桥梁体外预应力加固设计方法的评价分析
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摘要
体外预应力技术具有施工简单、结构可靠、造价经济等优点,在新建的桥梁结构中得到广泛的应用;同时,大量的在役桥梁,由于钢筋锈蚀以及超载等因素的影响,结构产生裂缝或变形过大,或者由于公路桥梁荷载提级的要求需要进行加固,采用体外预应力加固则是十分有效的方法之一。
本文根据现有的体外预应力混凝土试验梁数据,在理论分析的基础上对既有的多组体外预应力筋极限应力简化计算公式进行验证分析。讨论了非预应力筋配筋率、体外预应力筋配筋率、跨高比、混凝土强度、以及加载方式等对体外预应力筋极限应力增量的影响,分析了转向块、预应力束形状以及荷载形式等因素对体外预应力筋二次效应的影响。通过对比分析找出一组与试验结果吻合最好的极限应力计算公式。在此基础上再考虑现行桥梁结构设计的安全系数,即可用以指导桥梁体外预应力结构的工程设计。
通过对体外预应力加固体系受力特点的分析,评价了加固体系正截面抗弯承载力、斜截面抗剪承载力、使用状态下的体外预应力筋应力增量、使用状态下应力变形以及转向块等的计算方法,并分别通过钢筋混凝土梁和预应力混凝土梁的加固算例进行验算。从验算结果来看,本文推荐的体外预应力加固计算方法,较理想的反映了梁体在采用体外预应力加固后的受力情况,可以应用到实际桥梁工程的加固设计。
本文的计算示例均为以承载力加固为目的,也可以采用体外预应力的加固方法对结构的使用功能和耐久性进行加固。
Because of the advantages of simple construction, structural safety and economy, the external prestressing technique has been widely used in the new construction of bridges. Also, Many bridges at service are suffering from crack or over distortion due to corrosion of reinforcement bar and overweight. It is very effective to strengthen these structures using the externally prestressing technique.
According to the present experiment beam of external prestressing.This article mainly analysis the different simplified formula to the ultimate stress of external prestressing tendon on the base of theoretical analysis. Influence of various parameters including ratio of unprestressed reinforcement, ratio of external prestressing tendon, span-depth ratio, compressive strength of concrete, and loading pattern on the ultimate stress in tendon, fps, are investigated in detail. Parameters having important influence on second-order effects of externally prestressed concrete beams as deviators, tendon configuration and load type are evaluated. Then it can find almost suitable calculated formula of the ultimate stress.In this foundation, then reconsiders the safety coefficient to the bridge design.So it can be used to instruct the design of externally prestressed beam.
Through analyse the pressed characters of reforced system within external prestressing,It evaluated the calculational method of normal cross section flexural bearing capacity and normal cross section flexural bearing capacity within reinforced system.Also,it evaluated the calculational method of stress increment of external prestressing tendons,stress deformation and deviator are used.Moreover,It put up separated computations by reinforced examples of RC beams and PC beams.according from the result of checked calculation, reinforce computational method of vitro pre-stressed is recommended by this article. It's more ideal reflect that the beam's stress situation after has used in vitro pre-stressed reinforcement.
The goal of this article's calculated demonstration is that for reinforce the supporting. Also it may used in reinforce method of vitro pre-stressed to reinforce the instructed durability and using.function.
本文根据现有的体外预应力混凝土试验梁数据,在理论分析的基础上对既有的多组体外预应力筋极限应力简化计算公式进行验证分析。讨论了非预应力筋配筋率、体外预应力筋配筋率、跨高比、混凝土强度、以及加载方式等对体外预应力筋极限应力增量的影响,分析了转向块、预应力束形状以及荷载形式等因素对体外预应力筋二次效应的影响。通过对比分析找出一组与试验结果吻合最好的极限应力计算公式。在此基础上再考虑现行桥梁结构设计的安全系数,即可用以指导桥梁体外预应力结构的工程设计。
通过对体外预应力加固体系受力特点的分析,评价了加固体系正截面抗弯承载力、斜截面抗剪承载力、使用状态下的体外预应力筋应力增量、使用状态下应力变形以及转向块等的计算方法,并分别通过钢筋混凝土梁和预应力混凝土梁的加固算例进行验算。从验算结果来看,本文推荐的体外预应力加固计算方法,较理想的反映了梁体在采用体外预应力加固后的受力情况,可以应用到实际桥梁工程的加固设计。
本文的计算示例均为以承载力加固为目的,也可以采用体外预应力的加固方法对结构的使用功能和耐久性进行加固。
Because of the advantages of simple construction, structural safety and economy, the external prestressing technique has been widely used in the new construction of bridges. Also, Many bridges at service are suffering from crack or over distortion due to corrosion of reinforcement bar and overweight. It is very effective to strengthen these structures using the externally prestressing technique.
