Chinese Research Institute of Highway
Chinese Research Institute of Highway
Chinese Research Institute of Highway | Date: 2016-11-30
A patch and a method for repairing an asphalt pavement are provided. The patch includes a first asphalt layer having first and second bonding surfaces opposite to each other, a second asphalt layer having third and fourth bonding surfaces opposite to each other, the third bonding surface of the second asphalt layer facing the second bonding surface of the first asphalt layer, a textile layer disposed between the second bonding surface of the first asphalt layer and the third bonding surface of the second asphalt layer, and a crushed stone layer disposed on the first bonding surface of the first asphalt layer. A pothole of an asphalt pavement may be repaired quickly by using the patch according to the present disclosure. Moreover, the patch according to the present disclosure may not pollute environment around roads.
Zhang X.,Chinese Research Institute of Highway
2016 2nd International Conference on Frontiers of Signal Processing, ICFSP 2016 | Year: 2016
In order to overcome the defects of shuffled frog leaping algorithm (SFLA) such as slow searching speed in the late evolution and easily trapping into local extremum, an Opposition-based Chaos Shuffled Frog Leaping Algorithm (OCSFLA) was originally proposed in this paper. It utilized the opposition strategy to generate initial population, adopted a modified frog leaping updating formula, and combined the frog population movement with the chaotic motion, thus putting forward a chaos shuffled frog leaping optimization model. Tests on five standard test functions show that OCSFLA has an obvious improvement in whatever the convergence precision, the convergence speed, the optimization time as well as the stability. © 2016 IEEE.
Chuna W.,Chinese Research Institute of Highway
Proceedings - 9th International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2017 | Year: 2017
It is widely known all drivers need to slow down driving speed and look around carefully when they approach intersections. In order to study the driving speed changing when drivers go straight through intersections, 1200 segments of trips from natural driving database are selected. Based on the selected data, the pattern of driving speed changing, the driving speed when approaching and passing intersections, and the time of driving speed starting to change are analyzed. The result shows that the majority of drivers slow down their driving speed during approaching an intersection, choose driving speed between 40-60 km/h to pass an intersection, and reduce the driving speed through the intersection from 6 seconds to 9 seconds before the intersection. © 2017 IEEE.
Xu C.,Chinese Research Institute of Highway
Modern Tunnelling Technology | Year: 2016
Based on laboratory tests, the variation laws of several mechanical factors of rock specimens (sandstone) from the Shihuoshan tunnel of Xinjiang were studied, including the wave velocity, mass, triaxial compressive strength, uniaxial compressive strength and elasticity modulus with burning temperatures of 400℃, 600℃, 800℃ and 1 000℃. The results show that: 1) the wave velocity changes little for temperatures less than 400℃, while it de⁃ creases under temperatures more than 400℃, especially between 400℃ and 600℃; 2) the relationship between the triaxial compressive strength and burning temperature/confining pressure is complex and the variation laws of the triaxial compressive strength and its relevant parameters are different under the critical temperatures just below or above 800℃; 3) the uniaxial compressive strength increases with an increase of temperature when the temperature is below 600℃, while it decreases when the temperature exceeds 600℃. © 2016, Editorial Office of "Modern Tunnelling Technology". All right reserved.
Chinese Research Institute of Highway, Beijing Municipal Road & Bridge Building Material Group Co. and Guangxi Communications Investment Group Co. | Date: 2012-10-16
The invention relates to mix composition determination method of coarse graded high modulus asphalt concrete with skeleton embedded structure, which belongs to the road engineering design field. The invention use low labeled hard asphalt AH-30# with penetration degree no greater than 30 (0.1 mm); the nominal maximum aggregate size no smaller than 26.5 mm; building mineral aggregate gradation of the mix by the idea of course aggregate gap gradation; using gradation design method of asphalt mixture based on closest compact condition to select the optimal oil-stone ratio. The concrete invented is technology reliable and economy reasonable which has good anti-deformation capacity and carrying capacity, and the high temperature stability is obviously improved, at the same time the mechanics performance of the asphalt mixture is improved, the strength of this new asphalt mixture is more than 50% higher than that of common asphalt mixture, its dynamic complex modulus is 30% higher than that of similar foreign products, which has very excellent road performance.
