Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Tomoyuki Koyama Last modified date:2019.06.18

Associate Professor / Structural Engineering and Disaster Mitigation Section / Department of Architecture and Urban Design / Faculty of Human-Environment Studies


Papers
1. Bokyeong Lee, Gyuyong Kim, Jeongsoo Nam, Kyehyouk Lee, Gyeongtae Kim, Sangkyu Lee, Kyoungsu Shin and Tomoyuki Koyama, Influence of α-Calcium Sulfate Hemihydrate on Setting, Compressive Strength, and Shrinkage Strain of Cement Mortar, Materials, 59-66, 12,163 pp.1-13, 2019.01.
2. Investigation of Frost Damage of Concrete Structures in Kyushu
Part 1 Results of Appearance Research.
3. EFFECT OF AMINE-BASED STRENGTH ENHANCER ON EARLY STRENGTH IMPROVEMENT USING FLY ASH.
4. Sangchul SHIN, Tomoyuki Koyama, Korekiyo ITO, A STUDY ON THE MOCK-UP TEST FOR QUALITY CONTROL OF FLOOR SLAB CONCRETE ACCORDING TO CURING METHOD UNDER HOT WEATHER, The 7th International Conference of Asian Concrete Federation, 2016.11, This study was conducted to investigate the initial water movement and the hydration property of poured concrete under a hot weather environment and examined impacts from the curing method (water curing, sheet curing and membrane curing), start time and period of curing to the strength and durability of hardened concrete. The floor slab specimens produced in the size of 800 × 800 × 200 mm to consider real construction site. The results of this mock-up test indicate that the bleeding is finished after 3.5 hours, the concrete surface becomes dried state rapidly, and the hydration reaction was very fast in the hot weather condition. Curing is effective if it is started from the point of bleeding ending and start of surface drying. For curing method, the water curing is most effective. If the water curing is complicated, the quality control though the sheet curing or the membrane curing is available..
5. Study on Compressive Strength of Concrete mixed with Various Types of Powder at Constant Cement Contents by Taking Account of Pore Structure.
6. Sun Yuping, Tomoyuki Koyama, Takeuchi Takashi, Seismic Performance and Evaluation of Fly-Ash Concrete Columns – Towards resilient and sustainable concrete structures, SCMT3(The 3rd International Conference on Sustainable Construction Materials and Technologies), e.251, 2013.08.
7. A study of strength improvement of mortar using for flyash concrete additives under various temperatures.
8. Study on Long Term Properties of Concrete with High Strength Artificial Aggregate.
9. Relationship between Compressive Strength and Dynamic Modulus of Elasticity in the Cement Based Solid Product for Consolidating Disposal of Medium-Low Level Radioactive Waste.
10. Estimation on Applied Period of Hot Weather Concreting under Global Warming.
11. Durability of Concrete Containing Large Quantity of Fly Ash with Constant Cement Content
―Long Term Exposure Test on Weak Sulfuric Acid Environment―
, Journal of Architecture and Urban Design, Kyushu University, No.21, pp.41-47, June, 2012
Long term exposure tests on sulfuric acid resistance of concrete containing a large quantity of fly ash with constant cement content were carried out under weak acid environment, i.e., in the atmosphere and soil which has a pH value between 4 and 5. In six years’ exposure tests, the following results were obtained.
a) Specimens embedded in the acid soil expanded slightly, but cracking was not observed on the surfaces of the specimens. b) In specimens with no fly ash content (Portland cement only) or with low fly ash content, those surface parts were dissolved severely by sulfuric acid. Nevertheless, dynamic modulus of elasticity of these specimens was unimpaired. c) It was confirmed that with an increase in the fly ash content, the resistance of concrete to sulfuric acid improved, in other words, dissolution and discoloration of the surface parts hardly occurred..
