Influence of silicate modified expansion agent on engineering performance of ultra-high-strength concrete = 규산염 개질 팽창제가 초고강도 콘크리트의 공학적 성능에 미치는 영향

다국어 초록 (Multilingual Abstract)

At an early age, ultra-high-strength concrete (UHSC) exhibits a large autogenous shrinkage, which easily leads to matrix shrinkage and cracking. This poses a significant threat to the service life of a building structure. In this study, the effects of silicate modified expansive agents (SMEAs) on the engineering performance of UHSC were systematically investigated. The compressive strength, ultrasonic pulse velocity, and surface resistivity were determined. Moreover, Heat of hydration, TG, Fourier transform infrared spectroscopy (FTIR) and other microscopic analyses were used to characterize the chemical composition of the UHSC. It can be seen from the test results that the compressive strength of UHSC tends to decrease with the increase of SMEA addition. The results of TG, X-ray diffraction, and other microscopic analyses indicated that the main composition of the UHSC was a mixture of calcium (aluminate) silicate hydrate, calcium hydroxide, and ettringite.

목차 (Table of Contents)

• Abstract Ⅰ
• Keywords Ⅱ
• CONYENTS Ⅲ
• List of Figures Ⅵ
• List of Tables Ⅶ
• I. Introduction 1
• 1.1 Research background 1
• 1.2 Expansion agent 2
• 1.3 Outline of the thesis 4
• II. Literature Review 5
• 2.1 UHSC 5
• 2.2 Silicate Modified Expansive Agents (SMEA) 6
• 2.3 Inadequate previous research and the necessity of this study 7
• III. Materials, UHSC design, and Test methods 8
• 3.1 Materials 8
• 3.2 UHSC design 11
• 3.3 Test methods 12
• 3.3.1 Fluidity 12
• 3.3.2 Compressive strength 13
• 3.3.3 Heat of hydration 14
• 3.3.4 XRD 15
• 3.3.5 Inductively coupled plasma-optical emission spectrometer (ICP-OES) 16
• 3.3.6 TG 17
• 3.3.7 Fourier transform infrared spectroscopy (FTIR) 18
• IV. Results and discussion 19
• 4.1 Fluidity 19
• 4.2 Compressive strength 20
• 4.3 Heat of hydration 22
• 4.4 XRD 24
• 4.5 ICP-OES 26
• 4.6 TG 27
• 4.7 FTIR 29
• 4.8 Discussion 31
• 4.8.1 Effects of SMEA on UHSC Hydration Products 31
• V. Conclusions 32
• Acknowledgement 34
• References 35
• 국문 37