Freeze-thaw damage is the most common disease of semi-rigid bases in cold regions, which may greatly affect the dura- bility of roadways. In this study, the compressive strength and frost resistance of four different ...Freeze-thaw damage is the most common disease of semi-rigid bases in cold regions, which may greatly affect the dura- bility of roadways. In this study, the compressive strength and frost resistance of four different types of semi-rigid bases (lime-fly ash-stabilized sand, cement-stabilized sand, lime-fly ash-stabilized gravel, and cement-stabilized gravel) are assessed by varying the materials content. Based on freeze-thaw and compressive strength tests, this paper presents the performance of the different materials, each having different physical properties, and the optimal amounts of materials contents are proposed.展开更多
Compressive strength and compressive resilience modulus are two important parameters to measure the mechanical properties of semi-rigid base.The test methods of semi-rigid base cores are different from those of the la...Compressive strength and compressive resilience modulus are two important parameters to measure the mechanical properties of semi-rigid base.The test methods of semi-rigid base cores are different from those of the laboratory samples in terms of sample acquisition,sample selection and humidity requirements.Core-drilling location,size of core sample,smoothness and humidity conditions were analyzed.The test methods of compressive strength and compressive resilience modulus were proposed.The research results show that compressive strength of lime fly-ash stabilized gravels base has a tendency of increasing during a long period.The compressive resilience modulus increases significantly with compressive strength of semi-rigid base.The compressive resilience modulus generally is 3-4 times than the recommended range of asphalt pavement design specifications.The fluctuation range of compressive resilience modulus is obviously higher than the compressive strength.The compressive resilience modulus is more sensitive to the construction variability.The overall trend between the compressive resilience modulus and the back-calculation modulus is consistent.FWD(falling weight deflectometer)back-calculation modulus can reflect the stiffness and bearing capacity of asphalt pavement.展开更多
In order to compare the impact of thickness of different layers on fatigue lives of different semi-rigid asphalt pavement structures, the mechanical results from finite element models in ABAQUS are incorporated with t...In order to compare the impact of thickness of different layers on fatigue lives of different semi-rigid asphalt pavement structures, the mechanical results from finite element models in ABAQUS are incorporated with the fatigue results from fatigue models in FE-SAFE to calculate the mechanical response and fatigue lives of semi-rigid pavement structures under heavy traffic loads. Then the influences on fatigue lives caused by the changes in the thickness of layers in pavement structures are also evaluated. The numerical simulation results show that the aggregated base and the large stone porous mixture (LSPM) base have better anti-cracking performance than the conventional semi-rigid base. The appropriate thickness range for the aggregated layer in the aggregated base is 15 to 18 cm. The thickness of the LSPM layer in the LSPM base is recommended to be less than 15 cm.展开更多
Based on the 2006 Chinese asphalt pavement deflection value design index, we used KENLAYER Pavement Analysis and Design software and lstOpt statistical analysis software to can-y on the nonlinear regression, this pape...Based on the 2006 Chinese asphalt pavement deflection value design index, we used KENLAYER Pavement Analysis and Design software and lstOpt statistical analysis software to can-y on the nonlinear regression, this paper establish high-grade highway design equations for the compressive slrain of soil sub-base top (CSSBT) and the radial compressive stress of semi-rigid base top (RCSRBT). The correlation coefficients inspection standard to get precise proof, which means that our granular base design equations have high credibility and can be used in the Chinese design index of asphalt pavement with granular base (APGB).展开更多
基金supported by the National Natural Science Foundation of China (Nos. 51378057 and 41371081)
文摘Freeze-thaw damage is the most common disease of semi-rigid bases in cold regions, which may greatly affect the dura- bility of roadways. In this study, the compressive strength and frost resistance of four different types of semi-rigid bases (lime-fly ash-stabilized sand, cement-stabilized sand, lime-fly ash-stabilized gravel, and cement-stabilized gravel) are assessed by varying the materials content. Based on freeze-thaw and compressive strength tests, this paper presents the performance of the different materials, each having different physical properties, and the optimal amounts of materials contents are proposed.
文摘Compressive strength and compressive resilience modulus are two important parameters to measure the mechanical properties of semi-rigid base.The test methods of semi-rigid base cores are different from those of the laboratory samples in terms of sample acquisition,sample selection and humidity requirements.Core-drilling location,size of core sample,smoothness and humidity conditions were analyzed.The test methods of compressive strength and compressive resilience modulus were proposed.The research results show that compressive strength of lime fly-ash stabilized gravels base has a tendency of increasing during a long period.The compressive resilience modulus increases significantly with compressive strength of semi-rigid base.The compressive resilience modulus generally is 3-4 times than the recommended range of asphalt pavement design specifications.The fluctuation range of compressive resilience modulus is obviously higher than the compressive strength.The compressive resilience modulus is more sensitive to the construction variability.The overall trend between the compressive resilience modulus and the back-calculation modulus is consistent.FWD(falling weight deflectometer)back-calculation modulus can reflect the stiffness and bearing capacity of asphalt pavement.
基金The National Natural Science Foundation of China(No.51378121)
文摘In order to compare the impact of thickness of different layers on fatigue lives of different semi-rigid asphalt pavement structures, the mechanical results from finite element models in ABAQUS are incorporated with the fatigue results from fatigue models in FE-SAFE to calculate the mechanical response and fatigue lives of semi-rigid pavement structures under heavy traffic loads. Then the influences on fatigue lives caused by the changes in the thickness of layers in pavement structures are also evaluated. The numerical simulation results show that the aggregated base and the large stone porous mixture (LSPM) base have better anti-cracking performance than the conventional semi-rigid base. The appropriate thickness range for the aggregated layer in the aggregated base is 15 to 18 cm. The thickness of the LSPM layer in the LSPM base is recommended to be less than 15 cm.
基金supported by the Singapore Government Foundation Project under the Nan Yang Technological University Transport Research Team Program (No. CTG/09-398)the Chinese Science Technology Foundation Project of Yunnan (No. TST477126A)
文摘Based on the 2006 Chinese asphalt pavement deflection value design index, we used KENLAYER Pavement Analysis and Design software and lstOpt statistical analysis software to can-y on the nonlinear regression, this paper establish high-grade highway design equations for the compressive slrain of soil sub-base top (CSSBT) and the radial compressive stress of semi-rigid base top (RCSRBT). The correlation coefficients inspection standard to get precise proof, which means that our granular base design equations have high credibility and can be used in the Chinese design index of asphalt pavement with granular base (APGB).