SUMMARYThe Mindlin-Reissner finite strip method is used to study in a qualitative manner boundary layer effects in uniform and variable-thickness plates with rectangular and curved planforms.
A morning glory spillway usually has an ogee shaped crest and conveys spill water flow to its downstream vertical shaft followed by a horizontal tunnel. The ungated morning glory spillways should convey variable discharges, which nonlinearly depends on the reservoir water elevation. The variation of discharge for unit length of the crest may cause challenges on design of downstream crest curve (which affects coefficient of discharge and downstream crest negative pressure). Furthermore, formation of a horizontal vortex flow affects the spillway discharge. In this paper, in order to resolve these problems by energy dissipation and water flow aeration, variable size steps are mapped to downstream of the curved ogee crest of morning glory spillway. A finite volume base numerical flow solver is used to investigate the effects of the considered configurations on the hydraulic design parameters. In this work, having verified the pressure and aeration of the flow over an ordinary stepped spillway, the characteristics of flow over geometry of an ordinary morning glory spillway, as well as stepped spillway, are modelled and compared to the available measurements on laboratory hydraulic models. Finally, an existing ordinary morning glory spillway is computationally modelled by considering an alternative design of variable sized steps at downstream crest (by mapping their edges to the ordinary profile of the morning glory spillway). The stepped morning glory spillway alternatives are numerically simulated for various flow rates, and the computed discharge coefficients and energy dissipations are compared with simulation results for ordinary morning glory spillway of the case.
Artificial cementation is a method commonly used to enhance and improve soil properties. This paper investigates the effect of using different amounts of cement on soil strength parameters and soil bearing capacity, using the finite element method. Experimental tests are conducted on soil samples with different amounts of Portland cement. A 2-D numerical model is created and validated using the numerical modelling software, COMSOL Multiphysics 5.6 software. The study finds that the cohesion, and the angle of the internal friction of the soil samples increase significantly as a result of adding 1%, 2%, and 4% of Portland cement. The results demonstrate that the stresses and strain under the strip footing proposed decrease by 3.24% and 7.42%. Moreover, the maximum displacement also decreases by 1.47% and 2.97%, as a result of adding cements of 2% and 4%. The bearing capacity values obtained are therefore excellent, especially when using the 2% and 4% cement. The increase identified is due to the increased values of the bearing capacity factors. It is concluded that from an economic viewpoint, using 2% cement is the best option.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.