This paper verifies the difference of the seismic behavior and seismic damage of the neighboring two reinforced concrete piers damaged by the 1995 Hyogoken Nanbu earthquake. The two piers were almost the same size, carrying slightly different dead load, and were provided with the same reinforcement arrangement except the amount of longitudinal reinforcement at the bottom portion of the piers. The pier with more reinforcement was completely collapsed due to this near field earthquake by shear failure at the longitudinal reinforcement cut-off while the other was only damaged at the bottom by flexure even though the longitudinal reinforcement cut-off was also existed at the mid height of the pier. According to the results of the pseudo dynamic test, the seismic damage was recognized to be greatly dependent on the ground motion characteristics even though the employed ground motions had the same peak acceleration. The severe damage was observed when the test employed the seismic wave that had strong influence to the longer period range compared to the initial natural period of the pier. On the other hand, based on the similar model experiment, the defect of gas-pressure welded splice of longitudinal reinforcement was revealed to save the piers against collapse due to the so-called fail-safe mechanism contrary to the intuitive opinion of some researchers. It was concluded that the primary cause of the collapse of the pier was the extremely strong intensity and peculiar characteristics of the earthquake motion according to both the site-specific and the structure-specific effects.

The control performance of LCVA designed for mitigation of wind-induced motion of Songdo high rise building is evaluated using 1/20 scaled test model. The effectiveness of the LCVA is then examined tuning LCVA to 90%, 100%, and 110% of the natural frequency, 0.74Hz. The test structure is excited using a sinusoidal signal ranging 0.2 ~ 1.2 Hz with 5.5mm displacement, and acceleration and displacement of structure, water height, and shear force are measured. Experimental results indicate that the LCVA tuned to 100% of the natural frequency with orifice opening ratio of zero reduce the peak and RMS displacement up to 67% and 72%.

본 총설에서는 전기투석 공정의 운전과 설계 능력 향상을 위해 이온교환막의 막오염현상에 관한 연구를 조사하였다. 이온교환막의 막오염현상을 정량적으로 평가하기 위해 압력차를 구동력으로 하는 막공정의 막오염지수와 유사한 전기투석 막오염지수(EDMFI)를 정의하였다. 막오염현상은 무기오염원인 실리카졸과 유기 오염원인 휴믹산과 BSA를 함유한 전기 투석 실험 결과를 비교하여 연구되었다. 이 비교에서 EDMFI는 전기투석 공정의 막오염경향을 정량적인 척도로 유용하게 이용될 수 있음을 보여주었다. 새로운 오염저감 기술로 사각파 전원이 유효함이 유기 오염물을 포함한 전기투석 실험결과에서 보고되었다. 이펄스 형태의 사각파 전원은 최적주파수에서 막오염현상을 현저하게 감소시킬 수 있었다.

In view of the rapid development of economics and technology, perilous meteorological and geological conditions often cause natural disasters and result in severe loss of lives and properties in Taiwan. To promote multi-hazard mitigation strategies in an integrated a, pp.oach, the National Science Council established a National Science and Technology Program for Disaster Mitigation in January 1998. This program emphasizes on the implementation of research results in the National Disaster Management System. This paper describes the earthquake loss estimation methodology that is currently developed in Taiwan. Topics of potential earth science hazards (PESH) and building vulnerability analysis are described in detail.

Korea is not considered to be one of the safe zones for earthquakes any more. According to the records of the historical records and recent earthquake events in Korea, the possibillty of disastrous seismic hazards cannot be ignored, Korea Earthquake Engineering Research Center (KEERC) and Earthquake Engineering Society of Korea(EESK) have been established by that consensus. In this paper, historical earthquake records and seismicity in Korea are reviewed. And the research activities and the research system for the earthquake hazards mitigation of KEERC are introduced and the efforts of ESSK to renovate seismic design code system and to optimize the protection levels against earthquake disasters is explained.

해저지진에 의해 촉발되는 파괴적인 지진해일은 지진의 진원지 부근은 물론 멀리 떨어진 해안지역에도 피해를 입힐 수 있다. 우리나라의 동해안은 많은 인구밀집지역과 원자력발전소가 위치하고 있어 예상하지 못한 지진해일의 내습으로부터 위험에 노출되어 있다. 본 논문에서는 지진해일 현장조사, 방재대책 및 추가적으로 연구해야 할 주제 등에 대하여 기술한다.