According to the present experiment beam of external prestressing.This article mainly analysis the different simplified formula to the ultimate stress of external prestressing tendon on the base of theoretical analysis. Influence of various parameters including ratio of unprestressed reinforcement, ratio of external prestressing tendon, span-depth ratio, compressive strength of concrete, and loading pattern on the ultimate stress in tendon, fps, are investigated in detail. Parameters having important influence on second-order effects of externally prestressed concrete beams as deviators, tendon configuration and load type are evaluated. Then it can find almost suitable calculated formula of the ultimate stress.In this foundation, then reconsiders the safety coefficient to the bridge design.So it can be used to instruct the design of externally prestressed beam.
Through analyse the pressed characters of reforced system within external prestressing,It evaluated the calculational method of normal cross section flexural bearing capacity and normal cross section flexural bearing capacity within reinforced system.Also,it evaluated the calculational method of stress increment of external prestressing tendons,stress deformation and deviator are used.Moreover,It put up separated computations by reinforced examples of RC beams and PC beams.according from the result of checked calculation, reinforce computational method of vitro pre-stressed is recommended by this article. It's more ideal reflect that the beam's stress situation after has used in vitro pre-stressed reinforcement.
The goal of this article's calculated demonstration is that for reinforce the supporting. Also it may used in reinforce method of vitro pre-stressed to reinforce the instructed durability and using.function.
引文
1 M. H. Harajli. Strengthening of concrete beams by external prestressing. PCI Journal. 1993, 38(6):76~88
2李鸿威.体外预应力加固梁桥的试验研究.哈尔滨建筑工程学院硕士学位论文. 1993:43~54
3房贞政,上官萍.预制拼装体外索预应力混凝土连续梁的受力性能探讨.福州大学学报(自然科学版). 1996, 24(4):16-21
4 R. H. Tan, C. K. Ng. Effect of deviator and Tendon Configuration on Behavior of Externally Prestressed Beams. ACI Structural Journal. 1997, 94(1):13~22
5 K. H. Tan,C. K. Ng. Effect of shear in externally prestressed beams. ACI Structural Journal. 1998 95(2):116~128
6王宗林.体外预应力混凝土桥梁极限状态分析.哈尔滨工业大学博士学位论文. 2001:21~60
7孙海,黄鼎业.体外预应力简支梁受力性能研究与非线性分析.土木工程学报. 2000, 33(2):25~29
8 M. H. Harajli, M. E. Mabsout. Response of Externally Post-Tensional Contiuous Members. ACI Structural Journal. 2002, 99(5):671~680
9 A. C. Aparicio, G. Ramos, J. R. Casas. Testing of externally prestressed concrete beams. Engineering Structures. 2002, 24:73~84
10李方元,赵人达.周益云.体外预应力高强混凝土两跨连续梁模型试验.西南交通大学学报. 2002, 37(5):500~504
11张仲先,张耀庭.体外预应力混凝土梁体外筋应力增量的试验与研究.铁道工程学报. 2003, (4):75~80
12李国平,沈殷.体外预应力筋极限应力和有效高度计算方法.土木工程学报. 2007,40(2):47~52
