Analysis Of Joint Mechanical Response Of Joints Of Cement Pavement Joints Under Biased State

Due to construction errors and external factors,the dowel bars tend to deviate from the original design's horizontal position,resulting in different ways and different degrees of deviation.Under the influence of vehicle load and temperature field,the movement of the biased dowel bar will be limited,resulting in stress concentration around the biased dowel bar and premature failure.This paper will consider the different ways of deviation and the degree of deviation of the dowel bar,and the type of load that the cement concrete pavement will mainly bear during service.Combined with the plastic damage model of concrete,this paper mainly discusses the mechanical behavior of concrete and the plastic damage of concrete under vehicle load and temperature load.The main research contents of this paper are as follows.(1)Establish a full-size single-layer finite element model with biased dowel bars,assuming that the dowel bar is displaced in the vertical direction or in the horizontal direction.Based on this finite element model,the stress and the plastic damage state of the concrete around the biased dowel bar was analyzed.The load of vehicle,the degrees of deviation and the modes of deviation were all be taken into account.It is found that the stress and plastic damage of the concrete is greater when the dowel bar is misaligned by 6° than when the dowel bar is misaligned by 12°.At the same time,when the dowel bar is horizontally misaligned,the concrete at the deflection end of the dowel bar is more affected by the misalignment of the dowel bar.(2)Using ABAQUS's own thermal conduction analysis method,generate a temperature field that is linearly distributed along the thickness direction of the slabs.Then the temperature additional stress caused by the thermal expansion and the plastic damage state of the concrete was discussed.The stress and plastic damage of the concrete will increase as the displacement of the dowel bar is increased.When the dowel bar is vertically misaligned,the Tie connection end,the concrete above the dowel bar is subjected to compressive plastic damage,and the concrete under the dowel bar is subjected to tensile plastic damage.When the dowel bar is horizontally misaligned,the Tie connection end,the concrete which is far away from the displaced dowel bar is subjected to compressive plastic damage,however,on the other end,the concrete is subjected to tensile plastic damage.(3)Establish a full-size model with two adjacent biased dowel bars.The effects of vehicle load and temperature load were also considered separately.Investigate the stress and plastic damage state of the concrete around the biased dowel bar,when the two dowel bars showed different diviation models at the same time.Under the load of the vehicle,the deviation of the adjacent dowel bar would cause more serious plastic damage to the concrete around the original misaligned bar,but the adjacent bar misalignment mode has little effect.Under the influence of temperature load,when the dowel bar is displaced by 12°.the influence of the deviation of the adjacent dowel bar is more obvious.When the adjacent bar and the original misaligned bar were displaced in the same way but the opposite direction,the surrounding concrete of the original misaligned is the most affected.