Chinese Research Institute of Highway and Guangxi Communications Investment Group Co. | Date: 2012-10-15
The invention involves a method to structure mineral aggregate gradation by using three control points & two curves, including the following steps: (1) Three control points are determined according to the property of the mixtures: nominal maximum size of aggregate and its passing rate, nominal minimum size of aggregate and its passing rate, and the discontinuity point between the coarse aggregate and the fine aggregate and its passing rate. (2) The grading curves of the coarse and the fine aggregate are selected respectively with Power function model, Exponential function model and Logarithmic function model. (3) Measure the stamped density and the stamped voids in mineral aggregate, and then choose the grading of the coarse and the fine aggregate on the basis of the project need. The invention can help constitute different gradation curves in line with local materials from different areas and sources. In this way can the mineral aggregates property give the full play to the mixtures, and its a good guide to the mix proportion of the asphalt mixture.
Wang Y.-F.,Beijing Jiaotong University |
Wu H.-L.,Chinese Research Institute of Highway
Journal of Composites for Construction | Year: 2011
Most previous studies on concrete short columns confined with fiber-reinforced polymer (FRP) composites were based on small-scale testing, and size effect of the columns still has not been studied thoroughly. In this study, 99 confined concrete short columns wrapped with aramid FRP (AFRP) jackets and 36 unconfined concrete short columns with circular and square cross sections were tested under axial compressive loading. The circular specimens were divided into six groups, and the square specimens were divided into five groups, with each group containing different levels of the AFRP's confinement. In each group, the specimens were geometrically similar to one another and had three different scaling dimensions. Statistical analyses were used to evaluate the size and interaction effects between the specimen size and the AFRP's confinement, and a size-dependent model for predicting the strength of the columns was developed by modifying Baznt's size-effect law. The experimental results showed that the size of a specimen had a significant effect on the strength of AFRP-confined concrete short columns, lesser effect on the axial stress-strain curves, and slight effect on the failure modes. The modified Baznt model was in good agreement with the experimental data. © 2011 American Society of Civil Engineers.
Guo Y.L.,Chinese Research Institute of Highway
Applied Mechanics and Materials | Year: 2014
Cable corrosion is a serious problem in cable-stayed bridge. The paper analyzes the reason of cable corrosion and introduces the method of damage monitoring and detection. © (2014) Trans Tech Publications, Switzerland.
Liu G.G.,Chinese Research Institute of Highway
Applied Mechanics and Materials | Year: 2014
In the ear of information society, network security have become a very important issues. Intrusion is a behavior that tries to destroy confidentiality, data integrality, and data availability of network information. Intrusion detection systems are constructed as a software that automates the automatically detects possible intrusions. In this paper, we present the existing intrusion detection techniques in details including intrusion detection types, firewalls, etc. © (2014) Trans Tech Publications, Switzerland.
Wang C.-B.,Chinese Research Institute of Highway
Yantu Lixue/Rock and Soil Mechanics | Year: 2012
The failure process of tunnel constructed in homogeneous rock is studied by using model test and discrete element method (DEM); and the laws of the stress of surrounding rock and their displacement during the failure process are analyzed. The results of model test match the results of numerical simulation perfectly. From the results some conclusions can be drawn. The surrounding rock of the arch crown deforms obviously after excavation. The failure of the surrounding rock initiates from the arch crown and develops upward progressively until a stable caving arch is formed. The radial stress and tangential stress in a given range of the surrounding rock decrease after excavation. The range in which tangential stress of the surrounding rock decreases expands outward during the tunnel failure process. The vertical stress of the arch bottom increases after collapse. The displacement increment from excavation to collapse is the biggest and that during the collapse is the smallest.