第 33 卷第 6 期 辽宁工程技术大学学报(自然科学版) 2014年 6 月
Vol.33
No.6 Journal of Liaoning Technical University(Natural Science) Jun. 2014
收稿日期:2014-01-11
作者简介:戴成元(1974-),男,内蒙古 宁城人,硕士,副教授,主要从事道路路基、边坡稳定、桥梁隧道及地下工程抗震理论应用等方面的研究.
通讯作者:赵建梅(1988-),女,辽宁 黑山人,硕士研究生,主要从事岩土工程方面的研究. 本文编校:史庆华
文章编号:1008-0562(2014)06-0810-06 doi:10.3969/j.issn.1008-0562.2014.06.019
混合预应力抗弯加固钢筋混凝土“T”梁有限元分析
戴成元
1
,赵建梅
1
,李广华
2
(1. 辽宁工程技术大学 土木与交通学院,辽宁 阜新 123000;2. 北京城建七建设工程有限公司,北京 100029)
摘 要:为了解决现役桥梁加固造价高、加固过程中易造成黏结破坏及加固材料难以完全发挥作用等问题,提出
混合预应力加固技术.结合连江大桥 16 m“T”梁段,利用 Midas CIVIL 有限元软件,对其进行结构核算和加固
前后有限元分析.结果表明:混合预应力加固技术将先张法和后张法同时作用于被加固结构构件,改变了传统加
固技术的传力机理,加固后的“T”梁,在基本不增加“T”梁自重的情况下,“T”梁的抗弯、抗剪承载力得到
明显提高,整体挠度和裂缝宽度得到有效减小,较好地解决了加固后“T”梁延性差的问题,同时采用普通水泥
砂浆替代普遍采用的高性能砂浆,降低工程造价,与现有桥梁加固技术相比具有明显优势,值得在桥梁加固工程
中推广应用.
关键词:钢筋混凝土;“T”梁;混合预应力加固;强度验算;数值模拟;先张法;后张法;应力计算
中图分类号:TU 43 文献标志码:A
Mixed prestressed fexural strengthening concrete T beam
of finite element analysis
DAI Chengyuan
1
, ZHAO Jianmei
1
, LI Guanghua
2
(
1. Liaoning Technical University, Institute of Civil Engineering and Transportation,Fuxin 123000,
China;2.Beijing Urban Construction Seven Construction engineering co., LTD, Beijing 100029,China
)
Abstract: In order to solve the high cost, bond failure and reinforcement material of active bridge strengthening,
this paper putforward a mixed prestressed reinforcement technology. Combining with LianJiang 16m T beam, this
study utilized Midas CIVIL finite element software, and performed the accounting structure and finite element
analysis of before and after reinforcement. The results show that mixed prestressed reinforcement technology
combines pre-tensioned with post-tensioned simultaneously on the reinforced structural member, which has
changed the traditional transfer mechanism of reinforcement technology. After the bridge reinforcement, in the
general case without increasing the weight of the bridge, bending and shear capacity of T beam has been
significantly improved, and overall deflection and crack width have been effectively reduced, which is a better
solution to the problem of poor ductility T beam, and reduces project cost by using ordinary cement mortar to
replace high-performance mortar. Compared with the existing bridge reinforcement technology, the method has
obvious advantages, and it is worth applying in bridge strengthening projects.
Key words: reinforced concrete; T beam; mixed prestressed reinforcement; strength calculation; the numerical
simulation; pretensioning method; post-tensioning method; stress calculation
0 引 言
现行 P-SWR 是传统思想的后张法加固,对旧
结构构件施加预应力,防护砂浆仅仅提供连接,并
且为满足长久加固的理念只能使用高性能砂浆,以
避免和减缓预应力材料的锈蚀,这样造成造价偏
高,并且容易造成黏结破坏
[1-2]
.文中提出的混合预
应力加固通过改进传力机理,结合后张法与先张法
综合传力的特点,混合利用先张法与后张法施工方
法,同时普遍采用的高性能渗透砂浆将由普通水泥
砂浆替代,在降低加固工程造价的同时对维修和保
养现役桥梁也存在明显优势.混合预应力加固技术
施工工艺流程为:端部开槽和剔除旧混凝土表面碳
化部分→压力水冲刷洗净粗糙面→钢板锚具固定
→间隔对称张拉预应力钢丝或钢绞线→张拉完成,
涂抹界面剂(水泥净浆)→预应力钢丝或钢绞线外
侧普通砂浆防护层施工→普通砂浆防护层养护到
设计强度,按照设计间隔对称放松指定预应力钢丝