【摘要】 为避免悬索桥重力式锚碇混凝土结构开裂,验证锚碇结构的安全及耐久性,以矮寨大桥为背景,采用通用有限元程序ANSYS建立该桥重力式锚碇结构有限元模型,分析锚碇结构的主拉应力和主压应力。结果表明,锚碇的绝大部分区域应力均能满足要求,但在前、后锚面局部范围内存在主拉应力超标现象,且主拉应力超过了混凝土的设计抗拉强度。根据应力分析,提出在锚碇前、后锚面附近各2m范围内的混凝土采用聚丙烯纤维混凝土提高混凝土抗拉强度或者布设防裂钢筋网防止锚面开裂的建议。该桥实际采用增布钢筋网方案,在锚碇施工及通车后对前、后锚面进行了跟踪检查,均未发现明显裂缝,该方案实用效果良好。更多还原

【Abstract】 To avoid the cracking in the concrete structure of the gravity anchorage of suspen- sion bridge and to check the structural safety and durability of the anchorage,the gravity anchor- age of the Aizhai Bridge was taken as an example,the finite element model for the anchorage of the bridge was set up by the universal program ANSYS and the principal tensile stress and princi- pal compressive stress of the anchorage were analyzed.The results of the analysis indicated that the stress in the most areas of the anchorage of the bridge could satisfy the requirements.Howev- er,the phenomena of excessive principal tensile stress in the local ranges of the front and back faces of the anchorage exited and the principal tensile stress even exceeded the designed tensile strength of the concrete.In terms of the analysis,it was proposed that for the concrete structures of each 2-m range in the vicinity of the front and back faces of the anchorage,the polypropylene fiber concrete should be used to improve the tensile strength of the concrete structures or the anti- cracking reinforcement meshes should be laid to prevent the anchorage faces from cracking.For the anchorage of the bridge,the reinforcement mesh scheme was actually utilized.After the con- struction of the anchorage was completed and the bridge was open to traffic,the front and back face conditions of the anchorage were traced and inspected,no evident cracking was found in the anchorage faces and the effect of utilization of the scheme was sound.更多还原