Shallow landslides often occur in the vast majority of expansive soil cutting slopes during or after rainfall, resulting in newly-built highway traffic disruption, ecological environment destruction along roads, and high costs required for repair. The actual causes of shallow landslides are still unclear. Therefore, analyses of test data are used to study the attenuation law of the shear strength of expansive soil under the dry-wet cycle conditions. The shear strength of surface soil was found to have a nonlinear property resulting from the natural expansion soil. In addition, shallow landslides of expansive soil slopes in dry-wet cycles are analyzed. The serious attenuation of cohesion was found to be the main cause of shallow landslides in expansive soil slopes. Therefore, the measured nonlinear strength parameters of soil samples should be applied to analyze the stability of expansive soil slope, the results of which can be consistent with the calculation result of actual conditions.

To investigate the stress state and crack propagation of asphalt surface course bottom, the weight function of a rectangular plate with a single edge crack is derived based on weight function method. The I-II mixed-mode stress intensity factor (SIF), mixed-mode fracture criterion, and propagation law of crack in asphalt mixture, are studied based on the test model of pre-notched beam and three-point bending test of a single-edged notched beam. Results show the following findings:(1) Under the same load, with the notch close to the loading point, SIF and the maximum energy release rate of mode I increases while SIF and the fracture angle of mode II decrease. (2) The longer the notch is, the higher the maximum energy release rate becomes and the easier the beam cracks. (3) The mixed-mode cracking appears in the case of an asymmetric notch, and the initial cracking load increases with the increase of notch offset distance. Comparing these results shows that the weight function method exhibits precision in calculating the crack SIF of the beam.

For multi-feature fusion in automatic recognition of pavement distress images, we proposed a multi-feature fusion method based on manifold learning. In this method, the intrinsic features of pavement distress images are extracted through mapping the high dimensional data combing projection, mixture density factor and second order moment invariant into the low dimensional space. The multiple features are fused and the visualization of pavement distress images is implemented. In the experiments, we applied the multi-feature fusion method in the detection of pavement distress images. Two-dimensional features are firstly extracted from the 8 combining features, then the recognition effects on the 2D features of 4 methods including ELM, KNN, SVM and BP network are compared. The experiment result shows that the proposed method effectively improved the detection accuracy of pavement distress images. Simultaneously, the physical meaning of the 2D features is obtained through visualizing, one feature preliminary denotes the complexity and damaged extent of the cracks in images, the other describes the direction of the cracks.

The dynamic responses of different slope types are analyzed using the shaking table model test to study the influences of slope position and ground motion parameters on the dynamic response of acceleration. The influences of slope shape, elevation, seismic wave type, vibration intensity, and earthquake frequency on dynamic response are determined. The following conclusions are drawn from the experimental results. (1) The modal parameters of a slope are independent of elevation. The first-order natural frequency of the model system decreases gradually, whereas the damping ratio increases gradually as white noise increases slowly. (2) The acceleration amplification factor of a measuring point on a concave slope is slightly larger than that on a convex slope. The stability of a convex slope is better than that of a concave slope. (3) The elevation amplification effect, which is influenced by slope topography and ground motion parameters, differs under varying seismic loads. The elevation amplification effect of a concave slope is more significant than that of a convex slope. (4) The acceleration amplification coefficient obtained from each measuring point on the slope surface and in the inner region of the slope exhibits an increasing fold line trend. However, the acceleration amplification coefficient of each measuring point on the slope surface is greater than that in the inner region of the slope. (5) The slope dynamic amplification effect is closely related to the natural frequency of a slope. Within a certain range, when the frequency is high, the amplification effect is significant. (6) The influence of vibration strength on the slope dynamic response distribution is minimal along the height direction, whereas the influence on the slope acceleration amplification effect is evident.

The in-situ falling weight deflectometer (FWD) tests were conducted to develop a temperature correction method for asphalt pavement dynamic deflection. Results indicate that different values of temperature correction coefficient K were predicted by asphalt pavement static resilient deflection under JTG D50 and JTG E60 specifications, particularly at low temperatures. For asphalt pavement dynamic deflection, the JTG D50 method presented low precision, where as the JTG E60 method lacked an analytical formulation and displayed a limited valid layer thickness. A mathematical expression was developed for the temperature correction coefficient K on the basis of the falling weight deflectometer test results. The measured K values were consistent with those predicted using the proposed expression. In addition, the parameters in the expression were clearly defined, thereby providing basis for further study.

