摘要
混凝土结构的维修加固已经成为当前工程领域的一项重要内容，所以新老混凝土结合面受力性能的研究对于保证混凝土修补结构的安全性具有深远的意义。
新老混凝土之间的良好结合是混凝土修补成功的关键所在，目前国内外的研究中绝大部分是通过二者的粘结作用使其结合成为整体共同受力。而实际工程中仅仅依靠粘结力往往达不到理想的结合程度。因此，本文研究的是加强新老混凝土结合，弥补粘结力不足的一种新方法，即采用机械连接件将新老混凝土结合在一起的方法。
新老混凝土的粘结实际是弹性模量不同的两种材料——即双材料的结合问题。本文通过数值模拟计算结果表明，在规范规定的修补结构新老混凝土强度等级差值范围内，新老混凝土弹性模量相差不大的情况下，新老混凝土粘结劈拉强度可近似采用整体混凝土劈拉强度计算公式。
进行了新老混凝土结合的劈拉强度试验。对比了老混凝土表面处理相同的情况下，不同浇筑方位对无机械连接件试件劈拉强度的影响；机械连接件对劈拉强度的影响；不同植筋材料对劈拉强度的影响。
分析了不同浇筑方位对劈拉试件强度造成影响的原因以及机械连接件在劈拉加载时的受力机理。
对比相同界面粗糙程度下，机械连接件对抗剪强度的影响；对比在加机械连接件的试块中，界面剂——水泥膨浆的影响；对比各新旧结合试块抗剪强度与整体伴随试块抗剪强度的差别。
通过测量钢筋在受剪时候应变，得出钢筋的荷载—变形曲线，对机械连接件的受力原理做了分析；分析了膨胀水泥净浆作为界面剂时对于试件抗剪强度的增强机理。
The repair and strengthening of concrete structure has become an important engineering domain .So the study of adhesive performance of young and old concrete has far-reaching meaning for the security of repaired structure.
Where the shoe pinches of the repair success is all right combination of young and old concrete.Presently,most of the researches inside and outside country made the two into one to against force through felt.In practice,however,it can't obtain ideal bond capacity only depend on adherence.Thus,this paper bring forward a young method to make up the lack of felt capacity-use mechanical joint element to link young and old concrete.
In fact,the adherence of young and old concrete belongs to the adherence research work of bimaterial.The simulation calculation shows that in the range of criterion provision of young and old concrete that the formula for calculating the splitting tensile strength of a monolithic concrete specimen can be used to a concrete specimen of young and old concrete when the difference of elastic modulus of young and old concrete is small.
The cleavage strength test has been carried out to investigate the effect of pour direction for the strength of specimen without mechanical joint element ;the effect of mechanical joint element for the cleavage strength;the effect of different materials which were used to embedding bars for the cleavage strength. All the interface of specimens we mentioned above had the same roughness.
The reasons of different pour direction effects for the cleavage strength has was analyzed,so did the mechanism of mechanical joint element in the cleavage test.
In the situation of same roughness interface,compared the shear strength of specimens with mechanical joint element and that of without;Compared the shear strength of specimens with adhesive agent and without adhesive agent when there were mechanical joint element in the specimens. Compared the shear strength of specimens
that was made of young and old concrete and which was monolithic.
The load-stain curve of bar was obtained in the shear strength test. The mechanism of mechanical joint element in the shear test was analyzed. Strengthen mechanism of adhesive agent-expand cement paste.
