نتایج جستجو برای: critical hydraulic gradient

تعداد نتایج: 628141  

Journal: :تحقیقات آب و خاک ایران 0
خالد سلطان نژاد دانشجوی کارشناسی ارشد سازه‏های آبی، گروه آبیاری و آبادانی دانشگاه تهران علی رئیسی استبرق استادیار گروه آبیاری و آبادانی دانشگاه تهران جمال عبدالهی بیک مربی گروه آبیاری و آبادانی دانشگاه تهران محمدحسین امید استاد گروه آبیاری و آبادانی دانشگاه تهران

piping sometimes is occurred due to seepage of water in hydraulic structures. the continuty of this phenomenon decreases the safety or caused the failure of a structure. in this work, experimental tests were carried out on statically compacted natural and randomly reinforced silt sandy soil samples. the randomly reinforced samples were prepared with different lengths and percentages of an artif...

2014
Michalis Fragiadakis Savvas Xanthos Demetrios G. Eliades Anastasis Gagatsis Symeon Christodoulou

Presented herein is a methodology for the seismic and hydraulic assessment of the re-liability of urban water distribution networks (UWDN) based on general seismic assessment standards, as per the American Lifelines Alliance (ALA) guidelines, localized historical records of critical risk-of-failure metrics pertaining to the specific UWDN under assessment, and hydraulic simulations using adapted...

2015
Samantha K. Caldwell Marc Peipoch H. Maurice Valett

On riverine flood plains, reorganization by fluvial processes creates and maintains a mosaic of aquatic and riparian landscape elements across a biophysical gradient of disturbance and succession. Across flood plains of gravel-bottom rivers, spring brooks emerge from points of groundwater discharge that may occur in distinct landscape positions. We investigated how ecosystem processes in spring...

2016
Daoqian Chen Beibei Cao Shiwen Wang Peng Liu Xiping Deng Lina Yin Suiqi Zhang

Although silicon (Si) has been widely reported to alleviate plant nutrient deficiency, the underlying mechanism in potassium (K) deficiency is poorly understood. In this study, sorghum seedlings were treated with Si under a K deficiency condition for 15 days. Under control conditions, plant growth was not affected by Si application. The growth and water status were reduced by K-deficient stress...

Journal: :Plant, cell & environment 2006
Catherine E Lovelock Marilyn C Ball Brendan Choat Bettina M J Engelbrecht N Michelle Holbrook Ilka C Feller

Spatial gradients in mangrove tree height in barrier islands of Belize are associated with nutrient deficiency and sustained flooding in the absence of a salinity gradient. While nutrient deficiency is likely to affect many parameters, here we show that addition of phosphorus (P) to dwarf mangroves stimulated increases in diameters of xylem vessels, area of conductive xylem tissue and leaf area...

Journal: :International Journal of Integrated Engineering 2023

Subsurface drainage is part of a sustainable system's components. This component represents the infiltration stormwater into subsurface system for flow attenuation purposes. study examines parameters The laboratory validation perforated drains was conducted at longitudinal slope gradient 1/500 with Gate Fully Open. manning, n data obtained in these experiments varies several hydraulic parameter...

The nonlinear solvers in numerical solution of water flow in variably saturated soils are prone to convergence difficulties. Many aspects can give rise to such difficulties, like very dry initial conditions, a steep pressure gradient and great variation of hydraulic conductivity occur across the wetting front during the infiltration of water.  So, the averaging method applied to compute hydraul...

Thermo-Elasto-Plastic analyses of thick-walled spherical tanks made of functionally graded materials are investigated analytically. These tanks are subjected to positive or negative temperature gradient and internal pressure loadings separately or simultaneously. The power law modeling has been used for through-the-thickness variation of mechanical properties. von Mises yield criterion and Elas...

Journal: :international journal of civil engineering 0
h. khalili shayan irrigation and reclamation engineering dept., university of tehran, p.o. box 31587-4111, karaj, iran 31587-77871 e. amiri-tokaldany dept. of irrigataion and reclamation engineering, faculty of agriculture and engineering technology, university college of agriculture and natural resources, university of tehran

upstream blankets, drains and cutoff walls are considered as effective measures to reduce seepage, uplift pressure and exit gradient under the foundation of hydraulic structures. to investigate the effectiveness of these measures, individually or in accordance with others, a large number of experiments were carried out on a laboratory model. to extend the investigation for unlimited arrangement...

2016
John E. Gilley Gregory D. Boone David B. Marx J. E. Gilley G. D. Boone D. B. Marx

Beef cattle feedlots contain unconsolidated surface material that accumulates within feedlot pens during a feeding cycle. Runoff from feedlot surfaces is diverted into settling basins. The storage capacity of the settling basins will be substantially reduced if large quantities of solid material are transported in runoff from the feedlot surfaces. The objective of this study was to identify the...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید