By applying a local linking theorem, we establish the new criterion to guarantee that this impulsive Hamiltonian system has at least one nontrivial T-periodic solution under local superquadratic condition. This result generalizes and improves some existing results in the known literature.

During the cantilever construction stage, bridge galloping stability problem caused by wind load cannot be ignored because the structure stiffness is small. Thus, it is necessary to study galloping reliability assessment of long-span continuous rigid-frame bridge. Taking Beishan bridge as an example in the paper, the occurrence of galloping is firstly analyzed qualitatively by wind tunnel test. Then, with the galloping critical wind velocity determined by wind tunnel test as structure resistance and stochastic wind speed at the site of the bridge as load effect, an probability evaluation model for galloping reliability assessment of long-span continuous rigid-frame bridge is established based on the existing structure reliability theory. In the end, the galloping reliability assessment and parametric sensitivity for Beishan bridge are given.