12. Study on Quality Control in Hot Weather Concreting
―Experiment on Real Size Column and Wall Specimens―,
Journal of Architecture and Urban Design, Kyushu University, No.18, pp.61-68, July, 2011
This study was carried out with the aim of investigating the influence that the high temperature of ready mixed concrete as delivered and the time for formwork to remain in place exerted on the correction value of concrete strength and the carbonation ratio of the concrete on hot weather concreting. The specimens in the experiments were placed at 35℃ and 38℃ of the temperature of concrete as delivered. The times for formwork to remain in place of the specimen were from 1 day to 28 days. This paper describes that the appropriate correction value of concrete strength is 6N/mm2 on hot weather concreting and the time for formwork to remain in place shall be 5 days or longer from the view of the durability if the temperature of concrete as delivered exceeds 35℃..
13. Tomoyuki Koyama,Yasunori Matsufuji,Shizuo Harada,Toshio Yonezawa,Kyoichi Tanaka,Etsutaka Maeda and Fumio Oshida, DETERIORATION PROCESS OF CONCRETE IN WEAK SULFURIC ACID SOIL, 2nd International Symposium on Service Life Design for Infrastructure 2010, 1, 213-220, 2010.10.
14. Toshio Yonezawa, Yasunori Matsufuji, Shizuo Harada, Tomoyuki Koyama, Etsutaka Maeda, Kyoichi Tanaka and Fumio Oshida , NEUTRALISATION OF CONCRETE UNDER WEAK SULFURIC ACID ENVIRONMENT, 2nd International Symposium on Service Life Design for Infrastructure 2010, 1, 99-106, 2010.10.
15. Estimations for Strength Expression of Concrete Containing Mineral Admixture of Powder with Constant Cement Content, Journal of Architecture and Urban Design, Kyushu University, No.18, pp.61-68, July, 2010.
16. A SURVEY ON PHYSICAL FUNCTIONS OF CONSTRUCTION WORKERS.
17. Neutralization of Concrete under Weak Sulfuric Acid Environment.
18. Evaluation of Carbonation for Concrete Containing Large Quantity of Fly Ash.
19. The Equation Estimating Temperature of Hot Weather Concrete
―Real Size Experiments on Coefficient α and β in the Equation―.
20. 小山智幸,孫玉平,藤永隆,小山田英弘,緒方太, Mechanical Properties of Concrete Beam Made of a Large Amount of Fine Fly Ash, Proceedings of the 14th World Conference on Earthquake Engineering, 8pages(CD-ROM), 2008.10.
21. VERIFICATION OF PERFORMANCE ON CONCRETE CONTAINING LARGE QUANTITY OF FLY ASH WITH FULL SCALE SPECIMENS.
22. Minimum Curing Period on Hot Weather Concreting
—Effect of Deteriorated Layer on Compressive Strength—.
23. STUDY ON QUALITY CONTROL OF MASS CONCRETE IN IMPORTANT STRUCTURES : Results of monitoring tests related to durability and effect of coatings up to 20 years
.
24. Yasufumi Mitarai, Takeshi Ohike, Masahiro Moriya, Takanori Ogata and Tomoyuki Koyama, Long-term Study on Properties of High-strength Mass Concrete in PCCV
(Prestressed Concrete Containment Vessel)
(Monitoring Test Results and Durability of Concrete over 22 years), Transactions, SMiRT (STRUCTURAL MECHANICS in REACTOR TECHNOLOGY) 19, Toronto, August 2007 , H03/5-1〜8(CDROM), 2007.08.
25. Carbonation of Concrete using Fly Ash by Long-term Exposure Test.
26. INVESTIGATION ON CONCRETES AND STEELS USED AT COAL MINING STATION "SHIME" AS INDUSTRIAL HERITAGE.
27. Flowability Improvement of Concrete Containing Inorganic By-product Slurry
Effect of Zeta Potential in Slurry on Flowability of Concrete.
28. Degradation Model of Concrete Exposed in Weak Sulfuric Acidity Soil.
29. Strength Development of Concrete Containing Large Quantity of Inorganic By-product Powders.
30. Mohd. Faris Khamidi, Yasunori Matsufuji, Kentaro Yamaguchi, Adapting Dry-masonry Brick House System as a Green Cycle Model for Asian Markets, Proceedings of Conference on Use of the Recycled Materials in Building and Structures (PRO 40), Volume 1 RILEM 2004, pp.183-192, 2004.11.
