大吨位预应力锚垫板设计

随着桥梁技术的发展,大吨位锚具的应用在不断增加,巨大的预压力将通过锚具及其下面积不大的垫板传递给混凝土,引起很大的局部应力。为保证锚垫板下混凝土的局部承压强度满足承载力要求,必须设计受力合理的锚垫板。本文以四渡河特大桥方案为工程背景,利用有限元分析软件ANSYS模拟分析锚垫板在张拉预应力过程中的局部应力分布规律,以此为据改变锚垫板的结构型式,改善锚下混凝土应力分布情况,探索大吨位锚具局部承压可靠的方法。

Design of the Anchor Plate under Large Tonnage Pre-Stress

As the technique of bridge develops,the large tonnage anchorage has been used on the increase.Concrete should be sustained great pre pressure through anchorage and plate,leading to large partial pressure.In order to make the concrete under the anchor plate being strong enough to support the large partial pressure,the anchor plate should be matched.Taking the project of large bridge of Si-Du River as an example,this paper analyzes the distribution discipline of the local stress of the anchor plate pre-stressed with localized tendons by simulation with ANSYS,and explores the reliable solutions of partial pressure of large tonnage anchorage by changing the structure of anchor plate and improving the stress distribution of concrete under anchor plate.