Abstract When construction of a shield tunnel in a central urban area encounters the pile foundation of an existing building (structure), having the shield cutter directly cut the pile foundation is the preferred option. With the Haizhu Bay superlarge-diameter shield tunnel used as an example, the cutter-pile foundation-stratum dynamic cutting simulation model is created by using the numerical simulation method, in order to intensively investigate the interaction mechanism of shield cutter cutting the pile foundation. Through sensitivity analysis of the key parameters such as cutter spacing, cutter ring penetration, cutterhead rotating speed and pile foundation position relative to cutterhead,the optimum values of the key parameters for the cutter to cut the pile foundation are obtained. As the results indicate: if the cutter spacing is excessively large or the cutter ring penetration is excessively small, the use of cutter to cut the pile foundation has better results and higher utilization rate. If the penetration increases, the scope of influence of the interaction between cutter and stratum-pile foundation model increases, which is beneficial for breaking and removing the pile foundation materials. If the penetration and cutterhead rotating speed are set improperly, the load of cutter breaking the pile foundation will increase. For the Haizhu Bay superlarge-diameter shield tunnel, the optimum cutter spacing is 80 mm, optimum penetration 45 mm and optimum cutterhead rotating speed 2 r/min.
Abstract：
When construction of a shield tunnel in a central urban area encounters the pile foundation of an existing building (structure), having the shield cutter directly cut the pile foundation is the preferred option. With the Haizhu Bay superlarge-diameter shield tunnel used as an example, the cutter-pile foundation-stratum dynamic cutting simulation model is created by using the numerical simulation method, in order to intensively investigate the interaction mechanism of shield cutter cutting the pile foundation. Through sensitivity analysis of the key parameters such as cutter spacing, cutter ring penetration, cutterhead rotating speed and pile foundation position relative to cutterhead,the optimum values of the key parameters for the cutter to cut the pile foundation are obtained. As the results indicate: if the cutter spacing is excessively large or the cutter ring penetration is excessively small, the use of cutter to cut the pile foundation has better results and higher utilization rate. If the penetration increases, the scope of influence of the interaction between cutter and stratum-pile foundation model increases, which is beneficial for breaking and removing the pile foundation materials. If the penetration and cutterhead rotating speed are set improperly, the load of cutter breaking the pile foundation will increase. For the Haizhu Bay superlarge-diameter shield tunnel, the optimum cutter spacing is 80 mm, optimum penetration 45 mm and optimum cutterhead rotating speed 2 r/min.
WANG Defu
.Study on Interaction Mechanism and Key Parameters of Shield Cutter Cutting the Pile Foundation—Case Study of Haizhu Bay Shield Tunnel Project[J] MODERN TUNNELLING TECHNOLOGY, 2024,V61(1): 216-228
2024, Vol. 61 