Study On Vibration Corrosion Behavior And Damage Evolution Of Cement Stabilized Macadam

The water damage of pavement base material has always been a difficult problem in road engineering,and dissolution and scouring are the main forms of water damage of cement-stabilized aggregates.The research on erosion damage,erosion fatigue,erosion test and anti-erosion performance of pavement base material has produced abundant results,which can guide the engineering practice to solve the erosion disease of pavement,but little on the dissolution of pavement base material.Based on the actual dissolution environment of highway,this paper studies the dissolution behavior and the evolution law of dissolution damage of cement-stabilized macadam materials,and improves the research on water damage of pavement base materials.（1）The key parameters affecting the dissolution of cement-stabilized macadam were obtained by investigating the working environment of highway.According to the key parameters,a new method of accelerating the dissolution was proposed,and a vibration accelerated dissolution device was developed.The experimental results show that the maximum scour pressure of the device is less than 1/12 of the scour test pressure,the specimen surface has no pitting surface after the test,the color range of phenolphthalein decreases rapidly with the increase of vibration time,and the vibratory accelerated solution method is safe and efficient.（2）Through the test,the influence of vibration frequency,vibration acceleration and dissolution temperature on the dissolution of cement-stabilized crushed stone was obtained.The vibration NH₄Cl solution test accelerated the dissolution and diffusion process at the same time,and the dissolution rate was greatly improved.The results of vibration dissolution test show that within the vibration frequency range of 80～180 Hz,the dissolution efficiency increases first and then decreases.The lifting acceleration or temperature can greatly improve the dissolution efficiency.About 150g Ca O can be dissolved in the vibrated NH₄Cl solution within 10h.Analysis of the mechanism of dissolution acceleration shows that temperature rising can increase the diffusion coefficient of ions,NH₄Cl can increase the diffusion flux of Ca²⁺,and vibration can promote the convection transfer of materials in the pores.（3）The dissolution damage evolution of cement-stabilized crushed stone was studied and the mechanism of the dissolution damage was revealed by comparing the vibration non-dissolution test with the vibration dissolution test,taking the properties,properties and acoustic emission parameters as the indexes.With the increase of dissolution time,the evolution results of character damage are dissolution depth increase and ultrasonic wave velocity decrease,the evolution results of performance damage are unconfined compressive strength and splitting strength decrease,and the evolution results of acoustic emission damage are impact count,amplitude and frequency and amplitude of energy parameters decrease.The dissolution data show that the damage caused by dissolution is far greater than the damage caused by vibration scour and the dissolution damage is an important reason for the water damage of cement-stabilized macadam materials.