Experimental Research on Thin-walled Box Girder with CFRP External Prestressed Self-compacting Concrete

摘要

With the increase of bridge span, traditional prestressed concrete thin-walled box girder faced with difficult problems in structure's high self-weight, casting, steel corrosion etc. In order to solve these problems, two new materials, self-compacting concrete and CFRP, have been introduced in thin-walled box girder with CFRP external prestressed self-compacting concrete. Therefore, it colligated the self-compacting high-performance concrete good performances of high-strength durability, vibration-free, environmental protection, energy-saving etc and gave full play to high-strength carbon fiber sheets of lightweight, stainless and other good features by using external prestressed. It can also reduce the structural forces, prevent steel corrosion, improve the durability of the structure and increase the across capacity of the structure. The main researches are as follows: considering particular characteristics of the concrete thin-walled box girder, optimization research on mix proportion for self-compacting high-performance concrete, discussion on carbon fiber sheets in vitro prestressed anchoring mechanism and tension method have been conducted. A reasonable implementation plan has been proposed, and the experimental research on behavior of the thin-walled concrete box girder has been investigated after the implementation of tension. The theoretical basis and test data have been obtained in the application of the self-compacting high-performance concrete in vitro prestressed concrete and high-performance carbon fiber sheets in the thin-walled concrete box girder.