摘要:
为了研究新型复合路面CPC-AC(斜向预应力水泥混凝土+沥青混凝土复合路面)的层间结合行为,并探究其层间结合状态的表征及求解,提出以中性轴间距变化来表征层间结合状态,并推导了部分结合CPC与AC双层梁的层间结合系数叩的计算公式;设计了室内单层梁(沥青混合料和水泥混凝土)的小梁三点弯曲试验以及双层梁低温弯曲模拟试验,确定了单层小梁的弹性模量和部分结合双层梁抗弯刚度等计算参数;为分析层间结合系数η表征CPC-AC复合路面层间结合的能力,在CPC板表面设置了植石、刻槽以及凿毛3种处理方式,其层间黏结分别采用不同洒布量的SBS改性沥青及SBS改性沥青同步碎石封层,通过剪切试验论证了层间结合系数η表征CPC-AC复合路面层间黏结行为的可行性.研究结果表明:通过室内双层梁弯曲模拟试验和双层梁的抗弯刚度计算公式成功求得层间结合系数η;不同层间处理方式下,层间结合系数的变化规律与芯样剪切试验结果一致,说明层间结合系数叩可表征CPC-AC复合路面的层间结合状态;采用不同处理方法,使用不同层间黏结时层间结合系数差异较大,当CPC板采用植石+SBS改性沥青黏层方案,且沥青洒布量为0.4 kg/m2时,其结合状态最好,层间结合系数达到0.463.%To study interlayer bonding behavior and explore the representation and solution of the interlayer bonding state of CPC-AC (cross-tensioned prestressed concrete and asphalt concrete composite pavement),the spacing changes of neutral axis were proposed to characterize interlayer bonding state,and the calculation formulas of interlayer bonding coefficient η of partially bonded CPC-AC was derived.The three-point bending tests and simulation tests of double-layer beam at low temperature of indoor single beam were designed,and calculation parameters such as elasticity modulus of signal beam and flexural rigidity of partially bonded double-layer beam were determined.In order to analyze the interlayer bonding coefficient η,representing interlayer bonding ability of composite pavement,three treatments such as grooving,chiseling and crash stone were set on the CPC deck.Interlayer bonding adopted SBS modified asphalt and SBS modified asphalt synchronous chip sealing layer with different spraying volume,respectively.The feasibility of the interlayer bonding coefficient η representing interlayer bonding behavior of composite pavement was proved by shear test.The results show that ηcan be obtained by the indoor bending simulation test of double-layer beam and calculating formula of the flexural rigidity of double-layer beams.With different interlayer treatments,the change rules of η are in agreement with the result of shear tests,and therefore the ηhas the capability to characterize interlayer bonding state of CPC-AC composite pavement.The interlayer bonding coefficient is largely different with different treatment and interlayer bonding.The best bonding state for CPC is using crash stone and SBS modified asphalt tack coat,the spraying volume amount of asphalt is 0.4 kg/m2,and the interlayer bonding coefficient is 0.463.4 tabs,5 figs,28 refs.