引文
[1] 邱小坛，周燕．旧建筑物的检测加固与维护．地震出版社，1991．P28-35
[2] 张富春，林志伸等编著．建筑物的鉴定加固与改造．中国建筑工业出版社，1992．9．P19-24
[3] 中国工程建设标准化协会标准．混凝土结构加固技术规范(CECS25：90)．中国计划出版社，1991
[4] 姚祖康，朱以敬编著．道路路面工程．中国建筑工业出版社，1987．12
[5] Emmons, P. H., Vaysburd, A. M., The total system concept—necessary for improving the performance of repaired structures, Concrete International. March, 1995
[6] Sprinkel, M. M., Thermal compatibility of thin polymer—concrete overlays, Transportation Research Board 899. Washington, D. C. : 1983. P64-72
[7] 大连理工大学．“新老砼的粘结机理和测试方法研究”年度研究报告．1997．1
[8] [日]小林一辅著，邹崇富译，广钟岩校．纤维补强混凝土．中国铁道出版社，北京：1985
[9] Mander, R. F., Use of resins in road and bridge construction and repair, International Journal of Cement CompSsites ang Lightweight Concrete, Vol. 3, No. 1, Feb. 1981. P27-39
[10] Johan Silfwerbrand. Improving concrete bond in repaired bridge decks. Concrete International, Sept. 1990, P61-66
[11] 唐敏 译．高速公路桥梁的修补与加固．国外建筑科学．Vol．13，No．4．1995．P15-16
[12] D. N. Trikha, 许贤敏译．受损的混凝土梁之修补与增强．国外建筑科学，Vol．6，No．2，1993，P15-24
[13] J. A. Brickley, R. Liscio. Repair and Protection system for parking structures, Concrete International: Design &Construction, Vol. 10, No. 4, April. 1988. P21-28
[14] 陈玉锦等．特大火灾后的建筑结构鉴定和抢修加固方法．建筑技术，1995年第6期．P373-374
[15] J. Bijen and T. Salet. Adherence of young concrete to old concrete development of tools for engineering. Adherence of young on old concrete, edited by Folker H, Wittmann, AEDIFICATIO, Verlag, Unterengstingen, 1994
[16] E. Walter and P. Meier, The use of mechanical dowels as bond elements between new and old concrete. Adherece of young on old concrete, edited by Folker H. Wittmann, AEDIFICATIO, Verlag, Unterengstingen, 1994
[17] F. Seible and C. T. Latham. Horizontal load transfer in structural concrete bridge deck overlays. Journal of Structural Engineering, Vol. 116 No. 10 Oct. 1990
[18] Robert A. Bass and James O. Jirsa, Shear tranfer across new and existing concrete interfaces, ACI Structural Journal Vol. 86. No. 4 July-Aug. 1989 P383-393
[19] Johan Silfwerbrand. Improving concrete bond in repaired bridge decks, Concrete International, Sept. 1990. P61-66
[20] Uherkovich I. Questions Concerning the Long Term Behavior of Concrete Repair. Adherence of Young on Old Concrete, Edited by Wiltnann Folker H. AEDIFICAO. 1994. P177-181
[21] 刘运明，熊光晶，谢慧才．下补新老混凝土粘结界面完全劣化梁的工作性能．土木工程学报，2000(2)．P109-112
[22] 刘金伟，谢慧才．修补后龄期对新老混凝土粘结强度的影响．土木工程学报，2001(1)：P30-32
[23] 刘金伟，谢慧才，熊光晶．新老混凝土粘结界面耐久性能的试验研究．混凝土，2001(2)P35-38
[24] 敖进涛，谢慧才，熊光晶，等．影响新老混凝土界面粘结强度的主要因素．工程力学(增刊，第二卷)，1997：P328～333
[25] Hofbeck, J.A.,etal. Shear transfer in reinforced concrete. ACI Journal, Feb. 1969
[26] Simon Austin, et al, Tensile bond testing of concrete repairs. Materials and Structures, 1995, 28: P249—259
[27] 工程施工规范(工程建设规范汇编28)．普通混凝土力学性能试验方法(GBJ81-85)，中国建筑工业出版社
[28] 刘金伟，熊光晶，谢慧才．新老混凝土修补界面方位对粘结强度的影响．工业建筑，2001年第31卷第5期
[29] 罗福午．建筑结构概念体系与估算．清华大学出版社：1999．5．P123-126
[30] 车宏亚．钢筋混凝土结构原理．天津大学出版社：1995．11．P17-36
[31] 陈改新，黄国兴．水工混凝土冻融破坏的修补技术．水利水电技术，Vol．28，No．3，1997
[32] Hilsdorf, H.K. etal. Fracture mechanics applications in the analysis of concrete repair and protection system. Adherence of Young on Old Concrete, edited by F.H. Wittmann, 1994
[33] 赵志方．新老混凝土粘结机理和测试方法．大连理工大学博士学位论文，1998，8
[34] 冷轧带肋钢筋混凝土结构技术规程．JGJ 95—95，中国建筑工业出版社
[35] Hughes B P, Chapman G P. The Complete Stress-Strain Curve for Concrete in Tension. RILEM Belletin (Paris). New Series No 30, March 1966. P95～97
[36] Gopalaratnam V S, Shah S P. Softening Response of Plain Concrete in Direct Tension. ACI, 1985. 82 (3): 310～323
