【摘要】 为了提高软土地基上大型沉井基础稳定性评价和安全监控的有效性,以江阴长江公路大桥北锚碇沉井基础为对象,在研究影响其稳定和安全运营主要因素的基础上,探讨了监控系统的主要结构,并从基础位移监控、基础抗滑稳定监控和地基土稳定监控3个方面建立了散索鞍水平位移监控模型、沉井前侧地基土水平向反力监控模型和基底反力监控模型.在综合现场观测数据和数值模拟结果的基础上,探讨了监控模型中原因量的主要构成及其与监控效应量之间函数关系的确定方法,并给出了江阴长江公路大桥北锚碇沉井基础主要控稳模型——散索鞍水平位移监控模型在通车运营期的具体函数表达式.研究结果表明,基础变位是软土地基上大型沉井基础的主要控稳因素,通过安全监控模型对其进行控制能为建筑物的安全运营提供保障.更多还原

【Abstract】 In order to raise the stability of evaluation and the effectiveness of safety monitoring of large caisson foundations in soft soil,the caisson foundation at the north anchorage of the Jiangyin Yangtze River Bridge was examined as an example.Based on studies on the factors influencing its stability and safe operation,the main structure of the monitoring system was discussed.Three monitoring models respectively for the horizontal displacement of cable saddles,the horizontal reaction force of the foundation soil in front of the caisson and the reaction force at the foundation bottom were established for evaluation of the following three monitoring aspects: the displacement of the foundation,the anti-sliding stability of the foundation,and the stability of the foundation soil. On the basis of the observed data and numerical simulation results,the main components of the cause quantity in the monitoring models and its relationship with the effect quantity were discussed.A specific expression during the period of traffic operation was proposed for the main monitoring model of the caisson foundation at the north anchorage of the Jiangyin Yangtze River Bridge,that is,the monitoring model for the horizontal displacement of cable saddles.The results show that the displacement of the foundation is the control factor for large caisson foundations in soft soil.The monitoring model is helpful to the safe operation of similar structures.更多还原