In this paper, investigate the effect of the quality of fresh UHPC on the mixer type, it was found that the use of twin shaft mixer was fine. On the other hand, pan type mixer is required for adjustment mix proportion.

In this paper, evaluated on the effect of high temperature history on the resistance to freeze-thaw of concrete. As a result, The concrete subjected to high temperature history at 50℃ and 70℃ showed good of the resistance to freezing and thawing.

This paper reviewed on the minimum strength of concrete in cold climates from the viewpoint of durability. The results show that the minimum strength to prevent early frost damage recommend to 21 MPa.

This research The main focus of this research is to provide basic data for concrete recreation planning of future site by selecting Gwangmyeong-Siheung housing district, large residential development district focused on rural areas, by evaluation of recreation value and detailed biotope type classification. The main results of analysis are as follows. As a result of basic survey of the research area, total 79 family and 307 taxonomic groups are identified and also naturalization index and urbanization index were estimated 16.6 % and 17.6% respectively. Also, as a result of biotope type classification, it is divide into 12 biotope type gorups including forest biotope type group and its subordinate 53 biotop types. As a result of first value evaluation, there are total 13 biotope types such as vegetation-full artificial rivers in I grade. In addition it is analyzed as 9 types of II grade, 5 types of III grade, 8 types of IV grade, 18 types of V grade. Lastly, as a result of second evauation, it is analyzed that there are 21 special meaningful areas for recreation and natural experience(1a, 1b), and 50 meaningful areas for recreation and natural experience(2a, 2b, 2c). It is regarded that the results of biotope types classification and recreation value from this research play roles of analyzing the Suitable site for recreation area before development in terms of large residential development district, and then these results provide important basic data to secure recreational and natural experience area in development planning.