報告書番号

383027

タイトル（和文）

１００度を超える高温下におけるコンクリートの強度性状－圧縮強度特性と鉄筋の機械的性質－

タイトル（英文）

STRENGTH AND ELASTIC PROPERTIES OF CONCRETE AND REINFORCING BARS IN THE TEMPERATURE RANGE

概要 （図表や脚注は「報告書全文」に掲載しております）

現在我国で開発研究が進められている高速増殖炉では，熱交換媒体として金属ナトリウムが３５０℃～５００℃で用いられるため，軽水炉の場合と比較して，コンクリート製の構造物に与えられる温度条件は相当厳しくなることが予想される。１００℃を超える温度条件，特に２００℃～５００℃の温度条件では，コンクリートおよび鉄筋の材料物性のデータはあまり得られておらず，その集積が急がれている。本報告は，コンクリートおよび鉄筋の材料物性の温度依存性を把握するため，常温～５００℃の温度条件下でコンクリートの圧縮，割裂，曲げの各試験および鉄筋の引張試験を行い，これらの結果を取りまとめたものである。コンクリートの材料物性の温度依存性は，使用骨材の種類により影響を受けるが，得られた結果は一般的に認められている性状と定性的には一致したものであった。

概要 （英文）

STRENGTH TESTS OF CONCRETE AND REINFORCEMENTS AS WELL AS FLEXURAL TESTS OF RC MEMBERS IN THE TEMPERATURE RANGE FROMNORMAL UP TO 500 DEGREES CENTIGRADE HAVE BEEN CONDUCTED IN CIVIL ENGINEERING LABORATORY OF CRIEPI. THE EXPERIMENTAL RESULTS CONCERNING COMPRESSIVE STRENGTH PROPERTIES OF CONCRETEAS WELL AS TENSILE MECHANICAL PROPERTIES OF REINFORCING BARS ARE DESCRIBED IN THIS PAPER. MAIN CONCLUSIONS OBTAINED FROM THESE EXPERIMENTS WERE AS FOLLOWS. 1 COMPRESSIVE PROPERTIES OF CONCRETE AFTER HEATING. (1)COMPRESSIVE STRENGTHS OF CONCRETE EXPOSED TO ELEVATED TEMPERATURES FROM 100 DEGREES CENTIGRADE TO 200 DEGREES CENTIGRADE WERE 1.1 OR 1.2 TIMES AS LARGE AS THOSE OBTAINED AT NORMAL TEMPERATURE.HOWEVER,IN THE TEMPERATURE RANGE EXCEEDING 200 DEGREES CENTIGRADE COMPRESSIVE STRENGTH REDUCED REMARKABLY DEPENDING ON THE AMOUNT OF THE TEMPERATURE RISE MAINLY DUE TO THE DETERIORATION OF BOND BETWEEN CEMENT PASTE AND AGGREGATES. (2)CYCLIC HEATING AND COOLING INFLUENCED THE DEGREE OF REDUCTION IN COMPRESSIVE STRENGTH OF CONCRETE TO A LARGE EXTENT COMPARED WITH THE SPECIMENS SUBJECTED TO THE SUSTAINED ELEVATED TEMPERATURES. THE INFLUENCES OF TEMPERATURE HYSTERESISES ON THE REDUCTION OF COMPRESSIVE STRENGTH BECAME NEGLIGIBLE AFTER HEATING FORTEEN DAYS AND AFTER TEN CYCLES OF TEMPERATURE REVERSALS. 2 TENSILE PROPERTIES OF REINFORCEMENTS (1)THE TEMPERATURE DEPENDENCE OF YIELD POINTS,TENSILE STRENGTHS,ELONGATIONS AND CONTRACTIONS OF CROSS AREA SHOWED ALMOST THE SAME TENDENCIES AS THOSE OF SEMI-KILLED STEEL SO FAR CONFIRMED IN THE FOREGOING TESTS. (2)REFERRING ALSO TO THE EXISTING TEST DATA,THE YOUNG S MODULUS OF REINFORCEMENT IS INCLINED TO DECREASE GRADUALLY ACCORDING TO TEMPERATURE RISE.

報告者

キーワード