沉井下沉过程的运动学特性与下沉控制研究

软土地层中沉井下沉影响机制复杂，现有的理论研究主要基于沉井的受力特性开展下沉分析，沉井下沉过程中的运动学特性缺乏科学系统的阐释。对沉井下沉运动过程进行分析，建立沉井下沉力学模型，推得沉井下沉过程的运动学方程，揭示了沉井下沉的运动学特性和影响机制。并结合实际工程案例验证了该方法的合理性和正确性。研究结果表明，沉井下沉具有典型的下沉加速及下沉减速阶段；沉井下沉施工引起的初始下沉不平衡力?F1是影响下沉运动特征的重要因素，也是下沉运动控制的首要因素；调整反映土层及沉井结构特征的参数b1是预防沉井突沉的有效手段。

Kinematic characteristics and sinking control of open caisson during sinking process

The influence mechanism of open caisson sinking in soft soil stratum is complex. The available theoretical research mainly focused on the mechanical characteristics of open caisson for analyzing the sinking process. The kinematic characteristics of open caisson during sinking process are lack of scientific and systematic interpretation. To this end, this paper establishes the mechanical model of open caisson sinking, deduces the kinematic equation of open caisson, and reveals the kinematic characteristics and the influence mechanism of the open caisson during sinking process. The rationality and correctness of the theoretical method is verified based on a practical project. The research results show that the sinking process of open caisson has obvious acceleration sinking stage and deceleration sinking stage. The initial unbalance force before sinking (?F1) caused by sinking construction of open caisson is an important factor affecting the sinking characteristics, as well as the primary factor for controlling the sinking movement. Adjusting the parameter b1, which reflects the characteristics of soil layer and open caisson structure, is an effective method to prevent sudden sinking of open caisson.