This paper aims to provide a new approach to predict the friction resistance of slurry pipe jacking. Friction force usually\nconstitutes the main component of jacking force. It can be calculated by multiplying an effective friction coefficient and the normal\nforce acting on the external surface of the pipe. This effective friction coefficient is introduced to reflect the effect of contact state of\npipe soil slurry, highly affected by the effect of lubrication and the interaction of pipe soil slurry. Firstly, by making some\nreasonable assumptions, the analytical formula of the effective friction coefficient is obtained, in which the critical quantity of\ncontact (contact angle or width) is calculated by using the Persson contact model. Then, the analytical formula of normal force of\ncircular pipeline is derived, which needs to determine the vertical soil pressure. To allow for a better prediction, three typical silo\nmodels are introduced and compared. Finally, a method for calculating the friction resistance of slurry pipe jacking is established.\nThe main difference from the existing method is that this method takes into full consideration the influence of lubrication, soil\nproperties (such as internal friction angle, cohesion, and void ratio), and design parameters (such as buried depth, overcut, and\npipe diameter). By using reasonable silo models, the predicted results are in good agreement with the measured values collected\nfrom 10 in situ cases, which proves that the new approach can provide accuracy prediction of friction resistance for slurry pipe\njacking with various soil conditions, and it may help for better future design and less construction costs.
Loading....