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Hydrological effects of plant on matric suction
Published in Charles W. W. Ng, Anthony K. Leung, Junjun Ni, Plant–Soil Slope Interaction, 2019
Charles W. W. Ng, Anthony K. Leung, Junjun Ni
To apply rainfall events with different intensities and durations (i.e., to control P in Eq. [1.6]) during a test, the rainfall simulation system installed in the plant room was used. This system consists of 10 plastic tubes, each 20 mm in diameter. Each tube is drilled with holes 1 mm in diameter to allow water to be discharged as rainfall. The simulator is mounted on two support stands at a specified height (Figure 2.3) above the soil surface. It is connected to a water reservoir with a capacity of 2 L for maintaining a constant difference in hydraulic head. By adjusting the height of the rainfall simulator relative to the water reservoir, a constant rainfall intensity can be maintained. A flow meter with an accuracy of ±0.5 L/h is attached to the device so that any desired water discharge rate (i.e., rainfall intensity) and discharge duration (i.e., rainfall duration) can be applied during testing. By controlling P and measuring surface runoff (Roff), the amount of water infiltration (Rin) is known. While water retained in soil (ΔWsoil) can be estimated from the measurements of soil moisture, the amount of root water uptake by plants (Rplant) can be determined via the water balance calculation given by Eq. (1.6).
Measuring stiffness of soils in situ
Published in Fusao Oka, Akira Murakami, Ryosuke Uzuoka, Sayuri Kimoto, Computer Methods and Recent Advances in Geomechanics, 2014
Fusao Oka, Akira Murakami, Ryosuke Uzuoka, Sayuri Kimoto
The infiltration and evaporation tests were conducted using an acrylic column of 1m height and 0.19m in internal diameter. The column setup has been described in detail by Yang et al. (2004). The column was equipped with tensiometer-transducer system (Soil Moisture-2100F and ICT-GT3-15, ICT International Pty Ltd), time-domain reflectometry (TDR) system (Trase System, Soil Moisture Corp) for water content measurement and weighing balance (UWE PS12-K) for water balance calculations. The rainfall was simulated using a rainfall simulator made using a custom-made plastic nozzle. Two layers of filter papers were placed on the soil surface to ensure uniformity of rainfall distribution on the soil surface. The water for the rainfall was supplied by a constant head tank. Constant head tank was used to ensure similar pressures were applied to the rainfall simulator. The excess water from the constant head tank was circulated back to the water storage tank to reduce water consumption. The water that drained from the bottom of the column was channeled to the percolation tank.
Measurement of Soil Erosion by Water
Published in Abrar Yousuf, Manmohanjit Singh, Watershed Hydrology, Management and Modeling, 2019
Direct measurements are perhaps the most accurate way of measuring soil erosion, but also the most laborious and time consuming. They involve collecting deposited materials and taking volumetric and weight measurements. It includes establishing bounded runoff plots to collect surface runoff, with a flow-collecting device at outlet. Detailed field studies to measure soil erosion are usually conducted for research purposes to study basic soil erosion processes or to evaluate the effect of soil conservation practices on soil erosion. These studies are either done under natural rainfall conditions or under artificial rainfall conditions using a rainfall simulator in the field or laboratory conditions.
Theoretical model to estimate the storage volume of rolled erosion control products/geomeshes
Published in The Journal of The Textile Institute, 2023
S. Suresh Kumar, Vinay Kumar Midha, Sushma Verma
Samples are subjected to simulated rainfall condition of 100 mm/hr in a runoff erosion control tester (bench-scale), which is designed based on ASTM D 7101 standards with certain modification in the ramp size (Figure 6(a)) (ASTM D 7101-13, 2013). Since geomeshes have open structures with larger mesh opening size, the test core of 20 cm diameter used in ASTM D7101 is substituted with ramp size of 50 cm length and 25 cm width (Midha & Suresh, 2013), to obtain reliable results. To avoid the influence of soil infiltration (absorption of water by soil) on storage effect (culmination discharge), testing is carried out at zero-infiltration condition (without soil), for which soil containers are replaced with a metallic ramp with uniform smooth surface (Figure 6(b)) (Kalibová et al., 2016). V-jet type rainfall simulators are used to simulate the required rainfall intensity (100 mm/hr). Water flow rate and pressure in the rainfall simulator is continuously monitored throughout the experiment, to ensure uniform rainfall simulation.
Identification and quantification of erosion on a sand tailings dam
Published in Geosystem Engineering, 2020
N. Slingerland, A. Sommerville, D. O’Leary, N.A. Beier
This research focusses on tailings dams constructed to hold (encapsulate) slurried mine waste, or ‘tailings’, in the Athabasca oil sands (AOS) and the erosion processes acting on them. Tailings dams are common in mining, and throughout the oil sands region. Tailings dams typically present the greatest inherent risk on a mine site, and this continues well after closure (ICOLD Committee on tailings dams, 2013). However, it has been previously noted that the geomorphology of mining landscapes is an area where few studies have focussed (Martin-Duque, Zapico, Oyarzum, Lopez-Garcia, & Cubas, 2015). The tendency of tailings sand-constructed dams to erode was documented in the 1970s (Rowell, 1979); however, little has been published on the subject since this time. Initially, soil stability investigations occurred to evaluate the impact of vegetation and fertilization on dam erosion (Rowell, 1979). Later, Sawatsky et al. (1996) used a rainfall simulator to apply multiple precipitation intensities to AOS sand tailings dams for periods less than 2 h to study erosion on plots with various degrees of reclamation. Most recently, McKenna (2002) conducted extensive laboratory and field flume testing of oil sands clay shale, regarding gully erosion and implications for the design of overburden-constructed landforms.
The behavior of permeable interlocking concrete pavement under different rainfall intensities and design conditions
Published in International Journal of Pavement Engineering, 2022
Tameem Mohammed Hashim, Thair J.M. Al-Fatlawi, Ahmed Awad Matr Al-Abody, Duaa Abdul Rida Musa, Mohammed Salah Nasr
Park DG. et al. (Park et al. (2014)) evaluated the capacity of PICP to store the infiltrated water using a rainfall simulator test. In addition, surface runoff, delay time, and outflows have been measured under 2 h as a rainfall period. Similarly, the ongoing study has also employed a rainfall simulator to configure the amount of infiltrated water, surface runoff, and load resistance of PICP under different geometrical slopes and rainfall intensities, adding new boundary conditions and service tests to the previous study.