modeling of chloride penetration onto concrete structures under flexual cyclic load and tidal environment

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modeling of chloride penetration onto concrete structures under flexual cyclic load and tidal environment

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การจําลองการซึมผานของคลอไรดในโครงสรางคอนกรีต ภายใตการรับแรงดันแบบวัฏจักรและสภาพแวดลอมแบบน้ําขึ้นน้ําลง นายเมียนวัน เจิ่น วิทยานิพนธนี้เปนสวนหนึ่งของการศึกษาตามหลักสูตรปริญญาวิศวกรรมศาสตรดุษฎีบัณฑิต สาขาวิชาวิศวกรรมโยธา ภาควิชาวิศวกรรมโยธา คณะวิศวกรรมศาสตร จุฬาลงกรณมหาวิทยาลัย ปการศึกษา 2551 ลิขสิทธิ์ของจุฬาลงกรณมหาวิทยาลัย MODELING OF CHLORIDE PENETRATION INTO CONCRETE STRUCTURES UNDER FLEXURAL CYCLIC LOAD AND TIDAL ENVIRONMENT Mr. MIEN VAN TRAN A Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Program in Civil Engineering Department of Civil Engineering Faculty of Engineering Chulalongkorn University Academic Year 2008 Copyright of Chulalongkorn University Thesis Title Modeling of chloride penetration into concrete structures under flexural cyclic load and tidal environment By Mr. Mien Van Tran Field of study Civil Engineering Thesis Principal Advisor Associate Professor Boonchai Stitmannaithum, D.Eng. Thesis Co-Advisor Professor Toyoharu NAWA, D.Eng. Accepted by the Faculty of Engineering, Chulalongkorn University in Partial Fulfillment of Requirements for the Doctoral Degree ……………………………………Dean of the Faculty of Engineering (Associate Professor Boonsom Lerdhirunwong, Dr.Ing) THESIS COMMITTEE …………………………………………. Chairman (Professor Ekasit Limsuwan, Ph.D) …………………………………………. Thesis Principal Advisor (Associate Professor Boonchai Stitmannaithum, D.Eng.) …………………………………………. Thesis Co-Advisor (Professor Toyoharu NAWA, D.Eng.) …………………………………………. Member (Associate Professor Phoonsak Pheinsusom, D.Eng) …………………………………………. Member (Associate Professor Teerapong Senjuntichai, Ph.D) …………………………………………. Member (Associate Professor Suvimol Sujjavanich, Ph.D) iv เมียนวัน เจิ่น : การจําลองการซึมผานของคลอไรดในโครงสรางคอนกรีตภายใตการรับแรงดัด แบบวัฏจักรและสภาพแวดลอมแบบน้ําขึ้นน้ําลง (MODELING OF CHLORIDE PENETRATION INTO CONCRETE STRUCTURES UNDER FLEXURAL CYCLIC LOAD AND TIDAL ENVIRONMENT). อ. ที่ปรึกษาวิทยานิพนธหลัก : รศ.ดร. บุญไชย สถิตมั่นในธรรม, อ. ที่ปรึกษา วิทยานิพนธรวม: ศ.ดร. โทโยฮารุ นาวา, 157 หนา. ในสภาพแวดลอมทางทะเลความเสียหายของโครงสรางคอนกรีตเสริมเหล็กโดยมากเกิดจากคลอไรด ซึ่งทําใหเกิด การสึกกรอนของเหล็กเสริมโครงสราง โดยสภาพความเสียหายของโครงสรางคอนกรีตนั้นจะขึ้นอยูกับทั้งน้ําหนักบรรทุก และสภาพแวดลอมกระทํารวมกัน เมื่อโครงสรางคอนกรีตรับน้ําหนักบรรทุกจนเกิดการแตกราวในโครงสรางคอนกรีต อัน เปนผลใหการซึมผานของคลอไรดเขาไปยังโครงสรางคอนกรีตมีอัตราเพิ่มสูงขึ้นอยางรวดเร็วจะทําใหอายุการใชงานของ โครงสรางคอนกรีตเสริมเหล็กลดลงอยางมีนัยสําคัญ ในอดีตมีการศึกษาดานพฤติกรรมเชิงกลของโครงสรางคอนกรีตและ การเสื่อมสภาพของโครงสรางคอนกรีตแลวเปนจํานวนมาก อยางไรก็ตามแบบจําลองที่เสนอขึ้นเหลานั้นมิไดพิจารณาผล จากการกระทําของน้ําหนักบรรทุกทางกลและสภาพแวดลอมรวมกันแตอยางใด วัตถุประสงคของงานวิจัยนี้คือการพัฒนาแบบจําลองการซึมผานของคลอไรดเขาสูเนื้อคอนกรีตภายใตการรับแรง ดัดแบบวัฎจักรและสภาพแวดลอมแบบน้ําขึ้นน้ําลง แบบจําลองนี้ตั้งอยูบนพื้นฐานทางทฤษฎีและผลการทดสอบการซึม ผานของคลอไรด ปริมาณคลอไรดและการรับแรงดัดแบบวัฎจักร โดยแรงดัดแบบวัฎจักรในการทดสอบใชแรงดัดจาก ระดับรอยละ50 ถึงรอยละ80 ของกําลังดัด แบบจําลองการแตกราวเสมือนไดรับการปรับปรุงเพื่อทํานายการเสียรูปจากการ ลาของคานคอนกรีตภายใตแรงดัด การทดสอบใชซีเมนตสี่ชนิดในการตรวจสอบความสามารถในการจับยึดคลอไรดอิออน (Chloride Binding Isotherms) สภาพแวดลอมแบบน้ําขึ้นน้ําลงจําลองโดยการทดสอบในสภาพเปยก 12 ชั่วโมง และ แหง 12 ชั่วโมง ผลการทดสอบความสามารถในการจับยึดคลอไรดอิออนแสดงใหเห็นถึงความสัมพันธแบบเชิงเสนระหวางผล การทดสอบระยะสั้นและระยะยาว ทั้งนี้ซีเมนตปอตแลนดชนิดธรรมดา (OPC) มีความสามารถในการจับยึดคลอไรดอิออน (Bind Chloride Ions) สูงสุด ขณะที่ซีเมนตประเภทความรอนต่ํามีการจับยึดคลอไรดอิออนนอยที่สุด แบบจําลองที่เสนอ ขึ้นใหมนี้แสดงใหเห็นวาการรับแรงดัดแบบทําซ้ําทําใหคลอไรดซึมผานคอนกรีตมากขึ้น ระดับการรับแรงดัดที่สูงขึ้นยิ่งทํา ใหการซึมผานของคลอไรดเร็วขึ้น การทํานายโดยแบบจําลองสอดคลองเปนอยางดีกับผลการทดสอบเมื่อใชพารามิเตอร ความหนาแนนการแตกราว ( μ ) และพารามิเตอรดานการบิดงอ ( τ ) ภาควิชา วิศวกรรมโยธา ลายมือชื่อนิสิต สาขาวิชา วิศวกรรมโยธา ลายมือชื่อ อ. ที่ปรึกษาวิทยานิพนธหลัก ปการศึกษา 2551 ลายมือชื่อ อ. ที่ปรึกษาวิทยานิพนธรวม v # # 4871874721 MAJOR CIVIL ENGINEERING KEYWORDS: MODEL / CHLORIDE PENETRATION / CONCRETE / FLEXURAL CYCLIC LOAD / TIDAL ENVIRONMENT MIEN VAN TRAN: MODELING OF CHLORIDE PENETRATION INTO CONCRETE STRUCTURES UNDER FLEXURAL CYCLIC LOAD AND TIDAL ENVIRONMENT. ADVISOR: ASSOC.PROF. BOONCHAI STITMANNAITHUM, D.ENG. CO-ADVISOR: PROF. TOYOHARU NAWA, D.ENG., 157 pp. In marine environment, the deterioration of concrete structures is mainly due to chloride induced corrosion. With real concrete structures, the deterioration is controlled by the combination of mechanical load and climatic load. The mechanical load results cracks in concrete structures. The cracks accelerate the chloride penetration into concrete structures. As a result, the service life of concrete structures will be reduced considerably. There were many models proposed to predict the deterioration of concrete structures. However, these models are not reliable due to not having simultaneous combination of mechanical and climatic loads. In this research, a model, which simulates the chloride ingress into plain concrete, using different cement types, under flexural cyclic load and tidal environment, was proposed. This model is based on theoretical analysis and experiments of chloride diffusion test, chloride content test and flexural cyclic loading test. Flexural cyclic load is applied from 50% to 80% of to ultimate bending load. Fictitious crack model is adopted to predict fatigue crack growth of plain concrete beam under flexural fatigue. Experimental results show the linear relation between results of short-term and long-term test of chloride diffusion coefficient. Of the four common cement types, Ordinary Portland cement is the best cement type using for concretes in term of the chloride induced corrosion resistance because of the highest capacity to bind chloride ions. The proposed model shows that the flexural cyclic load accelerates chloride penetration into concrete. The higher the flexural load level, SR, the faster chloride penetration occurred. The model predictions fit well with experimental results when the crack density parameter, μ , and the tortuosity parameter, τ , are introduced. Department: CIVIL ENGINEERING……… Student’s signature: ………………………. Field of study: CIVIL ENGINEERING…… Advisor’s signature: ………………………. Academic year: 2008………………………. Co-advisor’s signature: …………………… vi ACKNOWLEDEMENTS JICA is most sincerely thanked for funding this Ph.D project through AUN/SEED-Net program. Without the financial support given to me by JICA, this project would never have become about. I wish to express my honest gratitude to my advisor, Assoc.Prof. Boonchai Stitmannaithum, to the staff and my colleagues at Department of Civil Engineering (CU) for their guidance, encouragement and support during my research. I also wish to express my gratitude to Prof. Toyoharu NAWA for interesting discussions, as well as for helping me improve my model, and for his support of a useful year of doing research in his Laboratory at Hokkaido University, Japan. Furthermore, I would like to express my gratitude to Assoc.Prof. Kiyofumi KURUMISAWA and to my friends at Resources and Eco Materials Engineering Laboratory, Hokkaido University, Japan, for their help and friendliness. Finally, I would like to thank my sending institution – HoChiMinh City University (HCMUT) and host institution - Chulalongkorn University (CU) for giving me the opportunity to study Ph.D degree under AUN/SEED-Net program. TABLE OF CONTENTS Page Abstract (Thai) iv Abstract (English) v Acknowledgements vi Table of contents vii List of Tables ix List of Figures xi CHAPTER I INTRODUCTION 1 1.1 Introduction 1 1.2 The objective of study 2 1.3 The scope of study 3 1.4 Literature review 3 1.5 Methodology 24 1.6 Originality and expected results of research 26 1.7 Concluding remarks 27 CHAPTER II DEVELOPMENT OF MODEL 28 2.1 Prediction of mechanical and physical properties of concrete 28 2.2 Fatigue and fatigue deformation of plain concrete beam under flexural cyclic load 32 2.3 Prediction of chloride diffusion coefficient under fatigue 41 2.4 Prediction of chloride penetration into concrete