软基高填土路基桥台墩柱倾斜病害及处置方法研究  

Study on Abutment Pier Inclination Disease and Treatment Method of High Filled Subgrade on Soft Foundation

作　　者：汪永林 唐忠林 吴星锌 赵靖杰 宋春霞[2] WANG Yong-lin;TANG Zhong-lin;WU Xing-xin;ZHAO Jing-jie;SONG Chun-xia(Yunnan Wuding-Yimen Expressway Co.,Ltd.,Chuxiong Yunnan 675000,China;Research Institute of Highway,Ministry of Transport,Beijing 100088,China)

机构地区：[1]云南武易高速公路有限公司,云南楚雄675000 [2]交通运输部公路科学研究院,北京100088

出　　处：《公路交通科技》2022年第10期91-98,共8页Journal of Highway and Transportation Research and Development

基　　金：中央级公益性科研院所基本科研业务费项目(2021-9072a,2021-9073a)。

摘　　要：云南某高速公路匝道桥位于软基之上,施工过程中台后路基填筑造成桥台前倾,墩柱发生倾斜,桥台和墩柱上支产生大位移滑动。为了准确分析病害产生原因和桩基病害程度并提出合理的处置措施,首先对该桥桥台变位、桥面沉降和桥台附近土体深层水平位移进行了为期1年的监测,通过对监测结果进行分析可知,墩柱变位趋于稳定,桥面未发生明显沉降,但桥台后软基层土体侧向蠕变仍在缓慢增加。为了对该桥桩基病害程度进行有效评估及为后续加固处置提供依据,对该桥下部结构及基础进行了有限元分析,建立了桩土及墩柱模型,逐工况模拟了建桥过程、台后填土作用及成桥后受力情况,全面分析了该桥现有状态下应力及变形状态。通过墩台顶实测及计算变位值对比,验证了计算模型和合理性。通过分析结果可知,在既有病害情况下,桥台及墩柱桩基应力超限,桩身开裂风险较大。鉴于此,对该桥进行了桥台搭板打孔注浆,台后下沉严重区注浆并设置抗滑桩,上设混凝土板,台背处安装限位装置等措施,以降低台后填土对桥台的作用力,防止病害进一步发展。由于软土地基中路基填筑造成的桥梁墩台病害较多,应对软土中路基与桥梁结合地带进行合理的设计,填土施工进行规范,降低软土区太厚填土对桥台及墩柱的不利影响。The ramp bridge of an expressway in Yunnan Province is located on the soft foundation. During the construction process, the embankment behind the abutment caused the abutment to tilt forward, the pier column tilted, and the upper support of the abutment and pier column produced large displacement sliding. To accurately analyze the cause of disease and the degree of pile foundation disease and put forward reasonable treatment measures, first, the displacement of the abutment, the settlement of the bridge deck and the deep horizontal displacement of the soil near the abutment are monitored for 1 year. The analysis of monitoring result shows that the pier displacement tends to be stable, there is no obvious settlement of the bridge deck, but the lateral creep of the soft base soil behind the abutment is still slowly increasing. In order to effectively evaluate the disease degree of the pile foundation of the bridge and provide the basis for the subsequent reinforcement treatment, the finite element analysis on the substructure and foundation of the bridge is carried out, the pile-soil and pier column models are established, the bridge construction process, the filling effect behind the abutment and the stress situation after the bridge completion are simulated in each working condition, and the stress and deformation state of the bridge under the existing state are comprehensively analyzed. The analysis result shows that, the stress of abutment and pier pile foundation exceeds the limit under the condition of existing diseases, and the risk of pile body cracking is large. In view of this, the measures such as drilling and grouting on abutment approach slab, grouting in the area with serious settlement behind the abutment, setting anti slide piles, setting concrete slabs on the abutment, and installing limit devices at the abutment back are taken to reduce the force of fill behind the abutment on the abutment and prevent further development of the disease. As the subgrade filling in the soft soil foundation caused ma

关 键 词：桥梁工程 桥台前倾 有限元分析 软土 加固措施 

分 类 号：U443.15[建筑科学—桥梁与隧道工程]