Fatigue assessment of joints in concrete-filled rectangular hollow section composite truss bridges based on hot spot stress method
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摘要: 为准确评估矩形钢管混凝土组合桁梁桥节点疲劳性能, 引入热点应力法, 可通过平面杆系模型、空间杆系模型和三维实体模型计算节点焊趾处的热点应力幅, 并通过对52个节点疲劳试验数据回归分析, 拟合得到热点应力幅-循环次数曲线; 选取陕西黄延高速一座矩形钢管混凝土组合桁梁桥为典型案例进行节点疲劳评估, 并对原有节点设计方案的构造进行优化。研究结果表明: 相比于墩顶矩形钢管混凝土节点, 跨中矩形钢管节点热点应力幅更大, 为60.1 MPa, 发生在主管表面, 但是小于欧洲规范Eurcode中的容许疲劳强度71 MPa, 满足疲劳设计要求; 对跨中疲劳易损节点进行设计构造优化, 原设计矩形钢管节点变为矩形钢管混凝土节点后, 管内混凝土改变了节点局部刚度, 使相贯线焊趾处应力分布均匀, 支、主管表面热点应力幅平均降低25.1%, 对原设计节点进行焊缝后处理, 可有效消除焊接初始拉应力, 改善节点疲劳性能, 支、主管表面热点应力幅平均降低14.9%;采用空间杆系模型对优化后的跨中矩形钢管混凝土节点进行疲劳评估, 支、主管表面最大热点应力幅分别为58.9、54.1 MPa, 大于三维实体模型计算得到的支管和主管表面最大热点应力幅45.2、47.1 MPa, 空间杆系模型计算结果偏保守, 且无法像三维实体模型一样准确计算不同热点位置的疲劳效应, 也无法准确判断疲劳开裂起始位置。Abstract: In order to accurately assess the fatigue behaviour of joints in concrete-filled rectangular hollow section steel tubular composite truss bridges, the hot spot stress method was introduced. The hot spot stress range at the weld toe can be determined by the planar frame model, spatial frame model, and three-dimensional solid model. Based on 52 fatigue test data of joints, the hot spot stress range-cycle number curves were obtained through the regression analysis. A concrete-filled rectangular hollow section steel tubular composite truss bridge located at the Huangyan highway was selected as the typical case, the fatigue behaviour of the joint was assessed, and original design details were optimized. Research results show that compared with the concrete-filled rectangular hollow section steel tubular joint on the top of the pier, the hot spot stress range in the rectangular hollow section joint at mid-span is higher, which equals to 60.1 MPa, and occurs on the main surface of the chord. However, it is less than the allowable value of 71 MPa determined according to Eurcode, thereby the design of the joints met the requirements. The optimization of design details on the fatigue vulnerable joint at mid-span is carried out. After filling the hollow section with concrete, the local joint stiffness changed, resulting in a more uniform stress distribution at the weld toe intersection. The hot spot stress ranges of brace and chord surface decrease by 25.1% on average. The post-weld treatment of the original designed joint can effectively eliminate the initial tensile stress of the welding and improve the fatigue performance of the joint. The hot spot stress ranges in the brace and chord surface decreased by 14.9% on average. Using spatial frame model to assess the fatigue behaviour of optimized joint at mid-span, the maximum hot spot stress ranges on the brace and chord are 58.9 and 54.1 MPa, respectively, both less than the results of 45.2 and 47.1 MPa calculated by using the three-dimensional solid model. It demonstrats that the result obtained by using the spatial frame model is more conservative, and the fatigue effects of different hot spots can not be calculated as accurately as the three-dimensional solid model, nor can the initial position of fatigue cracking be judged accurately.
