Micro-surfacing has been commonly used in engineering applications as a preventive maintenance technology. However, given its low temperature stability and insufficient adhesion between layers, micro-surfacing leads to the insufficient durability of pavements and shows poor resistance to flaking and rutting easy to scatter,etc. Although the aggregate meets the requirements, micro-surfacing has an unreasonable gradation. Moreover, despite satisfying the requirements, the emulsified asphalt lacks bond strength, high temperature stability, and rutting resistance. To address these limitations, this study proposes a design method using multilevel dense built-in gradation waterborne epoxy micro-surfacing and investigates the main factors that affect road performance to improve the road durability of micro-surfacing. The particle size characteristics of different proportions of waterborne epoxy and emulsified asphalt mixtures were analyzed via laser particle size analysis test to study the curing time of waterborne epoxy resin (WER). According to the design system of the multilevel dense built-in gradation (MDBG) and the Bailey method, three types of micro-surfacing gradation were designed. The relationships of gradation, oil-stone ratio, and WER content with the abrasion and water resistances of micro-surfacing were tested by conducting 1 h and 6 d wet wheel abrasion tests. Results show that the curing of WER involves two stages, and that the blend ratio affects the curing time. The coarse aggregate ratio R_CA of MDBG can be used to design different gradations, and R_CA should be set between 0.5 and 1.0. The application of WER can improve the mixture abrasion and rutting resistance of micro-surfacing, whereas an appropriate aggregate gradation, oil-stone ratio, and curing time are identified as prerequisites for WER with an optimum content of 5.0% to 7.0%.

Non-water reacted two-component polymer (NRTCP), a newly invented polymeric material, has been widely used in various engineering projects because of its advantages, such as impermeability, time saving, and labor saving. Impact resonance test (IRT) is a type of nondestructive test method. This method has been applied to obtain the dynamic elastic modulus of Portland cement concrete and pavement asphalt traditionally, but it has not been used to test NRTCP. In this study, the damping ratio and elastic modulus of NRTCP are obtained through IRT under different circumstances, such as various liquid depths, salt contents, immersion times and densities. Results show that all changes remarkably affect the damping ratio and dynamic elastic modulus of NRTCP. These findings provide a reference for NRTCP usage in oceanic traffic engineering.

To solve the fatigue cracking problem in orthotropic steel decks (OSD) and to prevent the early damage of bridge pavements resulting from the low stiffness of the bridge deck system, epoxy-resin-perfused concrete (RPC) pavements were developed for improving the modulus and road performance of paving materials. The mechanical and road performance of RPC and the bonding performance of the waterproofing adhesive layer were studied via laboratory experiments. The mechanical property of RPC pavements and their protective function on OSD were analyzed by using a finite element model. Composite beam fatigue life and acceleration loading tests were performed on a scaled model to verify the performance of these pavements. Results show that RPC has excellent high-and low-temperature stability and water stability that can meet the requirements and has a relatively long fatigue life. The bonding strength of RPC pavements and steel plate is better than that of epoxy asphalt concrete and Gussasphalt concrete pavements. RPC pavements have a relatively low tensile stress on the surface and a relatively high shear stress below the surface, but these stresses are far lower than the material strength. When paved with RPC, the stress in the fatigue details of OSD is reduced by more than 20%. The maximum relative deflection between ribs, the minimum curvature radius, and the relative deflection to span ratio of RPC are also favorable, thereby providing additional protection for the bridge deck system. The fatigue life tested with a five-point bending composite beam is more than 1 million times, which meets the requirements. In the acceleration loading test, RPC pavements do not show any rut, whereas the OSD shows no cracking when loaded for 12 thousands times. The engineering application results demonstrate the feasibility of using RPC pavements and show that these pavements and OSD endure no damage.