Vertical effects significantly affect the design and static analysis of large cable-stayed bridges. In the design of large cable-stayed bridges, the impact of cable sag must be considered. Generally, the Ernst equation is suitable when considering the cable sag effect for small spans (or the ratio of cable weight to tension). The Ernst formula assumes that a sag is a parabola curve and disregards the components of gravity. This assumption is inaccurate for some large-span bridges, and other accurate algorithms must thus be considered for analysis. In this work, the gravity and tensile force of cables are considered for long-span cable-stayed bridges. Furthermore, the effects of gravity on the directions of normal cables are considered. Analyses show that the gravitational components for cable directions should not be disregarded if the ratio of cable weight to tension force is large.

Iterative initial value of cable force based on influence matrix and linear programming is determined to study the cable force of long-span concrete-filled steel tube (CFST) arch bridge using the cable-hoisting construction method. Considering the effect of tangential displacement, we observed the appropriate cable force through the golden selection method and iterative forward erection. The cable force determination flow and method aimed at the installation shape are analyzed, which shows that the one-off tension of the cable force on a cable-hoisting CFST arch bridge focusing on installation shape is achieved and serves as a reference for similar engineering practices.

This work aims to study the mechanical mechanism of the post-peak tunnel surrounding rock state under grouted bolting support. The post-peak surrounding rock, which is under the effect of secondary stress from the free surface to the deep tunnel, can be divided into the residual strength, plastic softening, and elastic deformation zones according to the mechanical characteristic. The bolt axial stress and shear strength equations are obtained based on the principle of bolt bonding resistance to sliding deformation. The supporting force, which is provided by the grouted rock bolt through the rock-anchorage face, is assumed to be equivalent to the radial body force of the surrounding rock. Therefore, the balance equation is established by considering the influence of bolting support. The radii of the post-peak residual and softening zones, as well as the displacement and stress under grouted bolting support, is determined by combining the compatibility equations of the residual and softening plastic zones and considering rock post-peak strain softening and dilatancy with the balance equation. On the basis of theoretical research cases, the reinforcement effects between the grouting anchor and the surrounding rock, as well as bolting pretension, significantly improve the mechanical properties of the softening and dilatancy characteristics and control the development of the regional range and deformation of the surrounding rock.

To improve the accuracy of speed identification in car/automobile and two-wheeler collision accidents, the uncertainty theory was used to evaluate a collision speed model of the riders and the two-wheeler vehicles. First, a throwing distance-collision speed model of riders and two wheelers was built according to kinematic formulas, the theorem of kinetic energy, and the impulse theorem. Then, combined with the data on scene investigation of a collision accident of a car and an electric bicycle, the collision speed was calculated by the model. The optimum range of collision speed was obtained by using the uncertainty theory. Finally, the model and the evaluation method of uncertainty theory were proven to be reasonable and effective through MATLAB numerical verification, and PC-Crash simulation verification, as well as an analysis of the drive recorder.

This study aims to study the general behavior of drivers when searching for a parking lot. A sample investigation is conducted on the users of 18 selected parking lots in the Xicheng district of Beijing.The influencing factors of parking lot searching behaviors are analyzed by using investigation data. Results show that parking time, parking lot type, parking guide, and the situation of parking congestion significantly influence parking lot searching behaviors. The characteristic variables affecting parking lot searching time are determined, and a multinomial logitmodel of the searching time is established. The model is calibrated, and its effectiveness is verified. Results show that (1) the established model is feasible and has high prediction accuracy and practicability; (2) users quickly find a parking lot space when only few parking lot spaces are left; (3) users spend more time finding a satisfactory parking lot when several parking lots are left, and parking lot searching time is proportional to parking time.