13 K. H. Tan, A. E. Naaman. Strut-and-tie model for externally prestressed concrete beams. ACI Structural Journal. 1993, 90(6):683~691
14 A. C. Aparicio, G. Ramos. Flexural strength of externally prestressed concrete bridges. ACI Structural Journal. 1996, 93(5):512~523
15 M. A. Pisani, E. Nicoli. Beams prestressed with unbonded tendons at ultimate.Canadian Journal of Civil Engineering. 1996, 23(6):1220~1230
16黄侨.公路钢筋混凝土简支梁桥的体外预应力加固技术.人民交通出版社. 1998:33~88
17 M Harajli, N Khairallah and H Nassif. Externally Prestressed Members: Evaluation of Second-order Effects. Journal of Structural Engineering. 1999, 125(10):1151~1161
18牛斌.体外预应力混凝土梁弯曲性能分析.土木工程学报. 1999, 32(4):37~44
19 Ayaho Miyamoto, Katsuji Tei, Hideaki Nakamura And John W. Bull. Behavior of Prestressed Beam Strengthened With External Tendons. Journal of Structural Engineering. 2000,126(9): 1033~1044
20 Xiao-Han Wu And Xilin Lu. Tendon Model For Nonlinear Analysis of Externally Prestressed Concrete Structures. Journal of Structural Engineering. 2001, 127(4):398~405
21楼铁炯.无粘结预应力梁的有限元建模与性能分析研究.浙江大学博士学位论文. 2005:14~24
22 Nihal Ariyawardena And Amin Ghali, F.Asce.Prestressing With Unbonded Internal or External Tendons:Analysis And Computer Model. Journal of Structural Engineering. 2002, 128(12):1493~1501
23方德平.考虑P△效应得体外预应力梁的M-φ分析法.工程力学. 2002, 19(4):113~117
24黄真,刘西拉.预制节段式无粘结预应力混凝土箱梁受弯扭剪共同作用分析.土木工程学报. 2003, 36(6):60~65
25 P R Chakrabarti. Ultimate stress for unbonded post-tensioning tendons in partially prestressed beams. ACI Structural Journal. 1995, 92(6):689~697
26 A. E. Naaman, F. M. Alkhairi. Stress at Ultimate in Unbonded Prestressing Tendons:Part1-Evaluation of the State-of-the-Art. ACI Structural Journal 1991, 89(5):641~651
27 A. E. Naaman, N. Burns, C. French. Stress in Unbonded Prestressed Tendons at Ultimate. ACI Structural Journal. 2002, 99(4):518~529
28 A. E. Naaman, F. M. Alkhairi. Stress at ultimate in unbonded prestressing tendons:Part2-Proposed Methodology. ACI Structural Journal. 1991b, 89(6):683~692
29 ACI Committee 318-02. Building Code Requirements For Reinforced Concrete. Detrioit:American Concrete Institute. 2002
30 M Harajli, N Khairallah and H Nassif. Externally Prestressed Members Evaluation of Second-order Effects. Journal of Structural Engineering. 1999, 125(10):1151~1161
31 M H Harajli. Effect of Span-Depth Ratio on the Ultimate Steel Stress in Unbonded Prestressed Concrete Members. ACI Structure Journal. 1990, 87(3):305~312
32 M. H. Harajli, M. Y. Kanj. Ultimate Flexural Strength of Concrete Member Prestressed with Unbonded Tendon. ACI Structural Journal. 1991, 88(6):663~673
33杜进生,刘西拉.基于结构变形的无粘结预应力筋应力变化研究.土木工程学报. 2003, 36(8):12~19
34 Du Jinsheng, Lu Wenliang and Ji Wenyu. Discussion of Stress in the External Tendons at Ultimate. ACI Structural Journal. 2006, 103(1):149~154
35牛斌.体外预应力混凝土梁极限状态分析.土木工程学报. 2000, (33)3:8~15