Creep is an inherent property of concrete materials, and an accurate prediction of creep-induced prestress is critical in designing a prestressed concrete structure. The comparison of codes or specifications of different countries on concrete structures was performed in this study. A basic model of prestress loss caused by creep was first deduced from a simple engineering model, and then the derived model was compared with the calculations obtained by different codes. Results show that the overall fundamentals and considerations of these codes are similar. Among these codes, the formulas specified by the Chinese Codes, European Code (DD ENV 1992-1-1), and AASHTO Code (AASHTO LRFDUS-5-M) were similar to the concrete aging formula, while the ACI Code (ACI 209R-92), Australian Code (ACI 209R-92), and Canadian Code (CSA-S6-06) depended more on empirical coefficients obtained via experiments. In the calculation example, the value of creep coefficient directly affected the calculating result of prestress loss. By comparing of the creep models adopted in Code for Design of Concrete Structures (GB50010-2010), European Code (DD ENV 1992-1-1), ACI Code (ACI 209R-92), and Railway Code (TB10002.3-2005). The effects of input parameters on calculation of creep coefficient were discussed in details. This study revealed the appropriate conditions using different codes.

Double-deck curved girder bridges can achieve large climb in a short distance, and their seismic response differs from that of regular bridges due to their special structural form. The constraint system of bridges, which consists of bearings and shear keys, has a key influence on the seismic response of the bridge structure. Accordingly, this research aims to develop a reasonable constraint system for double-deck curved girder bridges. A finite element simulation of a double-layer curved steel box girder bridge is also conducted to compare some indexes,which are the displacement of bearings with the curvature of the pier section. The shear bolt is selected as the limit device to study the influence of shear bolts and different bearings on the seismic response of the double-deck curved girder bridge structure. Under the influence of ground motion, the displacement of the upper bearings of double-layer curved girder bridges is generally larger than that of the lower bearings. The double-layer constraint system makes the section curvature and ductility in the middle of the pier smaller than that at the top and bottom of the pier. The spherical steel bearings have a small displacement, whereas the pier has a large internal force. After setting the shear bolts, the displacement of the spherical steel bearings decreases, whereas the damage to bridge piers does not show obvious changes. When the displacement of elastomeric pad bearings increases, sliding occurs under a low ground motion intensity, thereby reducing the degree of damage to the bridge pier. Moreover, the application of shear bolts limits the displacement of bearings and subsequently increases the seismic force being transmitted to the pier whose damage is the most serious. However, the displacement of pot bearings is relatively small, and the displacements of the upper and lower layers are close. In addition, the seismic inertial force of the superstructure is relatively uniform, thereby protecting the piers to a certain extent. After setting the shear bolts, the deformation falls within an allowable range, whereas the damage to the bridge piers slightly increases. Therefore, combining pot bearings with shear bolts creates a reasonable constraint system for double-deck curved girder bridges.

This paper utilizes numerical simulation software and the solid engineering of the Mali River II Bridge as a case study to understand the application effect of rigid long-short pile on the soft soil layer under the side roadbed, to analyze the influence of different factors on the treatment performance of rigid long-short pile, and to determine how the use of rigid long-short piles affect the lateral foundation in high subgrade fill. The treatment effect and stress distribution characteristics of the rigid long-short pile under different layout patterns and treatment distances are also analyzed, and related engineering proposals are proposed. Under lateral loading, the lateral compression deformation of the soft interlayer significantly affects the displacement of the pile, the resistance of the soil on the side of the pile, and the bending moment of the pile. A significant inflection point is observed in the displacement of the pile body at 16 m (interface between the soft soil layer and the strong weathered rock formation), and the resistance of the pile side soil and bending moment of the pile body reach their maximum at 16 m. The pile foundation shows a similar displacement in different positions yet shows various degrees of influence. The most disadvantageous position is located closest to the outside of the pile, and the bearing capacity of the side pile foundation can be improved by utilizing an appropriate design. Compared with square and staggered layouts, the rigid long-short piles in the quincunx layout play the most significant roles in reducing the effect of the lateral deformation of the weak intercalated layer on the bridge pile foundation. The treatment effect of the reinforcement zone in the quincunx layout differs under various treatment distances. The treatment distance of the reinforcement zone should neither be too close to nor too far from the pile foundation, and a treatment distance of 8 m is considered optimal.

