期刊文献+
共找到7篇文章
< 1 >
每页显示 20 50 100
流砂型积水坑施工
1
作者 龙清波 《建厂科技交流》 1997年第2期15-16,共2页
关键词 建筑工程 流砂型 积水坑 工程施工
原文传递
Applications of GSTARS Computer Models for Solving River and Reservoir Sedimentation Problems 被引量:2
2
作者 YANG Chih Ted 《Transactions of Tianjin University》 EI CAS 2008年第4期235-247,共13页
GSTARS (Generalized Sediment Transport model for Alluvial River Simulation) is a series of computer models developed by the U.S. Bureau of Reclamation while the author was employed by that agency. The stream tube conc... GSTARS (Generalized Sediment Transport model for Alluvial River Simulation) is a series of computer models developed by the U.S. Bureau of Reclamation while the author was employed by that agency. The stream tube concept is used in all GSTARS models which allow us to solve one-dimensional equations for each stream tube independently and obtain semi-two-dimensional variation of the hydraulic conditions along and across stream tubes for rivers and reservoirs. Sedi-ment transport, scour, and deposition processes are simulated along each stream tube independently to give us a semi-three-dimensional variation of the bed geometry. Most sediment transport computer models assume that channel width is given and cannot change during the simulation process. GSTARS models apply the theory of minimum stream power to the determination of optimum channel width and channel geometry. The concepts of channel side stability, and active, inactive, and armoring layers are used in all GSTARS models for realistic long-term simulation and prediction of the scour and deposition processes in rivers and reservoirs.GSTARS models have been applied in many countries for solving a wide range of river and reservoir sedimentation problems. Case studies will be used to illustrate the applications of GSTARS computer models. 展开更多
关键词 computer model RESERVOIR RIVER sediment transport
下载PDF
River Morphology and River Channel Changes 被引量:1
3
作者 CHANG Howard H 《Transactions of Tianjin University》 EI CAS 2008年第4期254-262,共9页
River morphology has been a subject of great challenge to scientists and engineers who recognize that any effort with regard to river engineering must be based on a proper understanding of the morphological features i... River morphology has been a subject of great challenge to scientists and engineers who recognize that any effort with regard to river engineering must be based on a proper understanding of the morphological features involved and the responses to the imposed changes. In this paper, an overview of river morphology is presented from the geomorphic viewpoint. Included in the scope are the regime concept, river channel classification, thresholds in river morphology, and geomorphic analysis of river responses. Analytical approach to river morphology based on the physical principles for the hydraulics of flow and sediment transport processes is also presented. The application of analytical river morphology is demonstrated by an example. Modeling is the modern technique to determine both short-term and long-term river channel responses to any change in the environment. The physical foundation of fluvial process-response must be applied in formatting a mathematical model. A brief introduction of the mathematical model FLUVIAL-12 is described. 展开更多
关键词 river morphology sediment transport river types mathematical model
下载PDF
Statistical modelling for effect of mix-parameters on properties of high-flowing sand-concrete 被引量:7
4
作者 T.BOUZIANI A.BENMOUNAH M.BDRINA 《Journal of Central South University》 SCIE EI CAS 2012年第10期2966-2975,共10页
The high-flowing sand-concrete (HFSC) containing natural sands as aggregate was carried out. The high fluidity and stability of HFSC can be achieved by tailoring the mix design parameters, such as fine to coarse san... The high-flowing sand-concrete (HFSC) containing natural sands as aggregate was carried out. The high fluidity and stability of HFSC can be achieved by tailoring the mix design parameters, such as fine to coarse sand ratio, dosage of additions, water to binder ratio and dosage of admixtures. Mini-cone slump test, v-fl.mnel time test and viscosity model parameters were used to characterize the behaviour of HFSC in fresh state. The mechanical compressive strength in 28 d was also determined. A factorial design approach was used to establish models highlighting the effect of each mix-parameter on measured properties of HFSC. The derived models are valid for mixtures made with 0 to 0.3 of dune sand to total sand ratio, 82 to 418 kg/m3 of marble powder, 0.42 to 0.46 of water/binder ratio and 1.3% to 1.9% of superplasticizer high water-reducer. The results show that the derived models constitute very efficient means for understanding the influence of key mix-parameters on HFSC properties and are useful in selecting the optimum mix proportions, by simulating their impact on fluidity, stability and compressive strength. 展开更多
