对带永久锚具的预应力芳纶纤维(AFRP)加固混凝土梁的疲劳、静载性能进行了试验研究,提出了预应力AFRP加固梁疲劳寿命的计算公式。5根梁的静载试验结果表明:预应力水平为55%~65%时,预应力AFRP加固梁的开裂、屈服比非预应力加固梁分别提高147%~165%和28%~50%,表明预应力加固能显著改善混凝土梁的抗弯性能。5根梁的疲劳试验结果表明:预应力加固能够显著提高梁的疲劳寿命,预应力与非预应力加固梁的疲劳寿命取决于纵筋应力幅值;预应力加固降低了梁中纵筋应力幅,疲劳寿命随着预应力水平的增大而提高。
Experimental research on static load and fatigue behaviors of strengthened reinforced concrete (RC) beams using prestressed aramid fiber reinforced polymer (AFRP) sheets with permanent anchor was carried out. The formulas for computing the fatigue life of the beams strengthened with prestressed AFRP sheets were put forward. Static load experimental results of five beams show that when prestress level is 55%~65%, the cracking load and yield load of RC beams strengthened with prestressed AFRP are 147%~165% and 28%~50% respectively. It is larger than that of RC beams strengthened with non prestressed AFRP. Five specimens fatigue experimental results show that AFRP sheet prestressed retrofitted RC beams have significantly effects on fatigue life and the fatigue life of the strengthened beam depends on the stress amplitude of the vertical steel bar; prestress reinforcement decreases vertical steel bar stress amplitude and the fatigue life of the retrofitted RC beam increases with the increase of the prestress level.