36李国平,沈殷.体外预应力筋极限应力和有效高度计算方法.土木工程学报. 2007, 40(2):47~52
37 J. Ament, P. R. Chakrabarti, C. S. Putcha. Comparative statistical study for the ultimate stress in unbonded post tensioning. ACI Structural Journal. 1997, 94(2):211~217
38沈殷.体外预应力混凝土桥梁抗剪承载力研究.同济大学博士学位论文, 2004: 100~130
39王彤.体外预应力混凝土桥梁设计理论研究.哈尔滨工业大学交通科学与工程学院博士学位论文. 2003: 24~30
40张树仁,王宗林.桥梁病害诊断与改造加固设计.人民交通出版社. 2006: 142~158
41徐栋.节段施工体外预应力桥梁的极限强度分析.同济大学博士学位论文. 1999:52~83
42熊学玉.体外预应力结构设计.中国建筑工业出版社. 2005:43~59
43李国平,沈殷.体外预应力混凝土简支梁抗剪承载力计算方法.土木工程学报. 2007, 40(2):64~69
44杨莉.体外预应力混凝土连续梁受力行为研究.西南交通大学博士学位论文. 2005:117~140
45李国平.体外预应力混凝土简支梁剪切性能试验研究.土木工程学报. 2007, 40 (2):58~63
46 G. Ramos, A. C. Aparicio. Ultimate Analysis Of Monolithic And Segmental Externally Prestressedconcrete Bridges. Journal of Bridge Engineering, ASCE. 1996, 1(1): 10~17
47 AASHTO 2004. LRFD Bridge Design Specification. American Association of State Highway and Transportation Officials. Washington D C. 2004:198~230
2李鸿威.体外预应力加固梁桥的试验研究.哈尔滨建筑工程学院硕士学位论文. 1993:43~54
3房贞政,上官萍.预制拼装体外索预应力混凝土连续梁的受力性能探讨.福州大学学报(自然科学版). 1996, 24(4):16-21
4 R. H. Tan, C. K. Ng. Effect of deviator and Tendon Configuration on Behavior of Externally Prestressed Beams. ACI Structural Journal. 1997, 94(1):13~22
5 K. H. Tan,C. K. Ng. Effect of shear in externally prestressed beams. ACI Structural Journal. 1998 95(2):116~128
6王宗林.体外预应力混凝土桥梁极限状态分析.哈尔滨工业大学博士学位论文. 2001:21~60
7孙海,黄鼎业.体外预应力简支梁受力性能研究与非线性分析.土木工程学报. 2000, 33(2):25~29
8 M. H. Harajli, M. E. Mabsout. Response of Externally Post-Tensional Contiuous Members. ACI Structural Journal. 2002, 99(5):671~680
9 A. C. Aparicio, G. Ramos, J. R. Casas. Testing of externally prestressed concrete beams. Engineering Structures. 2002, 24:73~84
10李方元,赵人达.周益云.体外预应力高强混凝土两跨连续梁模型试验.西南交通大学学报. 2002, 37(5):500~504
11张仲先,张耀庭.体外预应力混凝土梁体外筋应力增量的试验与研究.铁道工程学报. 2003, (4):75~80
12李国平,沈殷.体外预应力筋极限应力和有效高度计算方法.土木工程学报. 2007,40(2):47~52
13 K. H. Tan, A. E. Naaman. Strut-and-tie model for externally prestressed concrete beams. ACI Structural Journal. 1993, 90(6):683~691
14 A. C. Aparicio, G. Ramos. Flexural strength of externally prestressed concrete bridges. ACI Structural Journal. 1996, 93(5):512~523
15 M. A. Pisani, E. Nicoli. Beams prestressed with unbonded tendons at ultimate.Canadian Journal of Civil Engineering. 1996, 23(6):1220~1230
16黄侨.公路钢筋混凝土简支梁桥的体外预应力加固技术.人民交通出版社. 1998:33~88
17 M Harajli, N Khairallah and H Nassif. Externally Prestressed Members: Evaluation of Second-order Effects. Journal of Structural Engineering. 1999, 125(10):1151~1161
18牛斌.体外预应力混凝土梁弯曲性能分析.土木工程学报. 1999, 32(4):37~44
19 Ayaho Miyamoto, Katsuji Tei, Hideaki Nakamura And John W. Bull. Behavior of Prestressed Beam Strengthened With External Tendons. Journal of Structural Engineering. 2000,126(9): 1033~1044
20 Xiao-Han Wu And Xilin Lu. Tendon Model For Nonlinear Analysis of Externally Prestressed Concrete Structures. Journal of Structural Engineering. 2001, 127(4):398~405
