复合材料高强度混凝土的试验研究桥梁英文文献和中文翻译(6)
Casual handling practices that are inconsequen-tial with steel cables can cause damage or breakageof CFRP tendons.5. In two ultimate load tests of bending-strength-criticalbeam designs, the CFRP cable behaved predictably.Both of the 12.19 m beams exhibited extensive crack-ing and large de¯ections before failure of the tendonsoccurred at load levels that correlate well with analyt-ical predictions based on 3450 MPa eective tendonstrength. An ultimate center de¯ection of over230 mm (length/53) was obtained in one four-pointbending test.6. Tension cracking of the beams during loadingoccurred at a lower than predicted load. Possibleexplanations include the following:(i) prestress losses were greater that the assumedvalues;(ii) the modulus of rupture of the high-strengthconcrete was lower than the value predicted byAASHTO equations.7. Shear stirrups made of GFRP rebar were used in thetest beams. No failure of these stirrups occurred dur-ing load testing or upon failure of the beams. The lowaxial modulus of GFRP rebar compared to steel (1/5as sti) and the lower shear strength and stiness sug-gest that design relationships used for steel shear rein-forcement may need revision for application toGFRP products.AcknowledgementsProgram funding was provided by the Ohio Board ofRegents Research Challenge Program. Tensioning gripswere obtained on loan from ISIS Canada. Beam testingwas sponsored by the US Air Force Research Labora-tory (AFRL/MLBC).
纤文增强聚合物(FRP)预应力筋和加强筋(钢筋)已经在混凝土中使用。纤文增强聚合物(FRP)预应力筋产品比传统的钢构件更轻且耐腐蚀。当前测试项目包括设计、制造和在两根为预应力FRP产品和加固的剪切高强度混凝土桥梁进行破环测试。该版权为爱思唯尔的科学有限公司所有。论文网
1、 介绍
在美国583000座桥梁中有235000座桥梁没有预应力和108000座有钢筋预应力混凝土桥梁。其中最主要的问题是钢筋的耐腐蚀问题。近年来，纤文增强聚合物预应力筋已经开发出来用于混凝土。这种材料改善钢筋的耐腐蚀和抗疲劳性。这种加强的混凝土桥梁相比于钢筋混凝土建筑在腐蚀性的环境中可以加强的它的寿命。
目前，大规模的纤文增强聚合物预应力筋和高强度钢筋混凝土桥梁设计,制造和测试。当前的项目提供一个单点评估的适用性纤文增强聚合物预应力筋现行设计方法梁和钢筋混凝土桥。