우리나라 폐기물관리법(구폐기물관리법)에서는1997년 재활용 규정을 제정한 이후, 사업장일반폐기물 중 석탄재, 점토점결주물사, 광재 및 무기성오니 등은 성토재 등으로 재활용할 수 있도록 해왔다. 그러나 해당 폐기물에는 아연, 납, 불소 등의 성분이 현행 토양오염 우려기준을 초과하는 경우가 있어, 과거 적법한 절차를 거쳐 폐기물을 재활용하였더라도 토양환경보전법에 따라 부지정화를 시행하는 사례가 종종 보고된다. 과거 폐기물을 성토재 등으로 재활용한 지역의 부지정화를 시행하는 경우, 토양과 폐기물은 최대한 분리/선별한 후에 각각 토양환경보전법과 폐기물관리법에 따라 처리하는 것이 원칙이다. 또한, 토양정화 비용과 폐기물처리 비용이 차이를 고려할 때, 경제적인 측면에서도 토양과 폐기물을 분리하는 것이 매우 중요하다. 하지만, 앞서 언급한 석탄재 등의 폐기물은 육안상 토양과 구별이 어렵고, 물리적 성상(입도 및 밀도) 또한 토양과 유사하기 때문에 일반적인 방법으로는 선별이 불가능한 문제가 있다. 본 논문에서는 TPH, 아연, 비소 등이 1지역 토양오염우려기준을 초과하는 폐기물 재활용지역을 대상으로 XRF분석을 실시하였고, 조사결과를 토대로 오염토양과 폐기물에 대한 분류기준 수립하고 ‘토양환경보전법’과 ‘폐기물관리법’의 적용여부를 판단하는 자료로 활용하고자 하였다. XRF를 이용하여 측정한 주요 성분을 ternary diagram (SiO2, CaO/MgO, Al2O3/Fe2O3/기타)을 이용하여 비교하였으며, 오염토사와 폐기물은 성분비에 따라 구별이 가능함을 확인하였다. 토양오염도 조사결과 폐기물시료의 TPH, 아연, 비소의 농도는 토양에 비해 3~4배 정도 높게 측정되어, 폐기물을 분리/선별하는 것만으로도 토양오염도를 상당 부분 낮출 수 있을 것으로 기대된다.

우리나라의 메탄가스 배출량은 2014년 기준 26.6백만톤 CO2eq 수준으로, 이중 약 27% (7.3 백만톤 CO2eq)는 폐기물매립지에서 유출되고 있다. 매립지에서의 메탄유출을 저감하는 가장 이상적인 방법은 매립가스를 포집하여 에너지화하는 “매립가스 자원화” 방식이다. 그러나, 이를 위해서는 가스포집시설, 가스정제시설 및 발전설비 등의 설비투자가 필요하며, 매립가스 발생량이 2~3 N㎥/min (메탄가스 농도 35%~50%)이상의 대규모 매립지에서만 경제성 확보가 가능하다고 알려져 있다. 이런 이유로 230개소의 매립지 중 17개 시설에서만 매립가스 자원화 시설을 운영하고 있으며, 대부분의 중소규모 매립지에서는 메탄유출에 대한 별다른 대책이 없는 실정이다. 본 연구에서는 중소규모의 매립지 5개소를 선정하여 “공기주입을 통한 호기성 매립지 전환” 및 “매립지복토층을 이용한 생물학적 메탄산화 기술”의 메탄저감 성능과 경제성을 검토하였고 “매립가스 자원화”와 비교하였다. 매립가스 자원화를 검토하기 위한 매립가스 발생량은 LandGem 모델을 이용하여 산정하였으며, 폐기물의 성상(메탄잠재발생량 및 메탄발생속도추정)및 매립량은 환경부 통계자료를 이용하였다. 공기주입에 따른 호기성전환 비율은 주입압에 따른 유효반경을 산정하여 추정하였으며, 복토층에서의 메탄산화 효율은 문헌조사를 통해 결정하였다. 기술검토 결과 공기주입과 복토층 메탄산화기술을 조합하는 경우 70~85% 수준까지 메탄유출을 저감할 수 있는 것으로 추정되었으며, 중소규모 매립지의 경우 매립가스 자원화와 비교하여 상대적으로 우수한 경제성을 나타냈다.