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图 3 基于热点应力幅的Sh-N曲线(t=16 mm)
Figure 3. Sh-N curve based on hot spot stress range (t=16 mm)
图 4 矩形钢管混凝土组合桁梁桥
Figure 4. Concrete-filled rectangular hollow section composite truss bridge
图 9 矩形钢管混凝土节点三维实体模型
Figure 9. Three-dimensional solid model of concrete-filled rectangular hollow section joint
图 13 跨中和墩顶节点热点应力幅分布
Figure 13. Hot spot stress range distributions of joints at midspan and on the pier top
图 14 跨中矩形钢管节点和矩形钢管混凝土节点热点应力幅分布
Figure 14. Hot spot stress range distributions of rectangular hollow section joint and concrete-filled rectangular hollow section joint at midspan
图 15 跨中节点焊缝未处理和焊缝处理后的热点应力幅分布
Figure 15. Hot spot stress range distributions of joints at midspan without and with post-weld treatment
图 18 节点内力基本荷载工况组合
Figure 18. Combinations of internal force basic load conditions of joint
表 1 矩形钢管节点考虑次弯矩的杆件轴力放大系数
Table 1. Magnification factors of member axial forces considering secondary bending moments for rectangular hollow section joints
节点类型 节点形式 弦杆 竖腹杆 斜腹杆 间隙节点 K型 1.5 - 1.5 N型 2.2 1.6 搭接节点 K型 - 1.3 N型 2.0 1.4 
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表 2 节点应力集中系数最大值计算公式
Table 2. Formulae of maximum stress concentration factors for joints
位置 应力集中系数公式 
荷载工况1:支管拉压平衡荷载 主管 smax=(0.437+0.121β+0.046β2)·γ0.626τ0.311(g′)-0.000 05[sin(θ)]0.793 支管 smax=(0.529+0.646β+0.131β2)·γ0.509τ0.162(g′)-0.000 05[sin(θ)]0.420 荷载工况2:主管轴力 主管 smax=(1.170+0.116β-0.341β2)·γ0.139τ-0.692(g′)-0.006[sin(θ)]0.194 支管 smax=0 荷载工况3:主管弯矩 主管 smax=(2.048+0.495β-0.852β2)·γ0.047τ-0.537(g′)-0.003[sin(θ)]-0.068 支管 smax=0 适用范围 0.35≤β≤1.00, 10≤γ≤35, 0.25≤τ≤1.00, 30°≤θ≤60°, 2τ≤g′
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[1] 刘彬, 刘永健, 周绪红, 等. 中等跨径装配式矩形钢管混凝土组合桁梁桥设计[J]. 交通运输工程学报, 2017, 17(4): 20-31. doi: 10.3969/j.issn.1671-1637.2017.04.003LIU Bin, LIU Yong-jian, ZHOU Xu-hong, et al. Design of mid-span fabricated RCFST composite truss bridge[J]. Journal of Traffic and Transportation Engineering, 2017, 17(4): 20-31. (in Chinese). doi: 10.3969/j.issn.1671-1637.2017.04.003 [2] 刘永健, 马印平, 田智娟, 等. 矩形钢管混凝土组合桁梁连续刚构桥实桥试验[J]. 中国公路学报, 2018, 31(5): 53-62. doi: 10.3969/j.issn.1001-7372.2018.05.007LIU Yong-jian, MA Yin-ping, TIAN Zhi-juan, et al. Field test of rectangular concrete filled steel tubular composite truss bridge with continuous rigid system[J]. China Journal of Highway and Transport, 2018, 31(5): 53-62. (in Chinese). doi: 10.3969/j.issn.1001-7372.2018.05.007 [3] 高诣民, 刘永健, 周绪红, 等. 高性能钢管混凝土组合桁梁桥[J]. 中国公路学报, 2018, 31(12): 174-187. doi: 10.3969/j.issn.1001-7372.2018.12.017GAO Yi-min, LIU Yong-jian, ZHOU Xu-hong, et al. High-performance CFST composite truss bridge[J]. China Journal of Highway and Transport, 2018, 31(12): 174-187. (in Chinese). doi: 10.3969/j.issn.1001-7372.2018.12.017 [4] TIAN Zhi-juan, LIU Yong-jian, JIANG Lei, et al. A review on application of composite truss bridges composed of hollow structural section members[J]. Journal of Traffic and Transportation Engineering (English Edition), 2019, 6(1): 94-108. doi: 10.1016/j.jtte.2018.12.001 [5] 周绪红, 刘永健, 姜磊, 等. PBL加劲型矩形钢管混凝土力学性能研究综述[J]. 中国公路学报, 2017, 30(11): 45-62. doi: 10.3969/j.issn.1001-7372.2017.11.006ZHOU Xu-hong, LIU Yong-jian, JIANG Lei, et al. Review on mechanical behavior research of concrete filled rectangular hollow section tube stiffened with PBL[J]. China Journal of Highway and Transport, 2017, 30(11): 45-62. (in Chinese). doi: 10.3969/j.issn.1001-7372.2017.11.006 [6] 周建庭, 郑丹. 保障我国桥梁安全的战略思考[J]. 中国工程科学, 2017, 19(6): 27-37. https://www.cnki.com.cn/Article/CJFDTOTAL-GCKX201706006.htmZHOU Jian-ting, ZHENG Dan. Safety of highway bridges in China[J]. Strategic Study of CAE, 2017, 19(6): 27-37. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-GCKX201706006.htm [7] 姜磊, 刘永健, 王康宁. 焊接管节点结构形式发展及疲劳性能对比[J]. 建筑结构学报, 2019, 40(3): 180-191. https://www.cnki.com.cn/Article/CJFDTOTAL-JZJB201903019.htmJIANG Lei, LIU Yong-jian, WANG Kang-ning. Development of welded tubular joints and comparison of fatigue behaviour[J]. Journal of Building Structures, 2019, 40(3): 180-191. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-JZJB201903019.htm [8] 刘永健, 姜磊, 王康宁. 焊接管节点疲劳研究综述[J]. 建筑科学与工程学报, 2017, 34(5): 1-20. doi: 10.3969/j.issn.1673-2049.2017.05.002LIU Yong-jian, JIANG Lei, WANG Kang-ning. Review of fatigue behavior in welded tubular joints[J]. Journal of Architecture and Civil Engineering, 2017, 34(5): 1-20. (in Chinese). doi: 10.3969/j.issn.1673-2049.2017.05.002 [9] LIU Jiang, LIU Yong-jian, ZHANG Chen-yu, et al. Temperature action and effect of concrete-filled steel tubular bridges: a review[J]. Journal of Traffic and Transportation Engineering (English Edition), 2020, 7(2): 174-191. doi: 10.1016/j.jtte.2020.03.001 [10] WEI Xing, WEN Zong-yi, XIAO Lin, et al. Review of fatigue assessment approaches for tubular joints in CFST trusses[J]. International Journal of Fatigue, 2018, 113: 43-53. doi: 10.1016/j.ijfatigue.2018.04.007 [11] VAN WINGERDE A M, PACKER J A, WARDENIER J. Criteria for the fatigue assessment of hollow structural section connections[J]. Journal of Constructional Steel Research, 1995, 35(1): 71-115. doi: 10.1016/0143-974X(94)00030-I [12] DEHGHANI A, ASLANI F. Fatigue performance and design of concrete-filled steel tubular joints: a critical review[J]. Journal of Constructional Steel Research, 2019, 162: 105749-1-17. [13] LAN X Y, CHAN T M. Recent research advances of high strength steel welded hollow section joints[J]. Structures, 2019, 17: 58-65. doi: 10.1016/j.istruc.2018.11.015 [14] ZHAO X L, TONG L W. New development in steel tubular joints[J]. Advances in Structural Engineering, 2011, 14(4): 699-715. doi: 10.1260/1369-4332.14.4.699 [15] 姜磊. 矩形钢管混凝土梁桥节点疲劳性能和计算方法研究[D]. 西安: 长安大学, 2019.JIANG Lei. Research on fatigue behaviour and calculation method of joints in concrete-filled rectangular hollow section truss bridge[D]. Xi'an: Chang'an University, 2019. (in Chinese). [16] JIANG Lei, LIU Yong-jian, FAM A. Stress concentration factors in joints of square hollow section (SHS) brace and concrete-filled SHS chord under axial tension in brace[J]. Thin-Walled Structures, 2018, 132: 79-92. doi: 10.1016/j.tws.2018.08.014 [17] JIANG Lei, LIU Yong-jian, FAM A. Stress concentration factors in concrete-filled square hollow section joints with perfobond ribs[J]. Engineering Structures, 2019, 181: 165-180. doi: 10.1016/j.engstruct.2018.12.016 [18] JIANG Lei, LIU Yong-jian, FAM A, et al. Fatigue behaviour of non-integral Y-joint of concrete-filled rectangular hollow section continuous chord stiffened with perfobond ribs[J]. Engineering Structures, 2019, 191: 611-624. doi: 10.1016/j.engstruct.2019.04.089 [19] JIANG Lei, LIU Yong-jian, FAM A, et al. Stress concentration factor parametric formulae for concrete-filled rectangular hollow section K-joints with perfobond ribs[J]. Journal of Constructional Steel Research, 2019, 160: 579-597. doi: 10.1016/j.jcsr.2019.06.005 [20] JIANG Lei, LIU Yong-jian, FAM A, et al. Fatigue behavior of integral built-up box Y-joints between concrete-filled chords with perfobond ribs and hollow braces[J]. Journal of Structural Engineering, 2020, 146(3): 04019218-1-15. [21] 刘永健, 姜磊, 熊治华, 等. PBL加劲型矩形钢管混凝土受拉节点热点应力集中系数计算方法[J]. 