31. Static Characteristics of Construction Tiding over Vibration - Evaluation for the Bending Strength of SRB-DUP Beam -.
32. Static Characteristics of Construction Tiding over Vibration - Evaluation for the Shear Strength of SRB-DUP Wall -.
33. Maximization of Coal Ash Content into Concrete.
34. Study on Occupational Safety and Health Management for Construction Industry - Analysis of the Influences of Working Environment -.
35. Y.Koshiro, T.Oike, T.Kawaguchi, T.Koyama, Y.Matsufuji, DEVELOPMENT OF SELF-COMPACTING CONCRETE CORRESPONDING TO THE SPECIFIED STRENGTH FOR CFT, 28th Conference on OUR WORLD IN CONCRETE & STRUCTURES, pp.357-364, 2003.08.
36. Basic Study on Evaluation Method for Discontinuous Joint of Concrete.
37. Y. Matsufuji, T. Koyama, etc., Development of Stabilization System of Coal Ash to Use Large Quantity into Concrete, ANNUAL REPORT of the Faculty of Engineering Kyushu University 2002, pp.94-95, 2003.05.
38. Y. Matsufuji, T. Koyama, etc., Habitat System to Maximize Throughput for Sustainable Development, ANNUAL REPORT of the Faculty of Engineering Kyushu University 2002, pp.88-93, 2003.05.
39. Study on Occupational Safety and Health Management for Construction Industry - Analysis of the Accident Occurrence Rates based on Age of Workers -, Journal of Architecture and Urban Design, Kyushu University, No.3, pp.141-148.
40. Architecture for Sustainable Development, Journal of Architecture and Urban Design, Kyushu University, No.3, pp.1-15.
41. Mix proportion theory of strength controlling concrete containing large quantity of coal ash, JOURNAL OF THE SOCIETY OF MATERIALS SCIENCE, JAPAN, Vol.51, No.10, pp.1111-1116.
42. Study on the Development of a Coal Ash Utilization System, Advanced Clean Coal Technology International Symposium 2002, E3.2-1〜20.
43. Treatment System of Coal Ash to Reduce Environmental Load for Sustainable Thermal Power Generation, Journal of Architecture and Urban Design, Kyushu University, No.2, pp.57-68.
44. Treatment System of Coal Ash to Reduce Environmental Load for Sustainable Thermal Power Generation, Journal of Architecture and Urban Design, Kyushu University, No.2, pp.57-68.
45. Y.Matsufuji,T.Koyama,K.Funamoto and K.Ito, Mix Proportion Principle of Concrete Containing Large Quantity of Coal Ash with Constant Cement Content, TRANSACTIONS OF JAPAN CONCRETE INSTITUTE, Vol.23, pp.97-110, 2002.02.
46. Study on Evaluation and Prevention of Discontinuity Joint of Concrete Part 1 Decline of Strength and Evaluating Method of the Defect, Technology Reports of Kyushu University, Vol.74, No.5, pp.587-593.
47. Labor Accident on Hot Weather Ambience, Journal of Architecture and Urban Design, Kyushu University, No.1, pp.127-135.
48. Study on Occupational Health and Safety Management for Construction Industry - Relation between Incidence of Accidents and Construction Period - , Technology Reports of Kyushu University, Vol.74, No.3.
49. Study on Occupational Health and Safety Management for Construction Industry - An Analysis of Fall Accidents in Building Construction Sites -, Technology Reports of Kyushu University, Vol.74, No.3, pp.237-242.
50. Study on Occupational Health and Safety Management for Construction Industry - Outline of the Occupational Accidents in Construction Industry -, Technology Reports of Kyushu University, Vol.74, No.3, pp.231-236.
51. Mix Proportion Principle of Concrete Containing Large Quantity of Coal Ash with Constant Cement Content, CONCRETE RESEARCH AND TECHNOLOGY Japan Concrete Institute, Vol.12, No.2 (Issue 26), pp.51-60.
52. Study on Distribution Function of Quality Control Data including Human Bias, Technology Reports of Kyushu University, Vol.74, No.2, pp.123-130.
