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Experimental and Numerical Study of the Effect of PET Recycling Admixtures on Pore Water Pressure and Output Discharge in Homogeneous Earth Dams. Ahmad Zadeh Touri R., Pourbakhshian S., Pouraminian M. J. Civil Eng. Urban., 5(1): 31-34, 2015; pii:S225204301500007-5 Abstract This study analytically and experimentally investigates the leakage in homogenous earth dam (clay) reinforced by recycled PET. First, the effect of PET addition on permeability of clay in geotechnical laboratory is evaluated, according to the results of first step, a physical model of homogenous earth dam is prepared in laboratory flume, both in PETs or without PETs and measured the water height in dam body using piezometers installed on flume body and also leakage discharge was calculated. Third, phreatic line formed in the body of dam and the pore pressure of it was analyzed regarding the first and second phases. The impact of output discharge reduction on dam stability was also studied in software; PET addition impact on output discharge reduction was 23.14%. Discharge reduction lead to increase of dam stability. Keywords: Homogenous Earth Dam, Permeability Test, Physical Model, PLAXIS, PET [Full text-PDF] منبع: [Hidden Content] J. Civil Eng. Urban., 5 (1) 31-34, 2015.pdf

Effect of Wedge Shape Deflector on Dissipating Energy in Triangular Flip Buckets Original Article, C09 Mona Omidvarinia, S.H.Musavi Jahromi Journal. Civil Eng. Urban. 3(2): 56-61. 2013 Abstract: Ski jumps are a major element of each dam spillway because these are the only structures able to accomplish satisfactory energy dissipation for takeoff velocities in excess of some 20 m/ s. When water flows over spillways or the dam bottom outlets, flow has a height velocity. In such conditions it has a lot of kinetic energy. In order to dissipate this destructive energy, energy dissipater should be constructed. If geology condition in downstream is appropriate, flip bucket can be used, particularly for height dams. This structure to loss kinematic energy is a cheap method and safer than other ordinary energy dissipaters such as hydraulic basins and roller buckets to employ deflector, is one way to increase energy dissipation in this structure. Deflector is a wedge-shaped structure which creates changes in part of flow trajectory. To investigate the effect of deflector on energy dissipation, an experimental setup has been developed in the Hydraulic Laboratory of Shahid Chammran, Iran. In this research program, the 45 degree bucket with 7 cm approach channel at the end of ogee spillway was divided into two trajectories by deflector. Data analysis showed that the clash between these two trajectories increases energy dissipation in flip bucket. Maximum observed energy dissipation was 70.3% that it occurred in the Froude number 6.7, deflector angle of 25 degree and the side with 12-cm-length. Keywords:Energy Dissipation, Flip Bucket Spillway, Deflector, Physical Model منبع: [Hidden Content] دانلود: [Hidden Content] JCEU-C9-2013.pdf

Simplified analysis for estimation of the behavior of a submerged floating tunnel in waves and experimental verification Sung-il Seo a, *, Hyung-suk Mun a, 1, Jin-ho Lee a, 2, Jin-ha Kim b, 3 a New Transportation System Research Center, Korea Railroad Research Institute, 176, Cheoldo bangmulgwan-ro, Uiwang-City, Gyeonggi-Do, 16105, South Korea b Offshore Plant Research Division, KRISO [Korea Research Institute of Ships & Ocean Engineering], 171 Jangdong, Yusong, Daejeon, 305-343, South Korea a r t i c l e i n f o Article history: Received 3 December 2014 Received in revised form 2 September 2015 Accepted 3 September 2015 Available online xxx Keywords: Inertia force Morison's equation Physical model Linear wave theory Wave load Drag force Submerged floating tunnel a b s t r a c t To achieve rational design in waves for a submerged floating tunnel which has emerged as a new offshore transportation infrastructure, it's necessary to understand its hydrodynamic behavior. For simple but accurate estimation of hydrodynamic forces, a theoretical method is proposed and the tests with physical models in a wave flume were carried out for verification. Morison's equation was used to estimate wave loads composed of inertia force and drag force. Forces calculated by applying the linear wave theory to Morison's equation coincided well with those measured by the tests. The test results showed that mooring systems played a significant role in the movement of the submerged floating tunnel in waves. A pendulum model could be used to describe the motion of the submerged floating tunnel with a single vertical mooring. Based on the verified relations, a simple slack condition which causes the submerged floating tunnel to be unstable was also proposed. The simplified approach proposed by 10.1016_J.MARSTRUC.2015.09.002-Simplified-analysis-for-estimation-of-the-behavior-of-a-submerged-floating-tunnel-in-waves-and-experimental-verification.rar