• Title/Summary/Keyword: ground strain

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THE EFFECTS OF PARTIAL REPLACEMENT OF SOYABEAN MEAL WITH BOILED FEATHER MEAL ON THE PERFORMANCE OF BROILER CHICKENS

  • Ochetim, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.6 no.4
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    • pp.597-600
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    • 1993
  • An experiment was conducted using 160 Arbor Acres broiler strain of chickens to evaluate the effects of partial replacement of soyabean meal with feather meal on the diets of broiler chickens raised from day old to 8 weeks of age. Feathers, obtained from a local poultry processing plant, were boiled in water for 30 minutes, sun-dried and ground using a 2 mm sieve for inclusion into the experimental diets at 0, 1.5, 3.0 and 4.5% levels at the expense of soyabean meal. The feather meal was assayed and found to contain 86.5% crude protein and to be low in lysine, methionine and histidine amino acids. The inclusion of such processed feather meal up to 3% in the diet did not (p>0.05) affect growth or feed conversion ratio. However, the highest level of inclusion of feather meal in the diet, 4.5%, significantly reduced both growth rate and feed conversion ratio of the birds. The results of this experiment showed that up to 3% of water-boiled feather meal, which represents 12% of dietary protein, the equivalent of 6% level of use of soyabean meal in the diet, can be successfully included as a protein source in the diets of broiler chickens.

Structural Performance Verification of RDT Girder Bridge Feasible to Fill with Planting Ground (식재기반을 담는 RDT 거더교의 구조성능 검증)

  • Ha, Tae-Yul;Han, Jong-Wook;Yang, In-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.3
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    • pp.2219-2228
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    • 2015
  • The proposed RDT(Reversed Double T) girder bridge is suitable to eco corridor, because of its cross section which resembles Korean alphabet vowel "ㅛ". The total height and cost of bridge would be reduced for its inner space containing some of plant soil. In this study, the performance of the RDT girder was assessed by comparing results of static test with those of nonlinear analysis. The cracking load of the RDT girder was evaluated more than two times of design load.

Cost-Effectiveness Evaluation of the Structure with Viscoelastic Dampers (점탄성감쇠기를 설치한 구조물의 비용효율성 평가)

  • 고현무;함대기;조상열
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2001.04a
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    • pp.387-393
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    • 2001
  • Installing vibration control devices in the structure rises as a solution instead of increasing structural strength considering construction cost. Especially, viscoelastic dampers show excellent vibration control performance at low cost and are easy to install in existing structures compared with other control devices. Therefore, cost-effectiveness of structure with viscoelastic dampers needs to be evaluated. Previous cost-effectiveness evaluation method for the seismically isolated structure(Koh et al., 1999;2000)is applied on the building structure with viscoelastic dampers, which combines optimal design and cost-effectiveness evaluation for seismically isolated structures based on minimum life-cycle cost concept. Input ground motion is modeled in the form of spectral density function to take into account acceleration and site coefficients. Damping of the viscoelastic damper is considered by modal strain energy method. Stiffness of shear building and shear area of viscoelastic damper are adopted as design variables for optimization. For the estimation of failure probability, transfer function of the structure with viscoelastic damper for spectral analysis is derived from the equation of motion. Results reveal that cost-effectiveness of the structure with viscoelastic dampers is relatively high in how seismic region and stiff soil condition.

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Diverse Application of ECC Designed with Ground Granulated Blast Furnace Slag

  • Kim, Jeong-Su;Kim, Yun-Yong;Kim, Jin-Keun
    • International Journal of Concrete Structures and Materials
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    • v.1 no.1
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    • pp.11-18
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    • 2007
  • In the recent design of high ductile engineered cementitious composites (ECC), optimizing both processing and mechanical properties for specific applications is critical. This study employs a method to develop useful ECC produced with slag particles (slag-ECC) in the field, which possesses different fluid properties to facilitate diverse types of processing (i.e., self-consolidating or spray processing). Control of rheological modulation was regarded as a key factor to allow the performance of the desired processing while retaining the ductile material properties. To control the rheological properties of the composite, the basic slag-ECC composition was initially obtained, determined based on micromechanics and steady-state cracking theory. The stability and consequent viscosity of the suspensions were then mediated by optimizing the dosage of the chemical and mineral admixtures. The rheological properties altered through this approach were revealed to be effective in obtaining ECC-hardened properties, represented by pseudo strain-hardening behavior in uniaxial tension, allowing the readily achievement of the desired function of the fresh ECC.

Strength Characteristics of Soil Cement Reinforced by Natural Hair Fiber

  • Son, Moorak;Lee, Jaeyong
    • Journal of the Korean GEO-environmental Society
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    • v.19 no.4
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    • pp.17-26
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    • 2018
  • This study systematically examines the changes in the compressive and tensile strength of soil cement reinforced by natural hair fiber, which is regularly produced from human. Extensive experimental tests of various test specimens have been carried out in a laboratory. Several factors are considered, including the soil type, amount of cement, amount of fiber, fiber length, loading type, and curing age. The test results indicate that both the compressive and tensile strengths are significantly affected by the fiber, either increasing or decreasing depending on the conditions. The increase in tensile strength is significant in the sand-based soil cement due to the tensile resistance of the fiber which is interlocked with the surrounding soil or cement particles. The natural fiber provides a larger strain to failure due to its extensibility, which allows greater deformation. Based on the test results, natural hair fibers can be an effective and environmentally friendly way to improve soil ground subjected to tensile loading, such as an embankment slope, road subgrade, or landfill, thus reducing the cost for cement and waste treatment. The study results provide a useful information of better understanding the mechanical behavior of natural hair fiber in soil cement and the practical use of waste materials in civil engineering. The findings can be practically applied for improving earth structures under tensile loading.