53. Stubilization Treatment of Coal Ash for Large Quantity Use to Concrete, THE CENTER OF ADVANCED INSTRUMENTAL ANALYSIS KYUSHU UNIVERSITY, No.18(2000), pp.37-41.
54. Hidehiro KOYAMADA, Yasunori MATSUFUJI, Tomoyuki KOYAMA and Rui AKAMATSU, AN EXPERIMENTAL STUDY ON THE MIX DESIGN OF MEDIUM-FLUIDITY CONCRETE, TRANSACTIONS OF THE JAPAN CONCRETE INSTITUTE, Vol.22, pp.21-26, 2001.02.
55. Setting Up of Construction System for Housing Procurement Management System by Builder as Agent, Technology Reports of Kyushu University, Vol.74, No.1, pp.47-54.
56. FORMULATION OF TENSILE STRAIN AT CRACKING OF GREEN CONCRETE, JOURNAL OF STRUCTURAL AND CONSTRUCTION ENGINEERING (Transactions of AIJ), No.538, pp.29-34.
57. Experimental Study on Mix Proportion Method of Middle Fluidity Concrete, Proceedings of the Japan Concrete Institute, Vol.22, No.2, pp.463-468.
58. Stabilization Treatment for Large Quantity Use of Coal Ash to Concrete, Proceedings of the Japan Concrete Institute, Vol.22, No.2, pp.115-120.
59. Compressive Strength and Neutralization of Concrete Containing Large Quantity of Coal Ash, Proceedings of the Japan Concrete Institute, Vol.22, No.2, pp.97-102.
60. Out-door Expose Test of Concrete with Fly Ash, Proceedings of the Japan Concrete Institute, Vol.22, No.2, pp.85-90.
61. Physical Properties of High Quality Concrete Exposed to Sulfuric Acid Soil for Seven Years, Proceedings of the Japan Concrete Institute, Vol.22, No.1, pp.247-252.
62. EXPERIMENTAL STUDY ON PROPERTIES OF FLY-ASH CONCRETE IN HOT WEATHER, JOURNAL OF STRUCTURAL AND CONSTRUCTION ENGINEERING (Transactions of AIJ), No.531,pp.1-6.
63. EXPERIMENTAL STUDY ON MEASURES OF STIFFENED ZONE IN GREEN CONCRETE, Cement Science and Concrete Technology, No.53, pp.941-946.
64. EXPERIMENTAL STUDY ON CORRELATION BETWEEN DISTRIBUTION OF REBOUND NUMBER IN DEPTH AND MECHANICAL PROPERTIES, Cement Science and Concrete Technology, No.53, pp.805-810.
65. CARBONATION BEHAVIOR OF CONCRETE CONTAINING LARGE QUANTITY OF COAL ASH, Cement Science and Concrete Technology, No.53, pp.779-784.
66. Mix Proportion Principle of Concrete Containing Large Quantity of Fly ash, Technology Reports of Kyushu University, Vol.72, No.6, pp.703-710.
67. Physical Properties of High Quality Concrete Exposed to Sulfuric Acid Soil for Five Years, Proceedings of the Japan Concrete Institute, Vol.21, No.2, pp.883-888.
68. Study on Properties at Early Ages of Concrete Substituting Fly Ash for Cement less than 40% (in Weight), Proceedings of the Japan Concrete Institute, Vol.21, No.2, pp.103-108.
69. Linear Analysis Model for Evaluation of Construction Management System, Technology Reports of Kyushu University, Vol.72, No.2, pp.169-175.
70. Experimental study on distribution of rebound number in depth of hardened concrete, JCA PROCEEDINGS OF CEMENT & CONCRETE, No.52, pp.1012-1017.
71. Experimental study on conditions of stiffening zone in green concrete, JCA PROCEEDINGS OF CEMENT & CONCRETE, No.52, pp.1006-1011.
72. Properties at early age of concrete containing large quantity of coal ash, JCA PROCEEDINGS OF CEMENT & CONCRETE, No.52, pp.922-927.