关键词 high-flowing sand-concrete factorial design FLUIDITY VISCOSITY mix-design parameters
下载PDF
Theoretical Predictions of Migration Probabilities of Liquid- Liquid Hydrocyclones Separating Light Dispersions 被引量:7
5
作者 赵庆国 马重芳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第2期183-189,共7页
Based on Bloor & Ingham's approach for determining the fluid fieldand on the analyses of loci of fluid particles inside hydrocyclones,analytical models are developed for calculating the migrationprobability of... Based on Bloor & Ingham's approach for determining the fluid fieldand on the analyses of loci of fluid particles inside hydrocyclones,analytical models are developed for calculating the migrationprobability of single-cone and two-cone hydrocyclones separatinglight dispersions. The calculated results are in good agreement withThew's correlation at different flow rate, split ratio or fluidproperties if the structural parameters keep the same as those ofThew's 35 mm hydrocyclone. The difference between predictionsaccording to two-cone model and single-cone model is nearlynegligible, which is very close to thew's original idea that majorseparation happens in the small cone-angle zone. 展开更多
关键词 HYDROCYCLONE theoretical model migration probability
下载PDF
Paste-like cemented backfilling technology and rheological characteristics analysis based on jigging sands 被引量:1
6
作者 魏冲 王新民 +1 位作者 张云海 张钦礼 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第1期155-167,共13页
To make backfilling body meet strength requirement,physical-chemical evaluation and proportioning tests were conducted on several backfilling materials.Jigging sands,#32.5 cement and fly ash were determined as backfil... To make backfilling body meet strength requirement,physical-chemical evaluation and proportioning tests were conducted on several backfilling materials.Jigging sands,#32.5 cement and fly ash were determined as backfilling aggregate,binding material and modified material,respectively.An optimized proportion of backfilling materials with a solid mass fraction of 78%and cement:fly ash:jigging sands mass ratio of 1:2:14,was suggested to Jiangan Pyrite Mine,China.The slurry made by optimized proportion produced obvious shear thinning phenomena,and was confirmed as paste-like slurry.To analyze its rheological characteristics,L-type pipeline test and Haake VT550 rotational viscometer test were conducted.Bingham and Casson fluid models were applied to several paste-like slurry samples to simulate flow and stress states;Casson fluid model was proved to have better simulation effect on paste-like slurry with shear thinning phenomena;rheological parameters of backfilling slurry made by suggested proportion were measured.Initial yield stress,average apparent viscosity and limiting viscosity are 55.35 Pa,1.216 Pa-s and 0.48 Pa-s,respectively.Compared with Bingham fluid model,Casson fluid model has a better simulation effect on paste-like slurry with shear thinning phenomena,through calculating the residual standard deviations. 展开更多
关键词 paste-like slurry jigging sands shear thinning Casson fluid model backfilling system
下载PDF
Rheology of Cement Mortars with Crushed Fine Aggregates of Different Lithological Types
7
作者 Elton Bauer Carla Cristina Nascimento Santos Pereira +2 位作者 Joao Henrique da Silva Rego Claudio Henrique deAlmeida Feitosa Pereira Eliane Kraus Castro 《Journal of Civil Engineering and Architecture》 2014年第9期1110-1120,共11页
Crushed fine aggregates are widely used for full or partial replacement of natural sands in concretes. The crushed sands present different characteristics from the natural sand, especially if taking into account the c... Crushed fine aggregates are widely used for full or partial replacement of natural sands in concretes. The crushed sands present different characteristics from the natural sand, especially if taking into account the content of microfine particle, the distribution of particle sizes, the shape features, besides the different lithological origin. From the rheological point of view, the crushed sands frequently provide mixtures with high yield stress, high viscosity, high cohesion and internal friction, which hinders its use in concrete. This study is focused on the evaluation of the rheological behavior of concrete mortar phase when using different lithological types of crushed sand in total replacement of natural sand. The lithological types surveyed were granite, calcitic limestone, dolomite limestone and mica schist. Each of these sand types was studied in two ways: in natura and with adjusted grading curve. The results show the best performance of calcitic limestone providing lower viscosities and lower yield stress in mortars. 展开更多
关键词 Crushed fine aggregate RHEOLOGY MORTAR LITHOLOGY particle shape particle size distribution.
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部