This study was conducted to investigate the antibacterial, antioxidant, and in vitro greenhouse gas mitigation activities of fermented Scutellaria baicalensis Georgi extract. Seven starter cultures were used, comprising four of lactic acid bacteria and three of Saccharomyces cerevisiae. Ten grams of S. baicalensis Georgi powder was diluted in 90 mL autoclaved MRS broth. Each seed culture was inoculated with 3-10% (v/v) S. baicalensis Georgi MRS broth and incubated at 30℃ for 48 h. Among the starter cultures used, only Lactobacillus plantarum EJ43 could withstand the fermentation conditions. This fermentation broth was dried and extracted with ethanol to assess its antibacterial, antioxidant, and in vitro methane mitigation activities. The extract of S. baicalensis Georgi fermented by L. plantarum EJ43 (SBLp) showed higher antibacterial activity (bigger clear zone) compared to the unfermented S. baicalensis Georgi extract (SB0). SBLp also presented 1.2 folds higher antioxidant activity than SB0. During in vitro rumen fermentation, SBLp showed reduction in methane production compared to SB0 or the control. In conclusion, fermentation by L. plantarum EJ43 may enhance antibacterial and antioxidant activities of S. baicalensis Georgi and decrease enteric methane production.

Drought stress is a major agricultural limitation to crop productivity worldwide, especially by which leafy vegetables, plant leaves eaten as vegetable, could be more lethal. The study was carried out to know the effect of drought tolerance plant growth promoting bacteria (PGPB) on water stress of kale seedlings. A total of 146 morphologically distinct bacterial colonies were isolated from bulk soil and rhizosphere soil of leafy vegetables and screened for plant growth promoting microbioassay in greenhouse. Out of them the isolate SB19 significantly promoted the growth of kale seedlings in increasement of about 42% of plant height (14.1 ㎝), 148% of leaf area (19.0 ㎠) and 138% of shoot fresh weight (1662.5 ㎎) attained by the bacterially treated plants compared to distilled water treated control (9.9 ㎝, 7.7 ㎠, 698.8 ㎎). Shoot water content of SB19 treated kale seedlings (1393.8 ㎎) was also increased about 152% compared with control (552.5 ㎎). The SB19 isolated from bulk soil of kale plant in Iksan, Korea, was identified as species of Bacillus based on 16S rRNA gene sequencing analysis. We evaluated the effect of drought tolerance by the Bacillus sp. SB19 on kale seedlings at 7th and 14th days following the onset of the water stress and watering was only at 7th day in the middle of test. In the survey of 7th and 14th day, there were mitigation effect of drought stress in kale seedlings treated with 106 and 107 cell mL-1 of SB19 compared to distilled water treated control. Especially, there were more effective mitigation of drought damage in kale seedlings treated with 107 cell mL-1 than 106 cell mL-1. Further, although drought injury of bacterially treated kale seedlings were not improved at 14th day compared with 7th day, drought injury of 107 cell mL-1 of SB19 treated kale seedlings were not happen rapidly but developed over a longer period of time than 106 cell mL-1 of SB19 or control. The diffidence of results might be caused by the concentration of bacterial suspension. This study suggests that beneficial plant-microbe interaction could be a important role of enhancement of water availability and also provide a good method for improving quality of leafy vegetables under water stress conditions.

Mussels are stubborn organism attached to solid substrate by byssus threads and caused operational problems in utility of power generating stations. Sole and combined usage of ultrasonic (28 kHz- and 42 kHz- frequencies) and hydrogen peroxide (H2O2) has studied for control of blue mussel larvae and adult stage in seawater condition. A theoretical wo rking model using disinfection (Chick and Watson type) approaches is presented based on helpful results of experiments. This study also demonstrate that the combined treatment (ultra-sonication with H2O2) is overall highly efficient than individual treatment would, but on the basis of exposure time, the ultra-sonication was the most efficient among them. Therefore the development of sole and combined technique might be effective practical mitigation strategy against mussel attachment for water handling facilities.

Urban Heat Island has become a serious problem in urban area. Tree is considered as effective measure for mitigating urban heat. The purpose of this study is reviewing urban heat island mitigation effect of tree, focusing on evaluation indices related to temperature reduction. We selected 49 previous studies and classified studies considering type of site and variables related to mitigate urban heat. Studies were classified as tree, vegetation, green roof/wall and green area. Variables of each group were categorized as space, function, individual and environment variables. Each study site showed different mitigation effects and considered different variables. Therefore, plans or designs for green area in urban area should consider differences among sites and use integrated evaluation indices including humidity and wind speed for mitigating urban heat.

