Research On Structure And Control Principle Of 36-ton Intelligent Directional Vibratory Roller

In 2011,China promulgated the first national industry standard for continuous compaction control,"Technical Regulation for Continuous Compaction Control of Railway Subgrade Filling"(TB10108-2011).On April 12,2017,the first recommended standard for roadbed intelligent compaction “Highway Roadbed Filling Continuous Compaction Control System Technical Conditions” was issued.At this point,continuous compaction control of China’s high-speed railway and roadbed have the standard to obey.Intelligent compaction in Europe and the United States has been more than 10 years of research and application,however in the initial stage in our country.Internationally,there is no standard intelligent compaction measurement.Manufacturers can define their own intelligent compaction measurements,and to determine the compaction effect of the device.In the process of intelligent compaction,the first basic question is how to evaluate the compaction process is optimal,that is,in the shortest compaction time to achieve the required compactness;the second basic problem is how to determine the material have been fully compacted.In view of the above two basic problems,this paper mainly carries on the following work:(1)This paper,in order to realize the directional vibration of the vibratory roller,first designs the exciter structure of the roller.The exciter uses dual-axis excitation that two groups of four eccentric block drive through gear group,to achieve synchronous reverse rotation,and only get exciting force perpendicular to the plane of two vibrating shafts.(2)Based on the study of the structure and working characteristics of intelligent directional vibratory roller,the simplification and hypothesis is carried out to the conduct "machine-soil" dynamic model.The dynamic equations,providing a basis for the optimization of the working parameters,are listed and solved.(3)In this paper,the 36-ton vibratory roller is simplified as single-degree-of-freedom model so as to calculate the stiffness and damping of the shock absorber.The soil is simplified to the Kelvin model,and the "equation equivalence method" is used to determine the soil stiffness and damping.The two simplifications provide the parameter basis for the article.(4)In this paper,turns optimization and matching of the excitation frequency and amplitude of the vibratory roller,into the optimization and matching of excitation frequency and excitation angle.Considering the optimization goal R_T=Fs/Fe→1,establish the objective function,in constrain of "jumping" phenomenon and effect of vibration absorption.The optimization uses MATLAB software.The optimization results show that,with the compactness increasing the excitation angle of the intelligent directional vibratory roller should be changed within 0~90.The optimum excitation frequency of the intelligent directional vibratory roller should be in the range of 1.140 ~ 1.269 times of the second order resonance frequency of the vibration system.(5)Based on the optimized results data of the soil parameters,the fitting curve of the parameters of the intelligent directional vibratory roller and the soil parameters is obtained,and the optimum excitation angle is matched with the optimum excitation frequency.The matching results show that the amplitude change of the intelligent directional vibratory roller has a greater effect on the compaction effect than the frequency change under the optimum working conditions.In the early stage of compaction,the intelligent directional vibratory roller should work in condition of low frequency and excitation angle,so that the degree of compaction can be improved rapidly.In the later stage of compaction,in order to continue improve the compaction degree and to ensure the quality of compaction,the intelligent directional vibration roller should work in high frequency and excitation angle.(6)Install the acceleration sensor on the vibrating drum.When the acceleration of the vibrating drum is no longer changed,it means that the soil has been fully compacted and the compaction should stop.In order to realize the control of the optimal excitation frequency and the optimum excitation angle,the frequency hydraulic control loop and the amplitude hydraulic control circuit are designed to achieve the intelligent compaction.