Study On Intelligent Compaction Control Technology Of Railway Subgrade

In the current construction of railway subgrade in China,the roller compaction technology is mainly determined through the con,struction of the test section,and fixed-pattern construction process control.There are problems such as the work efficiency of the subgrade is low,the compaction is uniform and poor quality and waste of construction resources etc in the compaction process.Therefore,th,rough research on the intelligent compaction control technology of railway embankment,it not only helps to improve the quality of roadbed construction and the working efficiency of the roller,but also it is of great significance to promote the reform of the construction technology of the railway subgrade and upgrade the technical level of China's railway construction.In this paper,theoretical analysis,laboratory tests,finite element numerical analysis and LabVIEW are used to in-depth study of soil compaction effect,vibration,response and intelligent comp.action control technology process design of "vibratory roller-soil" system.The main research results are as follows:'(1)The optimal vibratory compaction parameters of subgrade fillings were obtained.The vibratory compaction test was performed on the vibratory compaction device.The optimal vibratory compaction operating parameters of the group A and group C improved materials were obtained.It was verified that the two kinds of packing could reach the best compaction effect under the optimal vibratory compaction parameter combination mode.(2)Mastered the vibration response characteristics of the "Vibratory Roller-Soil" system.In the early stage of compaction,the vibrating wheel generates superharmonic vibration,and the frequency response of the vibrating wheel appears as a fundamental wave containing superharmonic components;in the later stage of compaction,as the soil is continuously densified,the vibrating wheel generates sub-harmonic vibration,and a richer sub-harmonic and super-harmonic components appear in the frequency spectrum of the vibration response,and enter into a chaotic state under certain conditions..(3)It proposes the operating state of the vibrating wheel during the compaction process.With the increase of the density of soil,the operating state of the vibrating wheel has undergone a change process of continuous contact,partial uplift,double jum,p or rocking motion,and chaotic motion.When the vibrating wheel vibrates or oscillates,a 1/2-fold harmonic component is generated in the frequency spectrum of the vibration response;reducing the vibration amplitude can,effectively suppress the bounce or sway and avoid the occurrence of chaotic vibration.(4)Determine the judgment criteria of the optimal vibration cormpaction mode.1)Vibration amplitude judgment criteria:Acceleration amplitude of the vibration frequency of the vibration wheel 1/2 times the operating frequency,that is,Al/2;2)Vibration frequency judgment criteria:The optimal vibration frequency is slightly larger than that of the"Vibratory roller-soil" system Natural frequency(larger 1-2Hz);3)Judgment criteria for running speed:The ratio of running speed to vibration frequency satisfies a constant constant,ie,v/f=0.03.(5)An intelligent compaction control flow for railway subgrade was formed.First,the subgrade intelligent compaction control flow design that according to the three stages of pre-construction preparation,construction process control and quality inspection;secondly,LabVIEW program development software was used to carry out the human-computer interaction interface design of the intelligent compaction control system;Finally,the operation process of the intelligent compaction control system was simulated by a virtual program,and the feasibility of the design flow of the intelligent compaction control system were verified.