纤维增强复合材料加固裂纹黏弹性梁的弯曲变形

doi:10.12066/j.issn.1007-2861.1869

摘要/Abstract

摘要：

考虑裂纹缝隙效应, 将裂纹等效为非线性旋转弹簧, 假定纤维增强复合材料(fiber reinforced polymer, FRP)布与梁紧密粘贴, 研究了 FRP 布加固裂纹标准线性固体黏弹性梁的弯曲行为. 在给出 FRP 布加固裂纹的等效旋转弹簧刚度和FRP布加固黏弹性矩形截面梁弯曲变形控制方程的基础上, 利用 Laplace 变换及其逆变换以及梁弯曲边界条件和裂纹处的连接条件, 得到突加均布载荷作用下 FRP 布加固简支裂纹黏弹性梁弯曲蠕变的解析解. 数值分析了碳纤维增强复合材料(carbon fiber reinforced polymer, CFRP)布含量、梁跨高比以及裂纹位置及其开闭状态等对CFRP布加固裂纹花旗松(Douglas-fir, DF)木梁弯曲蠕变的影响.

关键词: 裂纹梁, 裂纹缝隙, 纤维增强复合材料加固, 黏弹性, 解析解, 参数研究

Abstract:

Considering effect of crack gap and regarding crack as a nonlinear rotational spring, and assuming tight bonding between the fiber reinforced polymer (FRP) sheet and timber beam surface, bending performance of the cracked standard linear solid viscoelastic beam reinforced with FRP sheet was investigated. Equivalent flexural rigidity of FRP sheet-reinforced crack and the governing equation for bending deformation of viscoelastic rectangular cross-section beam reinforced with FRP sheet are presented. An analytical solution of bending creep of a simply-supported FRP sheet-reinforced cracked viscoelastic beam subject to a step uniform load was obtained with the boundary conditions and crack's continuity conditions of beam bending by using the Laplace transform and its inverse transform. The influences of volume fraction of carbon fiber reinforced polymer (CFRP) sheet, span-depth ratio of the beam, location and open-closed state of the crack on the bending creep of the CFRP sheet-reinforced cracked viscoelastic Douglas-fir (DF) timber beam were analyzed numerically.

Key words: cracked beam, crack gap, fiber reinforced polymer reinforcement, viscoelasticity, analytical solution, parameter study

中图分类号:

杨骁, 成博炜, 蒋志云. 纤维增强复合材料加固裂纹黏弹性梁的弯曲变形[J]. 上海大学学报(自然科学版), 2018, 24(6): 978-992.

YANG Xiao, CHENG Bowei, JIANG Zhiyun. Bending deformation of viscoelastic cracked beam reinforced with fiber reinforcement polymer[J]. Journal of Shanghai University（Natural Science Edition）, 2018, 24(6): 978-992.

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