交通运输工程学报, 2017, 17(5): 1-15. doi: 10.3969/j.issn.1671-1637.2017.05.001LIU Yong-jian, JIANG Lei, XIONG Zhi-hua, et al. Hot spot SCF computation method of concrete-filled and PBL-stiffened rectangular hollow section joint subjected to axial tensions[J]. Journal of Traffic and Transportation Engineering, 2017, 17(5): 1-15. (in Chinese). doi: 10.3969/j.issn.1671-1637.2017.05.001 [22] MASHIRI F R, ZHAO Xiao-ling. Square hollow section (SHS) T-joints with concrete-filled chords subjected to in-plane fatigue loading in the brace[J]. Thin-Walled Structures, 2010, 48(2): 150-158. doi: 10.1016/j.tws.2009.07.010 [23] MASHIRI F R, ZHAO Xiao-ling, GRUNDY P. Fatigue tests and design of welded T connections in thin cold-formed square hollow sections under in-plane bending[J]. Journal of Structural Engineering, 2002, 128: 1413-1422. doi: 10.1061/(ASCE)0733-9445(2002)128:11(1413) [24] MATTI F N, MASHIRI F R. Design formulae for predicting the stress concentration factors of concrete-filled T-joints under out-of-plane bending[J]. Structures, 2020, 28: 2073-2095. doi: 10.1016/j.istruc.2020.10.032 [25] MATTI F N, MASHIRI F R. Experimental and numerical studies on SCFs of SHS T-joints subjected to static out-of-plane bending[J]. Thin-Walled Structures, 2020, 146: 106453-1-18. [26] CHIEW S P, ZHAO M S, LEE C K. Fatigue performance of high strength steel built-up box T-joints[J]. Journal of Constructional Steel Research, 2015, 106: 296-310. doi: 10.1016/j.jcsr.2014.12.018 [27] JIANG J, LEE C K, CHIEW S P. Residual stress and stress concentration effect of high strength steel built-up box T-joints[J]. Journal of Constructional Steel Research, 2015, 105: 164-173. doi: 10.1016/j.jcsr.2014.11.008 [28] MASHAYEKHI M, SANTINI-BELL E. Fatigue assessment of a complex welded steel bridge connection utilizing a three-dimensional multi-scale finite element model and hotspot stress method[J]. Engineering Structures, 2020, 214: 110624-1-12. [29] LIU Z, CORREIA J, CARVALHO H, et al. Global-local fatigue assessment of an ancient riveted metallic bridge based on submodelling of the critical detail[J]. Fatigue and Fracture of Engineering Materials and Structures, 2019, 42: 546-560. doi: 10.1111/ffe.12930 [30] COSTA BORGES L A. Size effects in the fatigue behaviour of tubular bridge joints[D]. Coimbra: University of Coimbra, 2008. [31] VAN WINGERDE A M. The fatigue behaviour of T- and X-joint made of square hollow sections[J]. Heron, 1992, 37(2): 1-182. [32] WANG Ke, TONG Le-wei, ZHU Jun, et al. Fatigue behavior of welded T-joints with a CHS brace and CFCHS chord under axial loading in the brace[J]. Journal of Bridge Engineering, 2013, 18(2): 142-152. doi: 10.1061/(ASCE)BE.1943-5592.0000331 [33] TONG L W, XU G W, YANG D L, et al. Fatigue behavior and design of welded tubular T-joints with CHS brace and concrete-filled chord[J]. Thin-Walled Structures, 2017, 120: 180-190. doi: 10.1016/j.tws.2017.08.024 [34] 马印平, 刘永健, 刘江. 基于响应面法的钢管混凝土组合桁梁桥多尺度有限元模型修正[J]. 中国公路学报, 2019, 32(11): 51-61. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL201911005.htmMA Yin-ping, LIU Yong-jian, LIU Jiang. Multi-scale finite element model updating of CFST composite truss bridge based on response surface method[J]. China Journal of Highway and Transport, 2019, 32(11): 51-61. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL201911005.htm [35] 刘永健, 龙辛, 姜磊, 等. 基于热点应力法的钢管混凝土焊接节点疲劳构造细节比较[J]. 建筑科学与工程学报, 2020, 37(5): 1-12. https://www.cnki.com.cn/Article/CJFDTOTAL-XBJG202005002.htmLIU Yong-jian, LONG Xin, JIANG Lei, et al. Comparison on fatigue structural details of CFST welded joints based on hot spot stress method[J]. Journal of Architecture and Civil Engineering, 2020, 37(5): 1-12. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-XBJG202005002.htm -
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