| This paper is part of the project supported by national natural science foundation of china, "Field and Laboratory studies on the fresh ice thermal expansion stress forming processes in reservoirs (50879008)".Cold air always pass Northeast, Central North, and Northwest territories in China and cause temperature drop. Hydraulic structures often come in for the destruction from the static ice pressure. The Hongqipao reservior is located in Heilongjiang Province, latitude high. Average temperature often is-20.5℃in January. Reservoirs freeze early, ice thickness 0.7m-1.5m. When the temperature rises, The expansion of the ice layer may cause serious damage to the slope protection. Scholars pay more attention to ice growth and ice forces on structures but less attention to physical and mechanical properties of ice in the reservoir ice. Because the action of ice layer to the slope protection is very complex, So far, the calculation on static ice pressure is still in the research stage.Because there is direct relationships on changes in ice temperature, air temperature and ice growth, ice forces, first author analyses changes of ice temperature along the ice thickness and growth rate of ice. Second we establish the numerical relationship of ice temperature and air temperature, analyse the impact of the temperature to the ice thickness. We establish the relationship on the ice thickness and the simple model of ice growth. Final author ascertain the relationship of static ice pressure and uniaxial compressive strength, calculate the static ice pressure value of different ice layer. For providing a theoretical basis to solve practical problems in engineering, We discuss the results of the laboratory test and the formula used. Author observes the ice-breaking groove in the Hongqipao reservior, and illustrates that the ice-breaking groove can weaken the action of the ice layer on the slope protection. In addition, We observe the damage of the dam ancillary facilities and ice accumulation.
|
PDF Full Text Request