under flexural cyclic load and tidal environment 43 2.5 Concluding remarks 57 CHAPTER III CHLORIDE BINDING ISOTHERMS OF CEMENTS 58 3.1 Procedures for determination of chloride binding isotherms of cements 58 3.2 Propose chloride binding isotherms of cements 62 3.3 Concluding remarks 73 viii CHAPTER IV CHLORIDE PENETRATION INTO CONCRETE STRUCTURES UNDER FLEXURAL CYCLIC LOAD AND TIDAL ENVIRONMENT 74 4.1 Designed mechanical and physical properties of concretes 74 4.2 Prediction of fatigue crack growth under flexural cyclic load 75 4.3 Prediction of chloride diffusion coefficient under fatigue 79 4.4 Prediction of chloride penetration under fatigue and tidal environment 83 4.5 Concluding remarks 95 CHAPTER V EXPERIMENTAL VERIFICATION 96 5.1 Experimental program 97 5.2 Experimental results and verifications of model 101 5.3 Concluding remarks 118 CHAPTER VI CONCLUSIONS 119 6.1 Conclusions 119 6.2 Applications of results 120 6.3 Limitations 121 6.4 Recommendations 122 REFERENCES 123 APPENDIX 127 BIOGRAPHY 157 ix LIST OF TABLES Table 2.1 Parameters of plain concrete 39 Table 3.1 Chemical and physical properties of various cement types 59 Table 3.2 The estimated contents of types of cement used to cast cubic specimen 60 Table 4.1 Designed mechanical and physical properties of concrete 74 Table 4.2 Input parameters of numerical analysis of fatigue deformations 76 Table 4.3 Prediction of D tot of plain concrete in the tension zone with the number of cycles 82 Table 4.4 Input parameters used in the numerical analysis of chloride penetration into plain concrete using different cements and exposed to tidal environment. 85 Table 4.5 Input parameters used in the numerical analysis of chloride penetration into plain concrete subjected to coupling flexural cyclic loads and tidal cycles 88 Table 4.6 Input parameters used to predict the initial corrosion time of the concrete exposed to tidal cycles and flexural cyclic load 91 Table 5.1 Mixture proportions used in research 97 Table 5.2 Diffusion coefficient values given by short-term test, concrete cured at 28 days 101 Table 5.3 Diffusion coefficient values given by long-term test, concrete cured at 28 days 102 Table 5.4 Best fitted values of D 28 and m for concrete mixtures 104 Table 5.5 Mechanical and physical properties of concrete 105 Table 5.6 Flexural cyclic loads applied to concrete beams with different load levels 106 Table 5.7 Cyclic flexural behavior of plain concrete beams of different mixture proportions 107 Table 5.8 Predictions of crack widths and experimental crack widths 109 Table 5.9 The effects of flexural cyclic load on chloride diffusion coefficients 112 Table B.1 The results of XRD-Rietveld analysis of sample I-1 131 x Table B.2 The results of XRD-Rietveld analysis of sample I-2 131 Table B.3 The results of XRD-Rietveld analysis of sample I-3 132 Table B.4 The results of XRD-Rietveld analysis of sample I-4 132 Table B.5 The results of XRD-Rietveld analysis of sample II-1 133 Table B.6 The results of XRD-Rietveld analysis of sample II-2 133 Table B.7 The results of XRD-Rietveld analysis of sample II-3 134 Table B.8 The results of XRD-Rietveld analysis of sample II-4 134 Table B.9 The results of XRD-Rietveld analysis of sample III-1. 135 Table B.10 The results of XRD-Rietveld analysis of sample III-2. 135 Table B.11 The results of XRD-Rietveld analysis of sample III-3. 136 Table B.12 The results of XRD-Rietveld analysis of sample III-4. 136 Table B.13 The results of XRD-Rietveld analysis of sample IV-1 137 Table B.14 The results of XRD-Rietveld analysis of sample IV-2 137 Table B.15 The results of XRD-Rietveld analysis of sample IV-3 138 Table B.16 The results of XRD-Rietveld analysis of sample IV-4 138 Table B.17 Experimental data of chloride binding isotherms of four cement types 139 [...]