The fork road of a large section tunnel plays a key role in tunnel construction because of its large cross section, complex force, and challenges to construction. A fork road divides a tunnel into several construction work sections, thereby shortening the construction period of a project and accelerating the tunnel construction progress. The fork road of a mountain tunnel enters the main hole by using the bench expansion method. The end of the incline uses upper and lower benches and is constructed 4.2 m upward from the upper bench to determine the height of the pilot tunnel. The main hole boundary line is excavated to complete the pilot tunnel construction. The main hole adopts the three-bench method with upper, middle, and lower benches of 5.3, 3.59, and 3.31 m, respectively, installed along the import and export directions. The main hole of the sectional area (92.1 m²) is a large cross section tunnel whose high span ratio leads to the poor stability of the surrounding rock and support. Therefore, the main hole should be strengthened in the construction to maintain the stability of the tunnel. By using the ABAQUS finite element software for the numerical analysis of the tunnel, the stress distribution of the surrounding rock after tunnel excavation can be intuitively simulated, which can provide a reasonable basis for tunnel construction. The anchor, steel mesh, lining, grille, and steel frame are constructed according to different surrounding rock grades. The monitoring measurement, which monitors the small changes in the surrounding rock and support, can control the stability of the surrounding rock during excavation and the dynamic information of the supporting structure. The regression analysis of monitoring data can reflect the change rule of the surrounding rock, analyze the displacement rate of each stage, and predict the final displacement value. The monitoring data show that the accumulative deformation range of subsidence and surrounding convergence range from 10 mm to 17 mm. Therefore,,the proposed technology can realize a safe, economic, and efficient construction of fork roads and provide a reference for similar conditions.

The primary lining structure plays a key role in blasting tunnel construction, and its intensity change and dynamic response directly affect the security of tunnel structures. To investigate the dynamic response of the primary lining structure under blasting loads, combing field test with numerical simulation was conducted in the new passenger line railway that traverses from Beijing to the Shenyang TJ-1 (Liaoning) Sanlengshan tunnel. The peak particle vibration velocity data were recorded by conducting eight monitoring tests at three measuring points by using TC-4850. The Sadaovsk formula for the propagation law of peak particle vibration velocity was fitted by using the least squares method. The numerical simulation software LS-DYNA was used to obtain material and equation parameter based on, and the reliability of the numerical model was verified by using the propagation law of peak particle vibration velocity to determine the variations in the stress and displacements in key locations (i.e., skew, haunch, spandrel, and vault) while considering the strength of the primary lining. Results show that the maximum stress of the tunnel primary lining structure at the skew and vault in the X direction is greater than at the haunch and spandrel. The maximum stress values in the Y and Z directions are 0.1 181 MPa and 0.239 1 MPa at the skew, respectively. The maximum stress value in the Z direction is larger than that in the X and Y directions. The maximum displacement value of the tunnel primary lining structure is 3.61 mm at the haunch and appears in the Z direction much earlier than in the X and Y directions. By increasing the primary lining strength of C25 and C35, the stress becomes positive, whereas the displacement shows a negative relationship.

Sedimentary rocks are commonly found on the Earth's surface. As the most common type of sedimentary rock, sandstone plays an indispensable role in engineering construction. To understand the changes in the surface roughness of building materials during fire, this research performs a simulation by using the high temperature quenching method. The surface roughness of rock samples was measured by using a surface roughness meter and was quantified by using the arithmetic mean error of the contours (Ra). The following results are obtained through data processing:(1) When the temperature was 500℃ or less, the surface roughness of the rock mass showed a relatively small amplitude and irregular fluctuations. (2) The surface roughness increased as the temperature rose from 500℃ to 600℃. (3) At temperatures above 600℃, a comprehensive analysis of Ra, Ry, and Rz, which quantify the sample fracture extension, revealed that the surface roughness continued to increase along with temperature. (4) The structure and composition of the minerals in the yellow sandstone samples changed along with an increasing temperature, and these changes could alter the amplitude of rock mass surface roughness, which is an internal factor that affects the overall surface roughness of the rock mass. Overall, the surface roughness increased along with temperature.

