The Application Of Multi Head Broken Petrochemical Technology In The Rehabilitation Of Old Cement Concrete Pavement

Nowadays,the mileage of cement concrete highway is rising in a rapid speed,which leads to repair the old cement concrete pavement.For many disadvantages of traditional methods overhauling the old cement concrete pavement,such as the environmental pollution of the abandoned concrete slab,the relevant technical staff at home and broad develop the old cement concrete pavement Multi Head Borken rubblization technology through their efforts.MHB rubblization technology is a kind of treatment technology for broken old cement concrete pavement,which is an important way of repairing or rebuilding the old cement concrete pavement.It is widely used at home and broad for its good effect of anti reflection crack,short construction period and small effect on the surrounding environment and the traffic.However,the research and application of the MHB rubblization technology is still at the beginning.So this paper make a research on the MHB rubblization technology through finite element simulation combined with the engineering practice.This paper builds an ABAQUS finite element model of pavement structure with circular pipe culvert based on longnan section of national highway G105.By selecting four typical load positions in the model that are the middle of the slab,the corner of the slab,the middle of the transverse joint and the middle of the longitudinal joint,this paper makes an analysis on the mechanical characteristics of the pavement under the different hammer positions,different subgrade modulus and different hammer energy and gives the definition of pavement damage coefficient using Zienkiewicz-Pande(Z-P)criterion.It is found that the hammer position,subgrade modulus and hammer energy jointly determines the mechanical properties and the crushing effect of old cement concrete pavement structure under load and crushing effect of petrochemical equipment.This paper makes a research and analysis of the safety of circular pipe culvert structure,uses the concept of subgrade work area to analyze MHB rubblization construction load affected zone,and calculate the stress and strain of circular pipe culvert structure through the finite element software.After a study,it is found that when the filling height more than 3.4 meters above the pipe culvert,multiple head crushing equipment affecting on the cement concrete pavement,the culvert structure will not be affected by pipe.And then through particle size test,compressive strength test and shear strength test,this paper make an analysis on the physical and mechanical properties of the pavement structure atLongnan section of national highway G105 after MHB rubblization.After the test,it is found that the old roads after MHB rubblization meet the requirements and regulations of rebuilding the road based course and the other layer can be overlay on the basis of the old roads.It is also reflected that the crushing effect of this section of the road is good.Finally,this paper uses results of the finite element analysis and the test data to determine construction parameters of the drop distance and height during the MHB rubblization construction and provide technical guidance for MHB rubblization construction by optimizing MHB rubblization construction technology.