A flume experiment was conducted to investigate the restratification of liquefied sediment strata under a wave load with the focus on the interbedded strata of coarse and fine sediments formed in estuarine and coastal...A flume experiment was conducted to investigate the restratification of liquefied sediment strata under a wave load with the focus on the interbedded strata of coarse and fine sediments formed in estuarine and coastal areas.The aim of this research was to study the characteristics and processes of liquefied sediment strata in terms of wave-induced liquefaction.In the experiment,the bottom bed liquefied under the wave action and the liquefied soil moved in the same period with the overlying waves,and the track of the soil particles in the liquefied soil was an ellipse.The sand layer consisting of coarse particles in the upper part,settled into the lower silt layer.The sinking of coarse particles and upward migration of the fine particles of the lower layer induced by liquefied sediment fluctuations are the likely reasons for sedimentation of the sand layer in liquefied silt.展开更多
The release of intracellular water during degradation process contributes to the great leachate production and settlement of landfilled high kitchen waste content MSW(HKWC-MSW). An oven-drying and absorbent-paper comb...The release of intracellular water during degradation process contributes to the great leachate production and settlement of landfilled high kitchen waste content MSW(HKWC-MSW). An oven-drying and absorbent-paper combined method was proposed to measure the intracellular and interparticle water contents of HKWC-MSW. Two degradation experiments were carried out to study the release process of intracellular water and its effect on the hydro-mechanical behaviors of HKWC-MSW.It was found that the two degradation experiments showed similar degradation behaviors with BOD/COD decreasing with time in the early stage. In the first degradation experiment, most intracellular water was released during the first two months, and the degradation of degradable matter in kitchen waste(KW) was much slower than the release process of intracellular water. The particle size became smaller and the overall grain specific gravity increased during the fast release process of intracellular water.In the second degradation experiment, after two-year degradation, the total leachate production was about 45.2% of the initial wet weight of HKWC-MSW specimen. Water retention capacity θ_f increased from 0.23 to 0.58 during 1–69 d, which might be caused by the decrease of particle size and compression of waste skeleton. As almost all the intracellular water was released after 80-day degradation, during the latter stage of leachate drainage under gravity, θ_f decreased and was close to the total volumetric water content. The total compression strain was about 0.39. The secondary compression strain during 1–80 d(i.e., about 0.07)was considered to be mainly resulted by the release of intracellular water and the subsequent drainage of leachate, and it accounted for about 22.6% of the total secondary compression strain.展开更多
The differences between the formation processes of lab backfill samples and field backfill were analysed. An improved sampling mold, containing an outer box shell and inner sampling mold, was put forward. The new and ...The differences between the formation processes of lab backfill samples and field backfill were analysed. An improved sampling mold, containing an outer box shell and inner sampling mold, was put forward. The new and traditional test molds were applied to make subsequent-backfill samples of Yong-ping Copper Mine. The observation of mass fraction and theory analysis of settlement and distribution of tailing particles were carried out. The research results show that the magnitude of the strength of the backfill forming in new mold is lower than that of backfill forming in traditional mold, and the biggest gap amounts to 36%.展开更多
基金The funding for this project was provided by the National Natural Science Foundation of China(No.41976049)the Fundamental Research Funds for the Central Universities(No.202061028).
文摘A flume experiment was conducted to investigate the restratification of liquefied sediment strata under a wave load with the focus on the interbedded strata of coarse and fine sediments formed in estuarine and coastal areas.The aim of this research was to study the characteristics and processes of liquefied sediment strata in terms of wave-induced liquefaction.In the experiment,the bottom bed liquefied under the wave action and the liquefied soil moved in the same period with the overlying waves,and the track of the soil particles in the liquefied soil was an ellipse.The sand layer consisting of coarse particles in the upper part,settled into the lower silt layer.The sinking of coarse particles and upward migration of the fine particles of the lower layer induced by liquefied sediment fluctuations are the likely reasons for sedimentation of the sand layer in liquefied silt.
基金supported by the National Basic Research Program of China(Grant No.2012CB719800)the National Natural Science Foundation of China(Grant Nos.51708508,41402249)the Zhejiang Provincial Natural Science Foundation(Grant Nos.LY17E080021,LY15E080021)
文摘The release of intracellular water during degradation process contributes to the great leachate production and settlement of landfilled high kitchen waste content MSW(HKWC-MSW). An oven-drying and absorbent-paper combined method was proposed to measure the intracellular and interparticle water contents of HKWC-MSW. Two degradation experiments were carried out to study the release process of intracellular water and its effect on the hydro-mechanical behaviors of HKWC-MSW.It was found that the two degradation experiments showed similar degradation behaviors with BOD/COD decreasing with time in the early stage. In the first degradation experiment, most intracellular water was released during the first two months, and the degradation of degradable matter in kitchen waste(KW) was much slower than the release process of intracellular water. The particle size became smaller and the overall grain specific gravity increased during the fast release process of intracellular water.In the second degradation experiment, after two-year degradation, the total leachate production was about 45.2% of the initial wet weight of HKWC-MSW specimen. Water retention capacity θ_f increased from 0.23 to 0.58 during 1–69 d, which might be caused by the decrease of particle size and compression of waste skeleton. As almost all the intracellular water was released after 80-day degradation, during the latter stage of leachate drainage under gravity, θ_f decreased and was close to the total volumetric water content. The total compression strain was about 0.39. The secondary compression strain during 1–80 d(i.e., about 0.07)was considered to be mainly resulted by the release of intracellular water and the subsequent drainage of leachate, and it accounted for about 22.6% of the total secondary compression strain.
基金Project(2010CB732004) Supported by the National Basic Research Program of ChinaProject(50934006) supported by the Key Project of Science and Technology of Shanghai+1 种基金 ChinaProject(CX2012B073) supported by Doctoral Candidates' Scientific Research Innovation Program of Hunan Province, China
文摘The differences between the formation processes of lab backfill samples and field backfill were analysed. An improved sampling mold, containing an outer box shell and inner sampling mold, was put forward. The new and traditional test molds were applied to make subsequent-backfill samples of Yong-ping Copper Mine. The observation of mass fraction and theory analysis of settlement and distribution of tailing particles were carried out. The research results show that the magnitude of the strength of the backfill forming in new mold is lower than that of backfill forming in traditional mold, and the biggest gap amounts to 36%.
