（1 北京市建筑工程研究院有限责任公司，北京 100039；2 北京交通大学，北京 100081）

[摘要]  结合了无粘结技术施工简便和有粘结技术安全可靠特点的缓粘结预应力技术得到了较大的关注，并开始在实际工程中获得应用。考虑到预应力技术多应用于重要基础设施，其结构事故将给人民生命和财产带来灾难性后果，因此对预应力筋的预应力状态进行监测是十分必要的。不幸的是由于传感器本身问题和布设工艺的限制，现有监测用传感器仍无法满足实际工程的需要。本文从缓粘结预应力混凝土结构和光纤传感技术的特点出发，设计制作了可实现对自身预应力状态监测的新型缓粘结智能钢绞线，并通过系列实验考察其力学和传感性能。结果表明：新型自监测缓粘结智能钢绞线具有满足实际工程长期监测需要的力学和传感性能：其极限抗拉强度大于1660MPa，约为普通钢绞线的88％；弹性模量为170GPa左右；传感测试总精度约为2.67％。

[关键字]  缓粘结钢绞线;预应力损失;监测评估;光纤传感

中图分类号：TU378          文献标识码：A          文章编号：1002-848X(2013)S1-1471-04

*国家自然科学基金（50978079）。

作者简介：兰春光，博士，博士后，Email:lcg9801121@163.com。

Development of novel self-monitoring retard-bonded smart prestressed steel strand

Lan Chunguang^1,2，Liu Hang¹

（1 Beijing Building Constitute Research Institute，Beijing 100039；2 Beijing Jiaotong University，Beijing 100081）

Abstract：Combined simplicity of unbounded prestressed technique and safety of bonded prestressed technology, the retard-bonded prestressed technology has been great concerned and used in practical engineering. Considering that retard-bonded technology usually been applied to critical infrastructure, the disastrous consequences would come from the invalidation of prestressed construction. So it is important to monitor the prestressing value of tendons. Unfortunately, there are no sensors and installation process to meet the need of practical engineering because of their disadvantages. In this paper, according to characteristics of retard-bonded prestressed concrete and optical fiber sensing, novel self-monitoring retard-bonded smart steel strand was designed and manufactured. Then the mechanical and sensing properties were studied by a series of experiments. The results show that the mechanical and sensing properties of the self-monitoring smart steel strand can fit the long-term monitoring of practical engineering, and the smart steel strand have the ultimate tensile strength of over 1660MPa (88% of common steel strand), the elastic modulus of 170GPa, and the high test precision of about 2.67%.

Keywords：retard-bonded steel strand;loss of prestress;monitoring and evaluation;optical fiber sensor