塌陷地震作用下劣化洗煤厂皮带栈桥安全性预测  

Safety Prediction of Belt Trestle in Coal Washery under the Collapse Earthquake

作　　者：丁莎 刘俊[1,2] 范力 DING Sha;LIU Jun;FAN Li(Department of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an Shaanxi 710055,China;XAUAT Engineering Technology Co.,Ltd.,Xi’an Shaanxi 710055,China)

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055 [2]西安建筑科大工程技术有限公司,陕西西安710055

出　　处：《工程质量》2022年第6期1-7,共7页Construction Quality

摘　　要：洗煤厂皮带栈桥长期处于潮湿环境,栈桥钢结构通廊以及钢筋混凝土支架均发生不同程度的腐蚀。现场调查发现:钢结构通廊0.4 m范围以下钢构件锈蚀较为严重;钢筋混凝土支架柱局部锈胀开裂。通过现场截取钢材样本,采用3D扫描技术对锈蚀钢材表面形貌进行重建,确定钢桁架梁斜腹杆、横向小桁架以及下弦杆平均锈蚀深度;而钢筋混凝土支架柱、梁箍筋和纵筋的锈蚀率则采用已有钢筋锈蚀模型进行计算;采用SAP2000软件考虑锈蚀构件截面损失对栈桥结构进行了承载力验算;最后,采用SeismoArtif软件拟合人工波模拟塌陷地震作用对劣化栈桥进行时程分析,对劣化栈桥的安全性进行了预测。结果表明,在不同荷载工况下,锈蚀栈桥结构部分杆件安全储备较低,但是在满足正常设防烈度下的承载力验算可以保证劣化栈桥在塌陷地震作用下结构不发生倒塌。The belt trestles of coal washery have been in humid environment for a long time. Steel corridor and reinforced concrete support of trestle structure have different degrees of corrosion. The field investigation shown that the corrosion of steel members was serious below 0.4m of steel corridor,and the reinforced concrete support columns was rusted and cracked. Meanwhile the surface morphology of corroded steel was reconstructed by using 3D scanning technology through intercepting steel samples on site. What’s more,the average corrosion depth of oblique web member,transverse small truss and lower chord of steel truss beam was determined. The corrosion rates of stirrups and longitudinal bars for reinforced concrete support columns and beams were calculated by the existing steel corrosion model. And then,the bearing capacity of trestle structure was checked by SAP2000 software considering the cross-section loss of corroded members. Finally,the time history analysis of the deteriorated trestle is carried out,which is using SeismoArtif software fitting artificial wave to simulate the collapse earthquake action,and the safety of the belt trestle is predicted.The results showed that the safety reserve of some members of the corroded trestle structure was low under different load conditions. However,the bearing capacity calculation under the normal fortification intensity can ensure that the deteriorated trestle will be not collapsed under the collapse earthquake.

关 键 词：塌陷地震 钢结构通廊 钢筋混凝土支架 锈蚀 承载力 

分 类 号：TU375[建筑科学—结构工程]