Rubble deposits with a high concentration of rock debris were created after the powerful earthquakes in Jiuzhaigou.Because of the restricted soil resources,water leaks,and nutrient deficits,these deposits pose serious...Rubble deposits with a high concentration of rock debris were created after the powerful earthquakes in Jiuzhaigou.Because of the restricted soil resources,water leaks,and nutrient deficits,these deposits pose serious obstacles for vegetation regeneration.The purpose of this study was to investigate the main mechanisms controlling soil water retention and evaluate the effects of different amendments on the hydraulic characteristics and water-holding capacity of collapsed rubble soils.Finegrained soil,forest humus,crushed straw,and organic components that retain water were added to the altered soils to study the pore structure images and soil-water characteristic curves.Comparing understory humus to other supplements,the results showed a considerable increase in the soil's saturated and wilting water content.The saturated water content and wilting water content rose by 17.9%and 4.3%,respectively,when the percentage of understory soil reached 30%.Additionally,the enhanced soil's microporosity and total pore volume increased by 45.33%and 11.27%,respectively,according to nuclear magnetic imaging.It was shown that while clay particles and organic matter improved the soil's ability to adsorb water,they also increased the soil's total capacity to store water.Fine particulate matter did this by decreasing macropores and increasing capillary pores.These results offer an essential starting point for creating strategies for soil repair that would encourage the restoration of plants on slopes that have been damaged.展开更多
Crumble rubber(CR)can be used to prepare CR and styrene-butadiene-styrene(SBS)composite modified asphalt with a good high-and low-temperature performance,meanwhile the addition of CR could work as the substitute for S...Crumble rubber(CR)can be used to prepare CR and styrene-butadiene-styrene(SBS)composite modified asphalt with a good high-and low-temperature performance,meanwhile the addition of CR could work as the substitute for SBS and help reduce the content of SBS.This study contains three main parts:effect of preparation and effect of material composition as well as rheological performance characterization.Factors during the preparation,including shearing temperature,shearing time,mixing time and swelling time,were selected,while base binder,CR content,CR particle size and SBS content in material composition were considered.The effects of these factors were assessed in terms of the conventional performance(penetration,softening point,ductility and storage stability).After identifying these effects,the sample of CR and SBS modified asphalt at the selected preparing condition and material composition(CR/SBSMA)was made,and the corresponding SBS modified and CR modified asphalt(SBSMA and CRMA)were produced for the comparing reason.Subsequently,temperature sweeps from 0℃ to 80℃ were utilized to depict the viscoelasticity of these modified asphalt binders by complex modulus and phase angle.Multiple stress creep recovery tests(MSCR)at 64℃ and bending beam rheometer tests(BBR)at various low temperatures were employed to evaluate the high-and low-temperature performance,respectively.Results highlight that that CR/SBSMA could exhibit an excellent high-temperature performance(better than SBSMA),and a good low-temperature performance(reaching the level of base binder).展开更多
基金jointly funded by the Sichuan Provincial Natural Science Foundation of China(Grant No.2023NSFSC0378)the Jiuzhaigou Lake Swamp and River Ecological Restoration Research Project(N5132112022000246)the Research base and Support provided by Jiuzhaigou Administration for this study。
文摘Rubble deposits with a high concentration of rock debris were created after the powerful earthquakes in Jiuzhaigou.Because of the restricted soil resources,water leaks,and nutrient deficits,these deposits pose serious obstacles for vegetation regeneration.The purpose of this study was to investigate the main mechanisms controlling soil water retention and evaluate the effects of different amendments on the hydraulic characteristics and water-holding capacity of collapsed rubble soils.Finegrained soil,forest humus,crushed straw,and organic components that retain water were added to the altered soils to study the pore structure images and soil-water characteristic curves.Comparing understory humus to other supplements,the results showed a considerable increase in the soil's saturated and wilting water content.The saturated water content and wilting water content rose by 17.9%and 4.3%,respectively,when the percentage of understory soil reached 30%.Additionally,the enhanced soil's microporosity and total pore volume increased by 45.33%and 11.27%,respectively,according to nuclear magnetic imaging.It was shown that while clay particles and organic matter improved the soil's ability to adsorb water,they also increased the soil's total capacity to store water.Fine particulate matter did this by decreasing macropores and increasing capillary pores.These results offer an essential starting point for creating strategies for soil repair that would encourage the restoration of plants on slopes that have been damaged.
基金This study is jointly found by the Natural Science Foundation of Jiangxi Province of China(20202BABL214046)the Natural Science Foundation of Xinjiang Uygur Autonomous Region(2020D01A92)+1 种基金the China Postdoctoral Foundation(2020M683709XB)the Research Project of China Railway City Development&Investment Group Co.Ltd.
文摘Crumble rubber(CR)can be used to prepare CR and styrene-butadiene-styrene(SBS)composite modified asphalt with a good high-and low-temperature performance,meanwhile the addition of CR could work as the substitute for SBS and help reduce the content of SBS.This study contains three main parts:effect of preparation and effect of material composition as well as rheological performance characterization.Factors during the preparation,including shearing temperature,shearing time,mixing time and swelling time,were selected,while base binder,CR content,CR particle size and SBS content in material composition were considered.The effects of these factors were assessed in terms of the conventional performance(penetration,softening point,ductility and storage stability).After identifying these effects,the sample of CR and SBS modified asphalt at the selected preparing condition and material composition(CR/SBSMA)was made,and the corresponding SBS modified and CR modified asphalt(SBSMA and CRMA)were produced for the comparing reason.Subsequently,temperature sweeps from 0℃ to 80℃ were utilized to depict the viscoelasticity of these modified asphalt binders by complex modulus and phase angle.Multiple stress creep recovery tests(MSCR)at 64℃ and bending beam rheometer tests(BBR)at various low temperatures were employed to evaluate the high-and low-temperature performance,respectively.Results highlight that that CR/SBSMA could exhibit an excellent high-temperature performance(better than SBSMA),and a good low-temperature performance(reaching the level of base binder).
