Method for continuous on-site repaving of an asphalt mixture layer of paved road pavement and a motor-driven vehicle system therefor

Abstract

Problem to be Solved The present invention provides a method for continuous on-site repaving of an asphalt mixture layer of a road pavement and a motor-driven vehicle system therefor, while moving the motor-driven vehicle system. Solution to Solve the Problem A method for continuous on-site repaving of an asphalt mixture layer of a road pavement, which comprises a step of applying heat to a surface of an asphalt mixture layer so as to allow the heat to reach to a predetermined depth and soften the asphalt mixture layer, a step of scarifying the asphalt mixture layer to the predetermined depth to obtain an old asphalt mixture, a step of adding a coarse graded aggregate being stored to the old asphalt mixture, a step of obtaining a reinforcing asphalt mixture which the coarse graded aggregate being added therein, a step of spreading the reinforcing asphalt mixture onto a remaining layer of the asphalt mixture layer to form a reinforcing layer having an elastic modulus greater than that of the remaining layer, a step of adding an asphalt mixture for a new surface layer being stored onto the reinforcing layer, a step of spreading the asphalt mixture for a new surface layer to form a new surface layer, and a step of compacting the reinforcing layer and the new surface layer together while heat still being stored.

1 . A method for continuous on-site repaving of an asphalt mixture layer of a road pavement with a motor-driven vehicle system therefor, comprising the steps of;
 (a) applying heat to a surface of the asphalt mixture layer so as to allow the heat to reach to a depth exceeding a boundary surface between a base layer and a surface layer of the asphalt mixture layer or to a depth within the asphalt mixture layer equivalent to the depth exceeding the boundary surface and softening the asphalt mixture layer,   (b) scarifying the heated and softened asphalt mixture layer to the depth exceeding the boundary surface between the base layer and the surface layer of the asphalt mixture layer or to the depth within the asphalt mixture layer equivalent to that depth exceeding the boundary surface to obtain an old asphalt mixture,   (c) adding a first new material to the old asphalt mixture, the first new material being stored in a storage apparatus at a temperature preventing re-aggregation, the first new material being any of a coarse aggregate, a coarse aggregate covered with asphalt or an asphalt mixture having a particle size distribution including coarse aggregate mixed therein,   (d) mixing the first new material with the old asphalt mixture to form a reinforcing asphalt mixture,   (e) spreading the reinforcing asphalt mixture over the'remaining layer of the asphalt mixture layer left un-scarified in the step (b) to form a coarse graded reinforcing layer having an elastic modulus greater than that of the remaining layer,   (f) adding a second new material onto the formed coarse graded reinforcing layer, the second new material being stored in a storage apparatus at a temperature preventing re-aggregation, the second new material, being a fresh asphalt mixture for a new surface layer,   (g) spreading the second new material to form the new surface layer, wherein the step of spreading the second new material being linked with the step (e), and,   (h) compacting the coarse graded reinforcing layer formed over the remaining layer and the new surface layer together while heat still being stored.   
     
     
         2 . The method as defined in  claim 1 , further comprising a step of carrying in, prior to said step (b), the first new material and the second new material at different timings conveyed from outside the motor-driven vehicle system to respective one of the storing apparatus coincidentally with the different timings. 
     
     
         3 . The method as defined in  claim 1  or  2 , wherein the first new material is any one of an aggregate or aggregate covered with asphalt having a greater diameter than the greatest diameter of an aggregate included in the asphalt mixture layer or an asphalt mixture having a particle size distribution including coarse aggregate mixed therein having a greater diameter than the greatest diameter of an aggregate included in the asphalt mixture layer. 
     
     
         4 . The method as defined in  claim 1  or  2 , wherein the reinforcing asphalt mixture includes an aggregate having a greater diameter than the greatest diameter of an aggregate included in the asphalt mixture layer for 5 to 35 weight % to the total weight. 
     
     
         5 . The method as defined in  claim 1  or  2 , wherein said step (d) further comprises a step of adding an asphalt rejuvenating agent when mixing the old asphalt mixture with the first new material added therein. 
     
     
         6 . The method as defined in  claim 1  or  2 , wherein the second new material is an asphalt mixture including an aggregate having a substantially same particle size distribution as that of an aggregate included in the asphalt mixture layer. 
     
     
         7 . The method as defined in  claim 1  or  2 , wherein said step (e) further comprises a step of spreading an asphalt emulsion or a material for enhancing water proof property and bonding property over the remaining layer to bond the remaining layer and the coarse graded reinforcing layer. 
     