[37] 过镇海，张秀琴．混凝土受拉应力-变形全曲线地试验研究．建筑结构学报，1988(4)：P45～53
[38] Carneiro F.L. and Barcellos. A.,Tensile strength of Concrete. RILEM Belletin, No 13, International Association of Testing and Research Laboratories for Meterial ang Structures, Paris, 1953: P97～123
[39] Wright, P.J.F.,Comments on an indirect tension test on concrete
cylinders. Magazine of Concrete Research, Vol. 7, No. 2, July, 1955: P87～96
[40] 赵国藩．混凝土圆柱体抗拉强度的试验研究．土木工程，1957年第五期：P235～239
[41] 龚曙光．ANSYS基础应用及范例解析．机械工业出版社，1991：P1～17
[42] Hsu TTC, et al. Microcracking of Plain Concrete and the Shape of the Stress-Strain Curve. ACI Feb. 1963: P209～224
[43] Liu TCY, et al. Stress-Strain Response and Fracture of Concrete in Uniaxial and Biaxial Compression. ACI, May. 1972: P291～295
[44] Neville A M．李国泮等译．混凝土的性能．北京：中国建筑工业出版社，1983
[45] L' Hermite R．于宏译．混凝土工艺问题．北京：中国建筑工业出版社，1964
[46] 刘尔烈．有限单元法及程序设计．天津大学出版社，1999．7：P1～P2
[47] Ichiro ADACHI, Shigemi SAKODA. Teruo YAHIRO. An Experimental Study of the Treatment of Construction joints in Concrete Structures Use Water Jet Method, 4thPRICWJT 1995
[48] John A. Wells. Robert D. Stark, Dimos Polyzois. Getting Better Bond in Concrete Overlays. Concrete International, 1999, (3):P49-52
[49] Johan Silfwerbrand. Improving Concrete Bond in Repaired Bridge Deck. Concrete International, 1990, (9): P61-66
[50] 熊光晶，姜浩，陈立强，等，新老混凝土修补界面层粘结质量的改善途径．工业建筑，2001年第31卷第11期
[51] 管大庆，等，界面处理对新老砼粘结性能的影响．混凝土，1994，(5)
[52] 足立一郎．用喷砂(丸)法处理新旧砼粘结面的研究．昭和60年7月
[53] CEN TC104. Draft European Standard on Products and Systems for the Protection and Repair of Concrete Structures, CEN/TC104/WG8/TG2, Draft ENYY, art 39, oct. 1992
[54] 纪细煌．高强混凝土的断裂与内部结构的关系研究．清华大学博士学位论文，1994
[55] 于跃海．分形及分数维理论在新老混凝土粘结机理研究中的应用．大连理工大学硕士学位论文，1998
[56] M. H. Fiebrich. Influence of the surface roughness on the adherence between concrete and gunitemortar overlays. Adherence of young on old concrete, edited by Folker H. Wittmann, AEDIFICATIO Verlag, Unterengstringer, 1994.
[57] 谢慧才，李庚英，熊光晶．新老混凝土界面粘结力形成机．硅酸盐通报，2003年第三期
[58] Chen Pu-Woei. Fu Xuli, Improving the bonding between old and new concrete by adding carbon fibers to the new concrete. Cement and Concrete Research 1995, 25(3): P491～496
[59] King J., Wilson A. If it's still standing, it can be repaired. Concrete Construction, 1988, 3(7): P643～650
[60] P. Ciferni. Shrinkage compensated mortars: an approach to concrete structural repair. Adherence of young on old concrete, edited by Folker H. Wittmann, AEDIFICATIO Verlag Unterengstringen, 1994
[61] Emmons, P. H., et al, Concrete repair in the future turn of the century-any problems? Concrete International, March, 1994
[62] 谢慧才，李庚英，熊光晶．新老混凝土粘结界面的微结构及与集料-水泥界面的差异．工业建筑，2003年第33卷第1期
[63] 李庚英，谢慧才，熊光晶．新老混凝土粘结界面的微结构及与宏观力学性能的关系．混凝土，1999(6)：P13～18
[64] M. H. Fiebrich. Scientificaspects of adhesion phenomena in the interface mineral substrate-polymers. Adherence of Young on Old Concrete, edited by F.H. Wittmann, 1994
[65] J. Bilen, T. Salet. Adherence of young concrete on old concrete-development of tools for engineering, edited by F.H. Wittmann, 1994
[66] 微观结构的分析和测试，北京：清华大学出版社出版，1997．
[67] Plum D. R. The behaviour of polymer materials in concrete repair, and factors in fluencing selction. The Structural Engineer, 1990, 68(17): P337～345
[68] 水利水电科学研究院译．混凝土的强度和破坏译文集，北京：水利出版社，1982，5
[69] 廉慧珍，童良，陈恩义．建筑材料物相研究基础[M]．北京：清华大学出版社，1996．P131 143．
[70] 袁群，赵国藩．用神经网络方法预测新老混凝土的粘结强度．建筑材料学报，第4卷第2期2001年6月
[71] 过镇海．钢筋混凝土原理．清华大学出版社，1999．3：P39～45