Applied Mechanics and Materials Vols. 212-213

Abstract: The anti-scour velocity of revetment blocks for flood control project of Mulan Creek river was studied through flume experiments. The results show that the revetment stability is related to the surface smoothness of revetment blocks. If they are paved smoothly, the incipient velocity of the blocks is greater than 4.0m/s, otherwise it is smaller than 3.2m/s. Hence, the smooth armour layer of revetment blocks are more stable than the others. According to distributions of flow velocities during flood in the river, the armor block types for different reaches of Mulan Creek river are suggested.

Abstract: Submerged breakwaters have become increasingly popular due to their multiple functions, which are to protect shoreline or harbor and to prevent beach erosion in the coastal zones. In this paper trapezoidal submerged breakwater in the coastal zones was modeled using a wave flume. Based on the experimental data collected, characteristics of changing wave profile, energy spectrum, statistic and spectrum parameters of regular waves were calculated and analyzed. The result shows that the wave profile becomes strongly asymmetry and wave energy in lower harmonic is transferred into higher harmonic. At the back of submerged breakwater the wave energy rapidly decreases. The higher harmonics generate and intensify near the bottom or when the water depth decreases.

Abstract: The expansion effect of the MgO concrete must meet the requirement of the design for the temperature control. In this paper, its influence to the construction stress is studied using 3D FEM method. Results show that the expansion of MgO at later age is good for compensating the shrinkage induced by temperature drop and the expansion of MgO can improve the stress status in the constrained zones but may worsen the stress status in other zones. This provides the reference for popularizing dam construction technology with MgO concrete.

Abstract: The hydraulic structure visual forms are both a water project construction component, but also the important contents in the design of hydraulic structures. So that at the same time to satisfy the engineering function, given a certain culture connotation and time spirit, become the material function and mental functions complement each other forms. The article integrates design elements according to parts of Xinjiang reservoir project building design, , puts forward the according design thought and method.

Abstract: Bonding steel technique plays an important role in strengthening and eliminating dangers. As for special of hydraulic structure,application of it is not very common.This text combines Nonlinear FEM software ANSYS to Comparative analysis the static performance of the diversion tunnel on hualiangting reservoir and determine the structure scheme.

Abstract: The length of the stripping time of the diversion tunnel concrete lining of hydropower station will affect construction speed of the lining and increase the project cost. In combination with the actual situation of derivation tunnel in ASAHAN NO.1 hydropower station project, and using concrete strength test and mathematical model calculation, this article explores the proper stripping time of side and roof arch steel trolley.

Abstract: The principle of energy dissipation in stilling basin is based on hydraulic jump formation. Due to the inherent fluctuating characteristic of the hydraulic jump, basin floor is subjected to variations of pressure, resulting in unstableness due to uplift forces. To increase the efficiency of the stilling basins and improve the energy dissipation rate, one or two rows of baffle blocks are applied on the basin floor. Causing a forced hydraulic jump, tension and compression forces are exerted by pressure fluctuations of rotating roller zone of hydraulic jump. In this investigation, to observe the impacts of baffle blocks on pressure fluctuations on basin floor, a standard USBR basin model type III was constructed, and then a second row of blocks was added to the basin. A set of pressure tubes was fixed along the axis of the basin to measure the static and dynamic pressures on basin floor. The results were expressed in dimensionless parameters including C-p, C+p, C’p, Cp. Also, power spectra of pressure fluctuations were calculated. The results show a decreasing trend in root mean square of pressure fluctuations as distancing from toe of jump along the basin with and without baffle blocks. Also, mean pressure increases when water jet strokes the basin then decreases under roller zone of jump and increases again after sequent depth. The spectral analysis indicates that the dominant frequency is between 10 rad/s and 35 rad/s and pressure fluctuations have low frequency characteristics.

Abstract: According to the analysis of Nuozhadu's core rockfill dam over its relationship of material balance and progress coordination between filling and excavation engineering, by means of linear programming method, combining with the actual construction, mathematical model of earthwork allocation optimization is established. Through using the actual application, it achieves the goal of saving resources and cost, reasonable and fast construction.

Abstract: The water system of an inner lake in a planned residential district is connected to the Tuanbo reservoir. To pass through the city road between this residential district and the Tuanbo reservoir and effectively control the water table level of the inner lake, two sluices with two box-culverts will be built under the city road. In the existing design, the cross-section and the base slab of the sluices are relatively greater than what is necessary, which is on the conservative safer side but not as economical. Considering the project requirements and load characteristics, this paper proposes different design solutions for the cross section of the sluices through comparison and analysis of the stresses and foundation deformations on the sluice walls, and base slab by means of FEM and computer simulation. As a result, an optimal cross-sectional structure of the sluices was selected, which significantly reduces the use of concrete, and is much more cost efficient than the existing design.

Abstract: The stress and deformation of cut-off wall will be changed as the water level cyclical varying during reservoir's operation. Therefore, the prediction is important to the safety and stability of reservoir. In this paper, the seepage characteristics of the highest and the lowest water level condition have been predicted, and the variation of horizontal displacement is discussed under the vehicle load of road and cyclical fluid load. Meanwhile, the displacement distribution and stress state in junction area of the upper wall and the lower wall are obtained. The results show that the Cut-off wall is less affected by the vehicle load of road, and its stress and deformation will gradually stabilize after the second water store-discharge cycle. The upper reinforced concrete wall will tilt towards outside of reservoir, but the deformation is very small at lower plastic concrete wall. The guide wall has a good effect on preventing the upper wall's inclining and improving the lower wall's stress environment. Besides, the maximum principle stress of cut-off wall is too small to course plastic failure.