... and exposed to tidal environment for 5 years, w/c=0.4 87 xiii Figure 4.13 Prediction of chloride profiles of concretes subjected to cyclic load and 5 year exposure to tidal environment, w/c=0.4 89 Figure 4.14 Prediction of chloride profiles of concretes subjected to cyclic load and 5 year exposure to tidal environment, w/c=0.5 90 Figure 4.15 Chloride profiles of the concrete at 50mm... tide and different load levels of flexural cyclic load .92 Figure 4.16 Chloride profiles of concrete at 50mm cover depth exposed to tide and SR=0, 0.5 .93 Figure 4.17 Chloride profiles of concrete at 50mm cover depth exposed to tide and SR=0, 0.6 .93 Figure 4.18 Chloride profiles of concrete at 50mm cover depth exposed to tide and SR=0, 0.7 .94 Figure 4.19 Chloride. .. following: 1 Develop a model to predict the chloride penetration and the initial corrosion time of concrete structures which are subjected to the combination of flexural cyclic loading and marine environment 2 Experimental study of chloride penetration into concrete with the simultaneous combination of flexural cyclic loading and marine environment With viewpoint of safety, the initial corrosion time is... flexural cyclic loading of concrete structures in the simulated marine environment – tidal environment 3 Experiments of chloride diffusion are made for concrete structures subjected to cyclic loading and non-loading 4 Experiments of chloride diffusion by short-term and long-term test 5 Experiments of chloride contents are made to set up chloride binding capacity 6 Experiments of X-ray diffraction Rietveld... analysis for Friedel’s salt and of EPMA (Electron probe micro analysis) for chloride ion distribution before and after washing 7 Verify model of predicting the chloride penetration and the initial corrosion period of concrete structures under combination actions of cyclic loading and tidal environment 1.4 Literature review Up to now, transport properties and models of transport of aggressive ions coupling... width and number of cycles, M1 76 Figure 4.2 Predictions of relationships of crack width and number of cycles, M2 77 Figure 4.3 Predictions of relationships of crack width and number of cycles, M3 77 Figure 4.4 Predictions of relationships of crack length and number of cycles, M1 .78 Figure 4.5 Predictions of relationships of crack length and number of cycles, M2 .78 Figure 4.6 Predictions of relationships... of increasing the number and hugeness of concrete structures, which are exposed to deeper and rougher seawater, this demands on the safety and long-term durability As a result, it is necessary to consider seriously the durability of concrete in marine environment The serviceability and durability of concrete structures in marine environment are governed by many mechanisms of deterioration such as chloride. .. zone, splash zone and submerged zone Of these four zones, tidal zone and splash zone are the most severe ones to corrosion of concrete structures In durability design of concrete structure in marine environment, with the viewpoint of durability of concrete, the first period of corrosion is chosen in design procedure of concrete structures In the initial corrosion period, corrosion of reinforcement will... Bertolini, 2003) 2 In real concrete structures, damage is controlled by combination of mechanical actions and environmental actions The cracks in concrete structures may be formed when concrete structures are subjected to mechanical action As the results, in marine environment, chloride penetration into concrete structures is accelerated, and the service life of concrete structures will be reduced... this research is to develop a model which combines chloride ingress and loading action to predict the chloride penetration and the initial corrosion time of concrete structures in the marine environment This model will be based on theories and experiments of chloride diffusion test, chloride content tests and flexural cyclic loading test 1.2 The objective of study In this study, main objectives are considered . / CHLORIDE PENETRATION / CONCRETE / FLEXURAL CYCLIC LOAD / TIDAL ENVIRONMENT MIEN VAN TRAN: MODELING OF CHLORIDE PENETRATION INTO CONCRETE STRUCTURES UNDER FLEXURAL CYCLIC LOAD AND TIDAL ENVIRONMENT. . Prediction of chloride profiles of concretes subjected to cyclic load and 5 year exposure to tidal environment, w/c=0.4 89 Figure 4.14 Prediction of chloride profiles of concretes subjected to cyclic. period of concrete structures under combination of cyclic loading and tidal environment. 2. Do the experimental flexural cyclic loading of concrete structures in the simulated marine environment

