PURPOSES : In this study, the alkali aggregate reactivity and expansion characteristics of mortar mixed with waste glass (a recycled aggregate) were confirmed to verify the alkali-silica reaction (ASR) stability and review the appropriateness of the alkali aggregate reactivity test method following the replacement of recycled aggregate. METHODS : The alkali-aggregate reactivity of waste glass aggregates was measured using the chemical and physical methods described in KS F 2545 and ASTM C 1260, respectively. The reactivity was classified by comparing the results. Cement with a high-alkali content was used to simulate an environment that can induce ASR. Non-reactive fine aggregates, waste glass fine aggregates, reactive general aggregates, and Ferronickel slag aggregates were used as control groups. RESULTS : Waste glass fine aggregates were classified as reactive when applying the chemical method. In the physical method, they were classified as reactive at 100% and latent reactive at 1%, based on the mixing ratio. Additionally, we discovered that the reliability of the chemical method was low since the ASR of the aggregates was classified differently based on the evaluation method, while the results of the chemical and physical test methods were inconsistent. CONCLUSIONS : To determine the alkali reactivity of recycled aggregates, the complex use of chemical and physical methods and analysis based on the mixing ratio of the reactive aggregates are required. Small amounts of waste glass aggregate replacements affected the ASR. Because ASR reaction products can affect the long-term thermal expansion of the structure, further research is needed to use ASR aggregates in structures.

본 연구는 2005~2007년까지 3년에 걸쳐 폐광산 수계 의 유출수에 의해 직접적으로 영향 받는 하천 및 대조군 (Control, Co) 하천에서 이∙화학적 수질특성, 수질 내성 도 및 트로픽 길드 특성, 다변수 생태모형(Multimetric Health Model)을 이용한 생태 건강도 평가 및 물리적 건 강도 평가 모형(QHEI model)을 이용한 생물 서식지 평 가를 실시하였다. 또한, 폐광산의 유출수에 대한 생태독 성 평가를 위해 버들치(Rhynchocypris oxycephalus)를 이용하여 현장 Enclosure 노출시험(In situ Enclosure Bioassay) 을 실시하였고, 해부학적 장기 조직의 평가지수 모 형(Necropy-based Health Assessment Index, Nb-HAI)을 이용하여 대조군(Co)과 처리군(T)의 광산폐수의 영향을 평가하였다. 이들에 대한 장기 조직의 영향평가는 각 Enclosure에 10 개체씩 투입하여 지라(Spleen), 신장(Kidney), 아가미(Gill), 간(Liver), 눈(Eyes), 지느러미(Fins) 의 조직분석(Tissue analysis)을 실시하였다. 대조군과의 비교평가에 따르면, 폐광산의 유출수는 하천수를 pH 3.2 까지 떨어뜨려 강한 산성폐수와 유사한 특성을 보였고, 급격한 수소이온 증가 및 총용존물질(Total Dissolved Solid, TDS)의 증가를 가져왔다. 서식지 평가의 QHEI 모 델 값은 지점별 유의한 차이(p¤0.05)를 보이지 않은 반 면, 다변수 생태모형(Multimetric Health Model)을 이용 한 생태 건강도는 3년 동안 대조군(Co)에서 Mm-EH 모델 값은 16~20, 처리군(Mw)에서는 0으로 폐광 유출수의 영 향을 받는 지점에서는 “악화상태(P)”로 나타났다. 또한, Enclosure 노출평가 따르면, Nb-HAI 모델값은 3년 기간 동안 대조군에서 0~3으로 나타나 “최적~양호상태” (Ex~ G)로 나타난 반면, 폐광 유출수의 Enclosure에 포함된 처 리군(Treatment)에서 모델값은 모두 100 이상(범위: 100 ~137)을 상회하여 “악화상태(P)”로 평가되었으며, 크게 손상된 장기조직은 간(Liver), 신장(Kidney), 아가미(Gill) 로 나타나 향후 폐광산 유출지역의 수질 및 생태관리가 시급한 것으로 사료되었다.

In an attempt of develop composite flours, D. aimadoimo of yams in Korea was investigated with respect to its physicochemical properties and sensory analysis with baking bread. The results are summerized as follows ; 1. Yam had 73.21% of water, 21.65% of carbohydrate, 3.3% of crude protein, 0.25% of fat, 1.60% ash and 20.3% of starch. 2. Sucrose was 78% of the total free sugars in yam flour. It was contained which 67% of total free amino acids were serine, arginine & alanine and 23.6% of total amino acids was glutamic acid. 3. As the yam flour level in amylogram patterns (8% dry basis) was increased, the initial pasting temperature was increased and the viscosity decreased. 4. Replacement of yam flour with 10% wheat flour was the best in sensory evaluation of the products.