The traditional architecture of an urban intelligent transportation data network has a hierarchical distribution. In this architecture, organizations independently manage and upload data, thereby making data sharing difficult to achieve. To solve this problem, a big data platform of urban intelligent transportation was built in this paper by using blockchain technology. In this platform, block data are used as the core, thereby removing the centralized data management of each organization. This method also completely changes the modes of data acquisition, processing, analysis, and storage and fully realizes platform-based large data sharing, decentralization, and distributed computing of the multi-source system of urban intelligent transportation. The big data platform of urban intelligent transportation based on blockchain technology should also solve several key problems, including the unification of data from different sources, the unified supervision and operation of data, and the compatibility with other advanced technologies. To solve these problems, the key technologies for large data platforms were evaluated from a technical perspective. These technologies include the unified technology of each node, the supervision and operation of multi-technology sharing, and the technology compatibility with vehicle networking and vehicle-road collaboration. By taking the problem of traffic flow data loss in road networks under haze as a simulation case scenario, the application of block chain technology was described. By taking some road networks in Beijing as examples, the simulation results show that under the traditional intelligent transportation data network framework, given the limitations of equipment installation layouts and subordinate management organizations, the coverage of road networks for data acquisition is greatly affected by the objective environment, which may lead to data loss. The data acquisition system should also run independently, thereby preventing data sharing at the bottom of the network. The big data platform architecture of urban intelligent transportation based on blockchain technology addresses the limitations of various organizations, realizes data sharing in urban intelligent transportation, and solves the data loss problem under the traditional network architecture.

Striving to develop public transport is an effective way of alleviating traffic congestion in large and medium-sized cities,and arterial transit signal priority is an important measure for improving the reliability of bus operations. However, only few studies have evaluated the quality of arterial transit signal priority scenarios. To address this gap this article proposes a transit signal priority scheme evaluation model. First, an evaluation index for arterial transit signal priority is established. Second,a decisive model of interval D-S evidence theory for arterial transit signal priority is built. Finally, to address the uncertainty of the index attribute and the one-sidedness of a single decision maker, the advantages and disadvantages of the model is assessed on the basis of D-S evidence theory, and the optimal scheme is selected. This research provides a new theory and method for the transit signal priority scheme that can effectively avoid the one-sidedness of a single decision maker in evaluating transit signal priority and the uncertainty of index attributes, and provides technical support for extending the application of transit signal priority.

Light-duty vehicle driving cycle is the basis to ascertain vehicle energy consumption, emission testing method, and standard specification, which is an important benchmark for the optimization and calibration of vehicle performance indexes. Based on the project of "China Automotive Test Cycles" of China Automotive Technology Research Center, this study collected five light-vehicles running on the urban road of Hohhot. After cutting and filtering the short segments of the automobile working condition, the eigenvalue of the automobile can be obtained to establish the automobile movement and idling segments database. The typical segments were extracted and combined to explore the velocity-acceleration distribution of the light-vehicles. The traffic flow and weight factors of different speed ranges were divided based on GIS all-road low-frequency traffic data. After obtaining the weighted velocity-acceleration distribution, the light-daty vehicle operating condition of Hohhot city was constructed with the chi-square test.

This study aims to improve the diversity and stress resistance of slope plant communities, promote its positive succession and ecosystem restoration in combination with the experiences of plant protection application in the high and steep cutting rock slope of the first-phase urban expressway of Xiazhou Avenue in Yichang and provide a theoretical basis for plant protection in high and steep cutting rock slopes. Fifty sample quadrats were set at the study area of the artificial restoration slope, and a vegetation survey was conducted. Different sites were divided in accordance with principal component and cluster analyses. Analytic hierarchy process was applied to build a selected system, in which all types of plants were comprehensively evaluated at different site conditions. Niche breadth and interspecific association of dominant plants in the plant community were determined on the basis of correlation analysis methods, and proper plant selection and configuration were proposed. Results showed that herbs comprised Green bristlegrass, Bahia grass, Cynodon dactylon, Kentucky bluegrass and Red smartweed and shrubs included Lespedeza bicolor, Indigofera amblyantha, Amorpha fruticosa and Indigofera pseudotinctoria have comprehensive evaluation result for I value at four different site conditions. The dominant plants among herbs were Kentucky bluegrass, Bahia grass, Green bristlegrass, Barnyard grass and Cynodon dactylon, and those among shrubs were Lespedeza bicolor, Indigofera amblyantha, Amorpha fruticosa, Leucaena leucocephala and Indigofera pseudotinctoria. The best niche breadths of herbs were Kentucky bluegrass, Bahia grass and Green bristlegrass, and those of shrubs were Lespedeza bicolor, Indigofera amblyantha and Amorpha fruticosa. A highly significant correlation existed between Cynodon dactylon, Green bristlegrass and Lespedeza bicolor, Indigofera amblyantha in accordance with interspecific association analysis. At different site conditions, the selection of plant species with significant correlation and high comprehensive evaluation value can effectively improve the relative stability of plant communities and rapidly realise the purposes of soil conservation and slope greening.