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  • Coverthai-1

  • Cover1

  • Cover2

  • Coverthai-3

  • Cover3

  • Cover4

  • Table of content

  • Cover6

  • Cover7

  • Chapter I

  • Chapter II

    • 2.5 Concluding remarks

    • Chapter III

      • 3.1.1 Testing procedures of chloride content

      • 3.1.2 Testing procedures of XRD Rietveld and EPMA

      • Chapter IV

        • Table 4.1 Designed mechanical and physical properties of concrete

        • Chapter V

          • Table 5.1 Mixture proportions used in research

          • 5.1.1 Testing procedures of chloride diffusion coefficient

          • 5.1.2 Testing procedures of chloride content

          • 5.1.3 Testing procedures of flexural strength and flexural cyclic load in tidal zone

          • Regarding to the test of flexural cyclic load in tidal zone, concrete beams are both subjected to flexural cyclic load and simulated tidal zone, which include 12 hour wetting in NaCl 10% solution and 12 hour drying in atmosphere, see Figure 5.4. This kind of testing is used to verify the proposed model of chloride penetration into concrete under cyclic load and tidal effect. In this test, 400mm long, 100mm thick, and 100mm wide beams are cast with OPC concrete, w/c = 0.5. After curing for 60 days in water, the beams where all surfaces, except the bottom face, are covered by epoxy subjected to flexural cyclic loads with low frequency, 0.01Hz, for SR values of 0.5; 0.6; 0.7; and 0.8 up to N1 cycles. Simultaneously, the simulated tidal conditions are applied to concrete beams so that the concrete beams are subjected to condition resembling the couple of loading and a tidal environment. After finishing N1 cycles of flexural cyclic load, cored concrete specimens at the middle bottom of beams are used to analyze total chloride contents at different depths.

          • Chloride diffusion tests include both short-term and Long-term chloride diffusion. These tests are conducted following testing procedures mentioned in section 5.1. Results of the chloride diffusion coefficients are shown in Table 5.2, 5.3 and Figure 5.5. In Table 5.2 and 5.3, one can see that values of chloride diffusion coefficient as well as surface chloride content increase when w/c increases because more pores and diffusing paths may form as w/c increases. This trend is observed both in the short-term and long-term test.

            • Table 5.3 Diffusion coefficient values given by long-term test, concrete cured at 28 days

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