玄武岩纤维与碳纤维加固连续梁抗弯试验研究

Experimental Study on Flexural Performances of Continuous Beams Strengthened with BFRP and CFRP

为分析玄武岩纤维布与碳纤维布加固混凝土T形截面连续梁的抗弯性能和破坏模式,对7根由两种纤维加固的T形截面连续梁和1根对比梁进行了抗弯试验.试验设计考虑了混凝土连续梁负弯矩区纤维布绕过柱粘贴的情况.试验结果表明,同等工况下,玄武岩纤维布对连续梁的抗弯承载力提高程度较小,但玄武岩纤维布加固梁具有更好的延性.建议国产玄武岩纤维布加固混凝土受弯构件的允许拉应变,对于重要构件不超过0.007,对于一般构件不超过0.01.实际工程中,对混凝土受弯构件加固后的承载力提高幅度要求不高且要求较好延性、耐腐蚀性的情况下,可采用玄武岩纤维复合材料.

To analyze mechanical performance and failure modes of continuous beams strengthened with basalt fiber reinforced polymer （BFRP） and carbon fiber reinforced polymer （CFRP）, flexural tests were conducted on one comparative continuous beam and seven reinforced concrete （RC） continuous beams strengthened with the two types of fibers. The method of externally bonding fiber sheets on slab along sides of column to avoid column in hogging moment area of beam was applied. The results show that bearing capacity of beams strengthened with BFRP is less than beams strengthened with CFRP, except for ductility on the same condition. Allowable tensile strain of domestic BFRP is proposed as a fixed value of O. 007 for genera! flexura! members, O. O1 for important flexural members. BFRP is a suitable strengthening material for flexural members demanding comparatively low improvement of bearing capacity, better ductility and corrosion resistance in rehabilitation and retrofit projects.