     
         8 . A motor-driven vehicle system for continuous on-site repaving of an asphalt mixture layer of road pavement comprising;
 a pre-heater vehicle for applying heat to a surface of the asphalt mixture layer of road pavement so as to allow the heat to reach to a depth exceeding a boundary surface between a base layer and a surface layer of the asphalt mixture layer or to a depth within the asphalt mixture layer equivalent to the depth exceeding the boundary surface and thereby to soften the asphalt mixture layer;   a miller vehicle including;
 a first tank for storing a first new material at a temperature preventing re-aggregation, the first new material being any of a coarse aggregate, a coarse aggregate covered with asphalt or an asphalt mixture having a particle distribution including a coarse aggregate, 
 a scarifying means for scarifying the heated and softened asphalt mixture layer to the depth exceeding the boundary surface or to the depth within the asphalt mixture layer equivalent to the depth exceeding the boundary surface to obtain an old asphalt mixture, and, 
 a first adding means for adding the first new material stored at a temperature preventing re-aggregation and discharged out of the first tank to the old asphalt mixture; 
   and,   a mixer vehicle including;
 a second tank for storing a second new material at a temperature preventing re-aggregation, the second new material being a fresh asphalt mixture for a new surface layer, 
 a mixing means for receiving the old asphalt mixture which the first new material is added therein and mixing the first new material with the old asphalt mixture to obtain a reinforcing asphalt mixture, 
 a first screed for spreading the reinforcing asphalt mixture over a remaining layer of the asphalt mixture layer left un-scarified by the scarifying means to form a coarse graded reinforcing layer having an elastic modulus greater than that of the remaining layer, 
 a second adding means for adding the second new material stored at a temperature preventing re-aggregation and discharged out of the second tank over the coarse graded reinforcing layer, and, 
 a second screed for spreading the added second new material to form a new surface layer, an operation of the second screed being linked with an operation of the first screed. 
   
     
     
         9 . The motor-driven vehicle system as defined in  claim 8 , further comprising a compacting means for compacting the coarse graded reinforcing layer formed over the remaining layer and the new surface layer formed over the coarse graded reinforcing layer together while heat still being stored. 
     
     
         10 . The motor-driven vehicle system as defined in  claim 8  or  9 , wherein the miller vehicle further comprises a relaying receiving-discharging apparatus for receiving and discharging the first and the second new material carried in at different timings from outside the motor-driven vehicle system, and a new material conveying apparatus including at least 2 continuous conveying paths and having a switching apparatus for carrying the first and the second new material discharged from the relaying receiving-discharging apparatus respectively into the first and the second tank coincidentally with the different timings, wherein, when the first new material is carried from the relaying receiving-discharging apparatus to the first tank, the switching apparatus disconnects the at least 2 continuous conveying paths of the new material conveying apparatus to form a carry-in opening and the first new material is carried into the first tank via the carry-in opening, wherein, when the second new material is carried from the relaying receiving-discharging apparatus into the second tank, the switching apparatus closes the carry-in opening formed in the new material conveying apparatus to form 1 conveying path by connecting the at least 2 conveying paths and the second new material is carried from the relaying receiving-discharging apparatus into the second tank via the 1 conveying path. 
     
     
         11 . The motor-driven vehicle system as defined in  claim 8  or  9 , wherein the first new material is any one of an aggregate or aggregate covered with asphalt having a greater diameter than the greatest diameter of an aggregate included in the asphalt mixture layer or an asphalt mixture having a particle size distribution including coarse aggregate mixed therein having a greater diameter than the greatest diameter of an aggregate included in the asphalt mixture layer. 
     
     
         12 . The motor-driven vehicle system as defined in  claim 8  or  9 , wherein the reinforcing asphalt mixture includes an aggregate having a greater diameter than the greatest diameter of an aggregate included in the asphalt mixture layer for 5 to 35 weight % to the total weight. 
     
     
         13 . The motor-driven vehicle system as defined in  claim 8  or  9 , wherein the second new material is an asphalt mixture including an aggregate having a substantially same particle size distribution as that of an aggregate included in the asphalt mixture layer. 
     
     
         14 . The motor-driven vehicle system as defined in  claim 8  or  9 , wherein the mixer vehicle further comprises a rejuvenating agent adding means for adding an asphalt rejuvenating agent when mixing the old asphalt mixture with the first new material added therein. 
     
     
         15 . The motor-driven vehicle system as defined in  claim 8  or  9 , wherein the mixer vehicle further comprises a third tank for storing an asphalt emulsion for bonding the remaining layer and the coarse graded reinforcing layer or a material for enhancing water proof property and bonding property. 
     
     
         16 . The motor-driven vehicle system as defined in  claim 8  or  9 , wherein the mixer vehicle further comprises a storing space arranged between the mixing means and the first screed, for adjusting a supply volume of the reinforcing asphalt mixture onto the remaining layer. 
     
     
         17 . The motor-driven vehicle system as defined in  claim 8  or  9 , wherein the mixer vehicle further comprises a storing space arranged between the first screed and the second screed, for adjusting a supply volume of the second material onto the coarse graded reinforcing layer.