Background : Ginseng farmers prefer first planted field because of replant failure. But the accumulation of nutrients is higher in the first planted field due to using large amounts of chemical fertilizers and manure. The higher phosphate concentration in preparation field decreased emergence ratio and occurred leaf chlorosis in ginseng. The purpose of this study was to develop a technology for reducing phosphate concentration in preparation field of ginseng. Methods and Results : This study was performed in farm's fild located Yeongju in 2015. Treatment of plots consisted of sudangrass, maize, deep plowing + sudangrass and microbes(Rhodobacter sphaeroides, Bacillus subtilis, streptomyces griseus) + sudangrass. sudangrass and maize were sown in early May to 5kg / 10a. Microbes diluted 500 times were treated to drench the soil before sowing crops(400L/10a). The main survey was yield of crop, soil chemical properties, reduction ratio of phosphate and changes in available phosphate. Reduction ratio of phosphate in the plot of maize and Rhodobacter sphaeroides were 27.9% and 24.3%, respectively, which were higher 2∼5% than the control plot. Fresh weight yield was the highest with 11.1ton / 10a in the plot of maize and ratio of dry matter was the highest with 27% in the plot of maize. Conclusion : The phosphate removal ability of maize was better than sudangrass in phosphate accumulation soil. Subsoil reversed using excavators used by some farmers could not mitigate of phosphate and salts concentration in preparation field. The soil that phosphate concentration is more than 1,000mg/kg is required a long-term management.

POST-TENSIONING GROUT PROBLEMS Bonded post-tensioned structures are at increased risk of corrosion and failure of the tendons when there are defects in the installed grout. The most common grout problems (defects) include: • Voids: Voids are common at high points of tendon ducts as a result of grout bleeding and inadequate grouting. Standard cement/water grout has typically produced grout with 3 to 5% bleed. • Chloride contaminated grout: Chloride contamination may result from the use of chloride contaminated grout or mixing water or the long-term exposure of the structure to marine environments or de-icing salts. • Soft grout: Soft grout may be created if excessive water is added during grout mixing, and wick induced bleeding causes localized grout with high water-cement ratio. THE SOLUTION The Post-Tech PTI Impregnation system has been developed to mitigate corrosion caused by these problems. The system utilizes the interstitial spaces between the wires of each strand in a multi-strand tendon to deliver (transfer) a unique corrosion inhibiting, impregnation material along the length of the cable. The impregnation material seeps between the wires of the strands to impregnate the surrounding grout or concrete. The impregnation material is designed to form a corrosion-resistant film on any exposed steel surfaces such as steel strands which are exposed in grout voids, and to make the grout more corrosion and moisture resistant. Laboratory Confirmation Laboratory confirmation was completed on tendon specimens provided by one DOT and grouted “lollipop” samples. The tendon specimens provided to Vector were sections of external tendons which had been removed from an existing bridge. Lolipop samples comprised a single strand section which was centrally grouted in a cylindrical block of prepackaged PT grout. Laboratory testing confirmed the ability of the impregnation material to travel along the length of the specimen, to soak into the grout surroundingthe strands and to pass from strand to strand across the cross-section of a grouted tendon. Accelerated laboratory testing also confirmed the ability of the impregnation process to reduce corrosion by over 90%. Field Demonstration and case study The demonstration project was completed on external tendons in a box girder bridge in Jacksonville, FL (I-95 / I-295 Interchange). The demonstration project verified the capability of impregnating the full length of 256’ and 205’ grouted tendons from end anchorage locations, the capability of impregnating up to 100’ in each direction from a mid-point location, and the capability of the impregnation material to penetrate the grout adjacent to the strand. FDOT has implemented PTI Impregnation on the tendons of I-4 Connector in which soft grout was found. All selected tendons were successfully impregnated. Free water/moisture was pushed out of the tendons during the impregnating process. CONCLUSIONS Laboratory testing confirmed the ability of the impregnation material to travel along the length of the specimen, to soak into the grout surrounding a strand and to reduce corrosion by over 90% when exposed in an accelerated corrosion cell. Field demonstration at the I-95/295 Interchange in Jacksonville, Florida and Implementation on I-4 Connector in Tampa, Florida has demonstrated the following: • All strands of 256’ long grouted tendons can be impregnated full-length from an end anchorage location, • Impregnation material can flow up to 100’ in each direction from a mid-point location,. • Impregnation material can penetrate grout adjacent to a grouted strand, and • Free water/moisture can be pushed out of the tendons during the impregnation process.