Study On The Wearing Resistance And Anti-skid Performance Of The Pebble Man-made Sand Cement Concrete Pavement

The wear resistance and anti-skid performance of cement concrete pavement are two important indicators that determine the safe driving of the pavement.For the cement concrete pavement that has been built,river sand with higher hardness is mostly used.With the excessive exploitation of river sand,the resources have gradually depleted,and the lack of fine aggregate restricts the development of cement concrete pavement.As a renewable resource,machinemade sand has received strong support from national policies in recent years.Machine-made sand has gradually begun to replace river sand in cement concrete pavement projects.Because pebble has similar material source characteristics as river sand,machine-made pebble sand has become an important choice for fine aggregates for pavement.However,the research on the performance of pebble machine-made sand cement concrete pavement is still insufficient.Therefore,it is of great significance to carry out research on the abrasion and skid resistance of pebble machine-made sand cement concrete pavement to promote machine-made sand concrete pavement.This research is based on the theory of tribology,taking lithology,water-cement ratio and stone powder content as the main influencing factors of wear resistance and anti-skid performance.Through experimental methods,the wear resistance and anti-skid performance of pebble machine-made sand concrete pavement are studied,and the corresponding theoretical model is used in actual engineering.The main conclusions of this study are as follows:Fristly,through the experimental research on the basic physical properties of pebblemechanized sand,it was found that the quartz mineral-based pebble-mechanized sand has similar material characteristics with river sand,and its physical properties can meet the requirements of engineering specifications.And through the universal volume model of concrete,based on the full calculation theory and the existing theoretical and empirical formula,the ratio design method applicable to the pebble mechanism sand concrete pavement is established.Among them,by reasonably reducing the amount of cement per unit volume and adding water reducer,the phenomenon of accelerated hardening of concrete due to the presence of stone powder is slowed down,and the working performance of pebble-sand concrete is improved.Secondly,the wear mechanism of concrete pavement was summarized based on the existing wear theory,and the main influencing factors on the wear resistance of pebblemechanical sand concrete were analyzed,and experimental studies were conducted on the lithology,water-cement ratio and stone powder content.It was found that the abrasion resistance of pebble sand is better than that of limestone sand,and the reduction of water-cement ratio can significantly improve the abrasion resistance of pebble sand concrete,and the presence of appropriate amount of stone powder can improve the abrasion resistance of pebble concrete pavement.In addition,based on tribological theory,a three-component model of slip resistance of pebble-mechanized sand concrete was established,and the effects of lithology,water-cement ratio and stone powder content on slip resistance performance indexes were analyzed by pendulum meter tests.The test results showed that under different grinding times,the BPN values of pebble-mechanical sand concrete and limestone machine-sand concrete decreased by5.7% and 11.3% on average compared with those of river sand concrete,and the slip resistance of pebble-mechanical sand concrete was better than that of limestone,but weaker than that of river sand;compared with the specimens with water-cement ratio of 0.41,the BPN values of specimens with water-cement ratio of 0.35 and 0.38 decreased by Compared with the specimens with water-cement ratio of 0.41,the BPN values of the specimens with water-cement ratio of0.35 and 0.38 decreased by 19.28% and 14.85% on average,and the reduction of water-cement ratio could improve the slip resistance of pebble-mechanical sand concrete.And based on the test and the three-component model of slip resistance,the corresponding anti-slip construction measures of pebble-sand concrete are proposed.By paving the test section,the construction ratio applicable to the site was designed to verify the applicability of the pebble mechanism sand cement concrete pavement.And based on the study of wear and skid resistance,better construction measures were designed to meet the requirements of wear and skid resistance of the pavement in the actual project.