In order to study the running state of the traffic flow that occurred at urban tunnel access, the urban tunnel traffic flow was taken as the object of the study. Then the dynamic accelerations of traffic flow in Xuanwu Lake tunnel、Drum-tower tunnel and Jiuhua Mountain tunnel were investigated by the texting vehicle method, and the acceleration noise values of different tunnels' traffic flow were calculated and analyzed based on computational model of acceleration noise. On the basis of data, the graphed relationship between the traffic flow state and acceleration noise by the simulation approach was obtained. According to the graphed different operating characteristics of vehicles, the level-of-service of unidirectional two-lane at urban tunnels was categorized into four classes; and the corresponding value range of average travel speed was determined. The results about the traffic congestion that gained by using evaluation indicators of acceleration noise would provide references of the engineering practices.

To determine the route choice behavior of a driver under a scenario with multiple-source travel information, the features of subjective travel time prediction were analyzed, and then a conceptual model of prediction was established. Various scenarios with multi-resource travel information, such as traffic radio and variable message signs (VMS), were designed based on a large driving simulation system. Then, the drivers were asked to search for travel information and perform driving tests at the minimum travel time to determine their route choice behavior characteristics. Results show that the scenario with traffic radio has the maximum average travel time and the lowest accuracy of prediction. However, traffic radio prevents drivers from encountering the route of serious delay; the scenario with VMS has the highest discrete degree, but accuracy in travel time prediction presents a limited service range. The scenario with traffic radio and VMS improves the accuracy of prediction with minimum variance and enables drivers to perform better than they do under a scenario with a single information source.

When no guidance information is available, drivers often depend on recent experience to select a travel route.This paper is based on the theory of behavior reinforcement, establishing a vehicle route choosing model with out guidance information. The model is based on a finite rational fuzzy game.The game equilibrium results are obtained under different initial conditions. Numerical simulation shows that with no guidance information, the traffic flow distribution of the network eventually reaches a balance given by theoretical analysis. Some network environments form a stable equilibrium game that does not release induction information. However, in other network environments, the traffic flow distribution forms a non-stable equilibrium game.Therefore, the traffic capacity of the entire network cannot be taken advantage of, and certain management measures must be considered.

The accuracy of safety speed is insufficient because the grandeur of a vehicle is oversimplified by the curve-safety-speed calculation method, which plays a core decision-making role in the current curve-speed warning control system. Based on the nonlinear characteristic of tire and dynamic stiffness of suspension, the vehicle dynamic model with TruckSim was built by using an 8-meter-long full-load bus as the research object. The orthogonal simulation experiment of driving speed to different radii was conducted, and the mathematical response surface model of safety speed to curve radius was established. Finally, the critical speeds of the mathematical model calculation and the simulation test were compared under the same bend radius. Results show that the mathematical response surface model is a reasonable and accurate calculation method for calculating the safety speed of a vehicle that is turning on a curve. This model benefits the enhancement of vehicle active safety control technology.

A torque allocation method of PID(Proportion-Integral-Derivative)control based on BP (Back-Propagation) neural network is adopted to investigate the stability of a four-wheel independent-driving electric vehicle under extreme driving conditions andto control both yaw rate and sideslip angle. The main characteristic parameters of the stability are analyzed first, and the control variables are determined. Finally, the torque allocation control strategy for an independent-driving electric vehicle is designed. The controller has two layers:upper and lower. In the upper layer, according to the demand of longitudinal force, the PID control method is designed for speed control, and the PID controller based on the BP algorithm is set up to control the yaw moment created by yaw rate and side-slip angle. In the lower layer, a fuzzy control method is adopted to control the slip rate. Finally, the designed control system is simulated. Results show that the designed torque allocation control strategy ensuresdriving safety and vehicle stability under extreme driving conditions.

The passenger value is used to segment the intercity passenger transport market. According to its advantages or disadvantages in each submarket, highway passenger transport (referred to as "highway mode" hereafter) is positioned to generate business strategies for operators. First, a model is built to analyze the value measuring elements with passenger expectation, actual perception quality, and service repair as cause variables, and their behavioral intention as the outcome variable. Then, the intercity passenger transport market is divided into four submarkets (economical, service-oriented, prudent, and efficiency-oriented) based on the measured values and sample passenger data from Dalian to Shenyang, and by using factor analysis and K-means cluster. Finally, the role of the highway mode is repositioned based on the service attributes that passengers in each submarket are concerned with. The development strategies of the highway mode in the new context are discussed in terms of maintaining and expanding advantages, increasing efficiency, and improving service quality.