In order to determine whether polyphosphoric acid (PPA) can partially or completely substitute styrene-butadiene- styrene (SBS) modifier while it does not adversely affect the resistance to thermal cracking of the...In order to determine whether polyphosphoric acid (PPA) can partially or completely substitute styrene-butadiene- styrene (SBS) modifier while it does not adversely affect the resistance to thermal cracking of the asphalt mixture, the low- temperature fracture properties of the PPA modified mixtures are evaluated and compared to the SBS modified mixtures. First, laboratory compacted test samples were tested by the indirect tensile test (IDT) and the newly developed fracture testing protocol, named as disk-shaped compact tension (DCT). Then, the effects of the test temperature and air-void ratio on the low-temperature fracture properties of asphalt mixtures were analyzed. The results show that the fracture resistance of the PPA modified mixtures is worse than that of the SBS modified mixtures. However, for those modified mixtures that use the PPA substituting part of the SBS modifier, a relatively low-temperature fracture resistance can be obtained compared with the mixture only using the SBS modifier.展开更多
以船用A36钢板为试验材料,开展紧凑拉伸试验裂纹尖端张开位移δ(crack tip opening displacement,CTOD)的双引伸计测试方法研究。结果显示,采用双引伸计方法可直接测定旋转因子r及δ,计算得到名义应力σ与裂纹尖端张开位移塑性分量δp(p...以船用A36钢板为试验材料,开展紧凑拉伸试验裂纹尖端张开位移δ(crack tip opening displacement,CTOD)的双引伸计测试方法研究。结果显示,采用双引伸计方法可直接测定旋转因子r及δ,计算得到名义应力σ与裂纹尖端张开位移塑性分量δp(plastic component of CTOD)的相关性曲线。与国标GB/T 21143—2007测试方法相比,双引伸计法对δp的测试精度更高;与EPRI(Electronic Power Research Institute)计算方法相比,双引伸计法对σ—δp关系曲线的确定更为直接可靠。展开更多
基金The National Natural Science Foundation of China(No.51278060)
文摘In order to determine whether polyphosphoric acid (PPA) can partially or completely substitute styrene-butadiene- styrene (SBS) modifier while it does not adversely affect the resistance to thermal cracking of the asphalt mixture, the low- temperature fracture properties of the PPA modified mixtures are evaluated and compared to the SBS modified mixtures. First, laboratory compacted test samples were tested by the indirect tensile test (IDT) and the newly developed fracture testing protocol, named as disk-shaped compact tension (DCT). Then, the effects of the test temperature and air-void ratio on the low-temperature fracture properties of asphalt mixtures were analyzed. The results show that the fracture resistance of the PPA modified mixtures is worse than that of the SBS modified mixtures. However, for those modified mixtures that use the PPA substituting part of the SBS modifier, a relatively low-temperature fracture resistance can be obtained compared with the mixture only using the SBS modifier.
文摘以船用A36钢板为试验材料,开展紧凑拉伸试验裂纹尖端张开位移δ(crack tip opening displacement,CTOD)的双引伸计测试方法研究。结果显示,采用双引伸计方法可直接测定旋转因子r及δ,计算得到名义应力σ与裂纹尖端张开位移塑性分量δp(plastic component of CTOD)的相关性曲线。与国标GB/T 21143—2007测试方法相比,双引伸计法对δp的测试精度更高;与EPRI(Electronic Power Research Institute)计算方法相比,双引伸计法对σ—δp关系曲线的确定更为直接可靠。