Study On The Key Performance Evaluation And Interface Performance Of Polymer Concrete Bridge Deck Pavement Materials

Asphalt mixture is difficult to meet the requirements of waterproof performance and road performance of the bridge deck pavement,and it is easy to cause pavement and bridge structural diseases.Although the new polymer concrete bridge deck pavement material with excellent performance proposed recently can replace the traditional asphalt concrete bridge deck pavement material,its water stability is relatively poor.In view of this,this study proposes a method to reduce the void ratio by using the vacuum injection molding process（VIMP）,aiming to improve the water stability of the polymer concrete bridge deck pavement material,and further improve its road performance and waterproof performance.The new polymer concrete pavement material developed can also be used for the rapid repair of airport pavement.The main research contents and achievements include the following:First,in order to realize the full waterproof function and high performance,polyurethane（PU）and epoxy resin（EA）are used as the binders of bridge deck pavement materials in this study.The method of preparing polymer concrete bridge deck pavement materials by VIMP is proposed,the preparation process and parameters are determined,the basic road performance is studied and compared with the traditional compacted polymer mixture.The results show that compared with the traditional compacted polymer mixture,the void ratio of the polymer mixture prepared by VIMP is almost zero,and its stability and water stability are significantly better than the former,especially after immersion and freeze-thaw,the latter’s stability loss and splitting strength loss are almost zero,showing excellent water stability.Therefore,VIMP can effectively improve the stability and water stability of polymer mixture.Second,based on the theory of surface free energy,a new method of specimen preparation of contact angle test and AFM peak force mode scanning is proposed,the surface energy indexes of basalt aggregate and polymer binder were measured and calculated,and the bond performance between basalt aggregate and polymer binder was characterized from the angle of energy.The results show that the cohension work of EA is greater than that of PU,the adhesion work of EA-basalt is greater than that of PUbasalt,the interface performance of EA-basalt is better,the peeling work of EA-basalt is slightly less than that of PU-basalt,and the compatibility ratio is greater than that of PU-basalt,which indicates that the water loss resistance of EA should be slightly better than that of PU.The results of surface energy test are in good agreement with the macroscopic properties of the mixture.Third,based on the theory of interface transition zone,it is proposed that there may be a poor interface transition zone between polymer binder and aggregate.The micromorphology and modulus of the interface zone between aggregate and polymer binder are measured by AFM peak force mode scanning technology,and the interface performance between aggregate and polymer binder is characterized by micromechanics.The results show that the modulus at the interface between binder and aggregate is smaller than that at the interface far away from the interface,but the size of modulus and the width of the interface transition zone are closely related to the type of binder and aggregate.There is indeed a poor interface transition zone between polymer binder and aggregate,with the width varying from 50μm to 100μm.Finally,based on molecular dynamics simulation,a computer simulation method for the interface between PU and basalt aggregate is proposed.The interaction and energy change between PU and basalt aggregate are studied.The results show that the interface energy between four oxides and PU is Si O2 > Cao ≈ Al2O3 > Mg O,and the adhesion work of PU-oxides is Si O₂ > Cao ≈ Al₂O₃ > Mg O The adhesion work of water-oxides is Mg O > Ca O > Al₂O₃ > Si O₂,and the peeling work of PU-oxides is Si O₂ < Al₂O₃ < Ca O < Mg O.It shows the binding property of the acid-base aggregate to PU and aggregate is contrary to that to asphalt and aggregate.PU have better binding property and water loss resistance with acid aggregate...