An Experimental Study on Grouting Effect for Ground Reinforcement (지반보강 그라우팅 효과에 관한 실험적 연구)

  • Park, Yong-Won;Lee, Goo-Young;Park, Jong-Ho;Hong, Sung-Soo
    • Proceedings of the Korean Geotechical Society Conference
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    • 2004.03b
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    • pp.399-406
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    • 2004
  • This paper is experimental study on the effect of improved soil strength which was grouted by pressure grouting method for prevent collapse the tunnel's face during excavate tunnel. This study performs to investigate the proper grouting pressure and grouting method through pressure grouting laboratory model tests using loose dense sandy soil using specially designed and fabricated device($180cm{\times}220cm{\times}300cm$) under changing condition of injection in this test The investigation is carried out through measuring the size and shape of grout bulb, elastic modulus by pressure-meter test Elastic modulus was estimated using relation stress with strain which is result the uni-direction compressive strength test for cured grouted bulb under water during 28days. From these test results, the amount of increased elastic modulus of grouted zone was suggested.

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A Model Test on Uplift Behavior of Plate Anchor (Plate Anchor의 인발거동에 관한 모형실험)

  • Kim, Seo Seong;Lee, Sang Duk;Koo, Ja Kap;Jeon, Mong Gak;Yoo, Keon Seon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.5
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    • pp.1219-1227
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    • 1994
  • For Determination of the ultimate uplift capacity, the failure mechanism of the foundation by uplift should be correctly known. However, studies on the variation of the failure mechanism with the embedment ratio of anchor plate among those factors governing the uplift resistance are scarce. In this study. in an attempt to observe more clearly the variation of the failure mechanism with embedment ratio and to check applicability of existing formulae for the ultimate uplift capacity. a model test was performed with ground made of carbon rods, simulating a plane strain conditions. As a result, failure characteristics of shallow and deep anchor conditions were clearly classified. It was found that the analysis of a shallow anchor should be made prior to determination of the ultimate uplift capacity of a deep anchor.

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Numerical modelling of Haarajoki test embankment on soft clays with and without PVDs

  • Yildiz, Abdulazim;Uysal, Firdevs
    • Geomechanics and Engineering
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    • v.8 no.5
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    • pp.707-726
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    • 2015
  • This paper investigates the time dependent behaviour of Haarajoki test embankment on soft structured clay deposit. Half of the embankment is constructed on an area improved with prefabricated vertical drains, while the other half is constructed on the natural deposit without any ground improvement. To analyse the PVD-improved subsoil, axisymmetric vertical drains were converted into equivalent plane strain conditions using three different approaches. The construction and consolidation of the embankment are analysed with the finite element method using a recently developed anisotropic model for time-dependent behaviour of soft clays. The constitutive model, namely ACM-S accounts for combined effects of plastic anisotropy, interparticle bonding and degradation of bonds and creep. For comparison, the problem is also analysed with isotropic Soft Soil Creep and Modified Cam Clay models. The results of the numerical analyses are compared with the field measurements. The results show that neglecting effects of anisotropy, destructuration and creep may lead to inaccurate predictions of soft clay response. Additionally, the numerical results show that the matching methods accurately predict the consolidation behaviour of the embankment on PVD improved soft clays and provide a useful tool for engineering practice.

Mechanical Characterization of Lead-Rubber Bearing by Horizontal Shear Tests (수평 전단시험에 의한 납 삽입 적층고무베어링의 기계적 특성 평가)

  • 전영선;최인길;유문식
    • Journal of the Earthquake Engineering Society of Korea
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    • v.5 no.6
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    • pp.1-10
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    • 2001
  • In this study, the horizontal loading tests of 10ton and 200ton capacity of LRB(lead-rubber bearing) were performed for the evaluation of the dynamic properties of the LRB. It is noted from the test results that dynamic properties of the LRB are dependent on the loading frequency, vertical load and shear strain. A Slender bearing subjected to large deformation will tend to develop plastic hinges in the end regions of the lead plug which will cause the failure of the lead plug. It is recommended that the appropriate mechanical properties of LRB considering the level of structural response and input ground motion should be used in the design of base isolated structures.

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Fatigue Strength Evaluation of LCV Leaf spring Considering Road Load Response II (도로 하중조건을 고려한 상용차 판스프링의 피로강도 평가 II)

  • Sohn, Il-Seon;Bae, Dong-Ho;Jung, Won-Seok;Jung, Won-Wook;Park, Sun-Cheol
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.1127-1132
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    • 2003
  • Suspension system of vehicle have enough endurance during its life time to protect passenger. Spring is one of major part of vehicle. Thus, a fatigue strength evaluation for leaf spring based on road load response was carried out. At first, strain of leaf spring is measured on the city condition and proving ground condition. And next, the damage analysis of road load response data was carried out. And fatigue test of leaf spring were also carried out. Based on -N life relation, fatigue life of leaf spring was evaluated at belgian mode, city mode and drawing test specification. After that, it is compared the design life of leaf spring and evaluated fatigue life by belgian mode, city mode and drawing test specification. From the above, the maximum load-fatigue life relation of leaf spring was defined by test. and new test target of belgian mode and city mode was proposed to accept design specification of leaf spring. It is expect that proposed test target can verify leaf spring fatigue endurance at specific road condition.

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