Permeation grouting is widely applied for its low grouting pressure and minor disturbance to the stratum in grouting engineering, especially in engineering with strict requirements on ground settlement. However, perme...Permeation grouting is widely applied for its low grouting pressure and minor disturbance to the stratum in grouting engineering, especially in engineering with strict requirements on ground settlement. However, permeation grouting theory lags behind compared with other engineering disciplines, and the theoretical formulas now available cannot accurately be used to guide grouting engineering design and predict the cost and effects of grouting due to many factors affecting grout permeation in stratum. In this study, permeation grouting experiment devices were independently manufactured with the characteristics of easily controlling grouting pressure, simulating sandy strata grout, and detecting grouting effect. Using a uniform design, the sand consolidation agent, as grouting material, its spread in Shenyang sandy strata was tested with these experiment devices. The quantitative relations between grouting factors (grouting pressure, strata parameters, water-sand consolidation agent ratio) and grouting effects (grout spread radius, gell strength, grout amount) are obtained with regression analysis, and the influence degree of grouting factors on grouting effects is studied.展开更多
The contact angle is one of important parameters to simulate droplet spreading and impingement phenomena on the surface. In the most numerical research, it is assumed constant value and it is implemented as boundary c...The contact angle is one of important parameters to simulate droplet spreading and impingement phenomena on the surface. In the most numerical research, it is assumed constant value and it is implemented as boundary condition. However, contact angle is changed according to contact line velocity and time. Hence, for accurate simulation, dynamic contact angle which has various values as time elapsed is adopted. In the present study, the numerical analysis is performed on the droplet spreading phenomena considering dynamic contact angle function which is obtained from single droplet spreading experiment on the flat and bare surface. The CIP (cubic interpolated pseudo-particle) method by Yabe is used for analysis of interface between liquid and gas phases. The numerical results considering contact angle function which newly modeled as time and contact angle are compared with numerical results considering Hoffman's function and experimental data for range of Weber number which are 4.427 and 11.334. In contrast of numerical result considering Hoffman's function, the numerical result shows good agreement with experimental data as time elapsed in contact angle evolution, deformation of droplet spreading radius and height. Indeed, overall, the results display the increasing maximum spreading radius and the decreasing height as Weber numbers increased.展开更多
基金Supported by the National Science and Technology Support Plan of 12th Five-year Plan (2012BAK24B00, 2012BAK24B0104) the National Natural Science Foundation of China (51204029) the Fundamental Research Funds of Chinese Ministry of Education (N110301003)
文摘Permeation grouting is widely applied for its low grouting pressure and minor disturbance to the stratum in grouting engineering, especially in engineering with strict requirements on ground settlement. However, permeation grouting theory lags behind compared with other engineering disciplines, and the theoretical formulas now available cannot accurately be used to guide grouting engineering design and predict the cost and effects of grouting due to many factors affecting grout permeation in stratum. In this study, permeation grouting experiment devices were independently manufactured with the characteristics of easily controlling grouting pressure, simulating sandy strata grout, and detecting grouting effect. Using a uniform design, the sand consolidation agent, as grouting material, its spread in Shenyang sandy strata was tested with these experiment devices. The quantitative relations between grouting factors (grouting pressure, strata parameters, water-sand consolidation agent ratio) and grouting effects (grout spread radius, gell strength, grout amount) are obtained with regression analysis, and the influence degree of grouting factors on grouting effects is studied.
文摘The contact angle is one of important parameters to simulate droplet spreading and impingement phenomena on the surface. In the most numerical research, it is assumed constant value and it is implemented as boundary condition. However, contact angle is changed according to contact line velocity and time. Hence, for accurate simulation, dynamic contact angle which has various values as time elapsed is adopted. In the present study, the numerical analysis is performed on the droplet spreading phenomena considering dynamic contact angle function which is obtained from single droplet spreading experiment on the flat and bare surface. The CIP (cubic interpolated pseudo-particle) method by Yabe is used for analysis of interface between liquid and gas phases. The numerical results considering contact angle function which newly modeled as time and contact angle are compared with numerical results considering Hoffman's function and experimental data for range of Weber number which are 4.427 and 11.334. In contrast of numerical result considering Hoffman's function, the numerical result shows good agreement with experimental data as time elapsed in contact angle evolution, deformation of droplet spreading radius and height. Indeed, overall, the results display the increasing maximum spreading radius and the decreasing height as Weber numbers increased.