21楼铁炯.无粘结预应力梁的有限元建模与性能分析研究.浙江大学博士学位论文. 2005:14~24
22 Nihal Ariyawardena And Amin Ghali, F.Asce.Prestressing With Unbonded Internal or External Tendons:Analysis And Computer Model. Journal of Structural Engineering. 2002, 128(12):1493~1501
23方德平.考虑P△效应得体外预应力梁的M-φ分析法.工程力学. 2002, 19(4):113~117
24黄真,刘西拉.预制节段式无粘结预应力混凝土箱梁受弯扭剪共同作用分析.土木工程学报. 2003, 36(6):60~65
25 P R Chakrabarti. Ultimate stress for unbonded post-tensioning tendons in partially prestressed beams. ACI Structural Journal. 1995, 92(6):689~697
26 A. E. Naaman, F. M. Alkhairi. Stress at Ultimate in Unbonded Prestressing Tendons:Part1-Evaluation of the State-of-the-Art. ACI Structural Journal 1991, 89(5):641~651
27 A. E. Naaman, N. Burns, C. French. Stress in Unbonded Prestressed Tendons at Ultimate. ACI Structural Journal. 2002, 99(4):518~529
28 A. E. Naaman, F. M. Alkhairi. Stress at ultimate in unbonded prestressing tendons:Part2-Proposed Methodology. ACI Structural Journal. 1991b, 89(6):683~692
29 ACI Committee 318-02. Building Code Requirements For Reinforced Concrete. Detrioit:American Concrete Institute. 2002
30 M Harajli, N Khairallah and H Nassif. Externally Prestressed Members Evaluation of Second-order Effects. Journal of Structural Engineering. 1999, 125(10):1151~1161
31 M H Harajli. Effect of Span-Depth Ratio on the Ultimate Steel Stress in Unbonded Prestressed Concrete Members. ACI Structure Journal. 1990, 87(3):305~312
32 M. H. Harajli, M. Y. Kanj. Ultimate Flexural Strength of Concrete Member Prestressed with Unbonded Tendon. ACI Structural Journal. 1991, 88(6):663~673
33杜进生,刘西拉.基于结构变形的无粘结预应力筋应力变化研究.土木工程学报. 2003, 36(8):12~19
34 Du Jinsheng, Lu Wenliang and Ji Wenyu. Discussion of Stress in the External Tendons at Ultimate. ACI Structural Journal. 2006, 103(1):149~154
35牛斌.体外预应力混凝土梁极限状态分析.土木工程学报. 2000, (33)3:8~15
36李国平,沈殷.体外预应力筋极限应力和有效高度计算方法.土木工程学报. 2007, 40(2):47~52
37 J. Ament, P. R. Chakrabarti, C. S. Putcha. Comparative statistical study for the ultimate stress in unbonded post tensioning. ACI Structural Journal. 1997, 94(2):211~217
38沈殷.体外预应力混凝土桥梁抗剪承载力研究.同济大学博士学位论文, 2004: 100~130
39王彤.体外预应力混凝土桥梁设计理论研究.哈尔滨工业大学交通科学与工程学院博士学位论文. 2003: 24~30
40张树仁,王宗林.桥梁病害诊断与改造加固设计.人民交通出版社. 2006: 142~158
41徐栋.节段施工体外预应力桥梁的极限强度分析.同济大学博士学位论文. 1999:52~83
42熊学玉.体外预应力结构设计.中国建筑工业出版社. 2005:43~59
43李国平,沈殷.体外预应力混凝土简支梁抗剪承载力计算方法.土木工程学报. 2007, 40(2):64~69
44杨莉.体外预应力混凝土连续梁受力行为研究.西南交通大学博士学位论文. 2005:117~140
45李国平.体外预应力混凝土简支梁剪切性能试验研究.土木工程学报. 2007, 40 (2):58~63
46 G. Ramos, A. C. Aparicio. Ultimate Analysis Of Monolithic And Segmental Externally Prestressedconcrete Bridges. Journal of Bridge Engineering, ASCE. 1996, 1(1): 10~17
47 AASHTO 2004. LRFD Bridge Design Specification. American Association of State Highway and Transportation Officials. Washington D C. 2004:198~230