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Recently, the development of the recycled resource is active in the background of effective use of the resource and the depletion of the final disposal dump, etc. Especially, the development of the technology used for the pavement of those recycled resources is active. Using these recycled resources comes to recycle certainly. However, whether it has contributed to the environmental load decrease in total until abandoning since using these manufactures it is not clarified. Then, the resource consumption, the saving resource, and the environmental load when using it for pavement were provisionally calculated for scrap tire and waste plastics, and LCA evaluation was examined. As a result, it was shown overall might decrease the environmental load though the recycled resource pavement might partially increase the load.

In Japan, several mix design methods for the recycled porous asphalt are being developed and proposed. These methods include the one to use Cantabro test and the one by the extraction recovery of asphalt. However, they have not been established yet, because they have some problems. The authors studied the mix design method using asphalt mortar, the new method evaluating several properties without extraction. As a result, the new mortar method was a method of not only appreciable of servicing temperature but also appreciable of constructing temperature. In addition, the labor of the method was also light.

In this research, to establish the method of recycling porous asphalt mixture, the propriety of two mixing design methods being proposed was examined. The result is shown below. 1) The problem was found in the deciding method of the amount of rejuvenators of recycled porous asphalt mixture and the deciding method of optimal asphalt content 2) It has been understood might not obtain satisfactory properties about mixture properties not so examined when mixing is designed. 3) It has been understood that there is a possibility to be improved from present methods by adding easy tests.

Polymer-modified asphalt binder is applied for the heavy trafficked pavement because the asphalt is superior in terms of plastic flow and abrasion resistance. Recently, the development of warm-mix polymer modified asphalt has proceeded. Then, it is necessary to evaluate the characteristics of these asphalt binders. In general, the authors have estimated the physical behavior of polymer-modified asphalt by DSR test. However, it seems to difficult for DSR test to estimate the nonlinear viscoelastic behavior such as warm-mix polymer-modified asphalt. In this study, the authors validated the availability of MSCR test for the characteristics of the widely distributed warm-mix polymer-modified asphalts. ポリマー改質アスファルトバインダは塑性変形抵抗性や摩耗抵抗性、はく離抵抗性等に優れており，重交通路を中心に普及している．近年では，CO₂排出量削減や作業環境改善策として中温化ポリマー改質アスファルトバインダの開発も進んでおり，既に複数メーカーから市販されている．一般的に，アスファルトバインダの物理性状はDSR試験から得られるパラメータによって評価されてきたが，改質アスファルトバインダの非線形粘弾性状を適切に評価できないことが指摘されている．本研究では，国内で流通している複数の中温化ポリマー改質アスファルトバインダの性状を調査し，基本性状の相違を明らかにするとともに，物理性状評価に対して繰り返しクリープ試験(MSCR試験)の有効性を検証したので報告する．

Hexavalent chromium is sometimes eluted from cement concrete recycled base course material. Therefore, hexavalent chromium eluted restraint technology is developed. The concentration analysis of hexavalent chromium is difficult, when a reducer coexists. There were not that standard measurement methods. The authors have already developed the analysis method of hexavalent chromium when a return substance coexists. When using this way, even if there is a return substance, hexavalent chromium is measured right. So hexavalent chromium reduction technologies were studied using accessible materials. As a result, hexavalent chromium eluted restraint technologyreducing sugar has been developed. セメントコンクリート再生路盤材からは六価クロムが溶出する可能性があるため，溶出の確認が行われるようになっている．これに伴い，六価クロム溶出低減技術も開発されるようになっているが，還元物質を用いる対策の場合，JISの分析法を用いることができず，評価が難しいのが現状である．本研究では，独自に開発した還元物質共存下でも容易に六価クロムを分析できる方法を用いて，自然由来の物質や入手が容易な物質の中から，還元効果が期待できる物質を選定し，六価クロムの溶出低減効果を検討した．その結果，比較的入手が容易な一部の果汁や還元糖の中に六価クロム溶出低減効果が高いものがあることを把握した．

The warm-mix asphalt technics have been applied to the hot asphalt pavements to improve the quality of constructions and to reduce CO₂ emission. Although many studies have reported that the warm-mix additives affected the physical characteristics of asphalt mixtures, the basic characteristics of the warm-mix asphalt binder has not been revealed. In this investigation, the authors measure the differential scanning calorimetry (DSC) and the viscoelastic property of the warm-mix asphalt binder in a wide range of temperature. Also, they discuss the validity of the thermal analysis to detect the physical change of the asphalt binder. 施工性改善やCO₂排出削減などを目的として，加熱アスファルト舗装に対する中温化技術の開発や利用が進んでいる．これまで，中温化剤の添加によるアスファルト混合物の物理的性状の変化は多く報告されているが，アスファルトバインダの基礎的な物理性状については十分な言及がなされていない．本研究では，中温化剤によるアスファルトバインダの性状変化を把握することを目的として，示差走査熱量測定によりアスファルトや中温化剤の広範囲の温度域での熱特性や，これに対応した粘弾性状を調べた．さらに，熱特性と粘弾性状の関係について検討した．