CRTSⅠ型CA砂浆动态受压损伤试验

Dynamic Compression Damage Experiment of CRTSⅠType CA Mortar

在电子万能试验机上对现场取样的水泥乳化沥青砂浆（CA砂浆）试件在应变率1×10-5～1×10-2S-1下进行动态单轴抗压试验,分析了动态荷载下CA砂浆的抗压强度、弹性模量及临界应变随应变率的变化规律.结果表明：CA砂浆的抗压强度随应变率的增加而增大,CA砂浆的抗压强度、弹性模量及临界应变与应变率之间呈幂函数关系,并给出了抗压强度、弹性模量及临界应变受应变率影响的经验公式.以切线模量的退化来度量CA砂浆的损伤程度,分析了CA砂浆动态损伤槛值随应变率的变化规律：当加载到相同的应变时,应变率越低,CA砂浆的损伤程度越严重;随着应变率的增大,CA砂浆损伤应力槛值及损伤应变槛值均增大;当应变率较高时,应变率对损伤应力槛值与平均抗压强度的比值和损伤应变槛值与平均临界应变的比值影响不大.

Dynamic compression test of cement asphalt mortar（CA mortar） with field sampling specimens was carried out using an electronic universal testing machine with strain rates ranging from 1× 10-5s-1 to 1×10-2s-1.Influences of strain rate on compressive strength,elastic modulus and critical strain of CA mortar were analyzed.Results show that compressive strength of CA mortar increases with increasing strain rate.There are power relationships between compressive strength,elastic modulus and critical strain of CA mortar and strain rate,and the experiential formulas are established.Defining the damage degree of CA mortar by the reduction of the tangent modulus,influence of strain rate on damage threshold of CA mortar was analyzed.It is found that the damage degree of CA mortar under low strain rate is more serious than that under high strain rate when loading to the same strain.The damage stress threshold and damage strain threshold increase with increasing strain rate.When strain rate is high,the ratio of damage stress threshold to average stress and the ratio of damage strain threshold to average strain are insensitive to strain rate.