• Title/Summary/Keyword: consolidation theory

Search Result 195, Processing Time 0.026 seconds

Strength Characteristics of Clay Soil by Preconsolidation Pressure (선행하중(先行荷重)에 의한 점토(粘土)의 강도특성(强度特性))

  • Chon, Yong-Baek;Shin, Young-Gi
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.6 no.3
    • /
    • pp.185-192
    • /
    • 2003
  • This study consolidation undrain Triaxial Compression Tests using constant confining pressure in clay that receive preconsolidation stress that is different and, void ratio, pore water pressure coefficient, shear strength compare with another thing theory and studied analyzing change relation of elastic modules. The summary of analysis is follows: If preconsolidation stress increases in same confining stress in relation of preconsolidation stress and deviator stress, deviator stress is proportional and increased. Can know that excess void pressure is proportional and decreases in size of preconsolidation stress in same confining stress state if preconsolidation stress increases preconsolidation stress and relation of excess void pressure. Also, over consolidated state can assume that this is thing by Dilatancy's effect though excess void pressure decreased remarkably. Preconsolidation stress and relation of stress path can know that shear strength degree increases preconsolidation stress increases, and specially, preconsolidation stress was appear in stress path form of overconsolidated state case of clay that receive at 300, 400, 500kPa in 100, 150kPa's deviator stress.

  • PDF

Study on correlation of acoustic emission and plastic strain based on coal-rock damage theory

  • Jin, Peijian;Wang, Enyuan;Song, Dazhao
    • Geomechanics and Engineering
    • /
    • v.12 no.4
    • /
    • pp.627-637
    • /
    • 2017
  • The high positive correlation between plastic strain of loaded coal-rock and AE (acoustic emission) characteristic parameter was studied and proved through AE experiment during coal-rock uniaxial compression process. The results show that plastic strain in the whole process of uniaxial compression can be gained through the experiment. Moreover, coal-rock loaded process can be divided into four phases through analyzing the change of the plastic strain curve : pressure consolidation phase, apparent linear elastic phase, accelerated deformation phase, rupture and development phase, which corresponds to conventional elastic-plastic change law of loaded coal-rock. The theoretical curve of damage constitutive model is in high agreement with the experimental curve. So the damage evolution law of coal rock damage can be indicated by both acoustic emission and plastic strain. The results have great academic and realistic significance for further study of both AE signal characteristics during loaded coal-rock damaged process and the forecasting of coal-rock dynamic disasters.

A study on the shear strength considering matric suction for an unsaturated soil (모관흡수력을 고려한 불포화토의 전단강도에 대한 연구)

  • Oh, Se-Boong;Kim, Tae-Kyung
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2008.03a
    • /
    • pp.105-110
    • /
    • 2008
  • The behaviour of an unsaturated soil was analyzed by performing $K_0$ consolidated triaxial tests. Unsaturated triaxial tests were performed with matric suctions for weathered soils and could catch stress paths under consolidation and stress-strain relationships under shear. As a result, both isotropic and $K_0$ conditions had similar shear strength envelopes in the same matric suction. Especially, strength parameters could obtain by stress variables based on critical state theory reasonably which was better than those by Mohr circles at failure.

  • PDF

A Combinational Method to Determining Identical Entities from Heterogeneous Knowledge Graphs

  • Kim, Haklae
    • Journal of Information Science Theory and Practice
    • /
    • v.6 no.3
    • /
    • pp.6-15
    • /
    • 2018
  • With the increasing demand for intelligent services, knowledge graph technologies have attracted much attention. Various application-specific knowledge bases have been developed in industry and academia. In particular, open knowledge bases play an important role for constructing a new knowledge base by serving as a reference data source. However, identifying the same entities among heterogeneous knowledge sources is not trivial. This study focuses on extracting and determining exact and precise entities, which is essential for merging and fusing various knowledge sources. To achieve this, several algorithms for extracting the same entities are proposed and then their performance is evaluated using real-world knowledge sources.

Undrained solution for cavity expansion in strength degradation and tresca soils

  • Li, Chao;Zou, Jin-feng;Sheng, Yu-ming
    • Geomechanics and Engineering
    • /
    • v.21 no.6
    • /
    • pp.527-536
    • /
    • 2020
  • An elastic-plastic solution for cavity expansion problem considering strength degradation, undrained condition and initial anisotropic in-situ stress is established based on the Tresca yield criterion and cavity expansion theory. Assumptions of large-strain for plastic region and small-strain for elastic region are adopted, respectively. The initial in-situ stress state of natural soil mass may be anisotropic caused by consolidation history, and the strength degradation of soil mass is caused by structural damage of soil mass in the process of loading analysis (cavity expansion process). Finally, the published solutions are conducted to verify the suitability of this elastic-plastic solution, and the parametric studies are investigated in order to the significance of this study for in-situ soil test.

Parametric study on flexible footing resting on partially saturated soil

  • Singh, Mandeep;Sawant, V.A.
    • Coupled systems mechanics
    • /
    • v.3 no.2
    • /
    • pp.233-245
    • /
    • 2014
  • Coupled finite element analysis is carried out to study the effect of degree of saturation on the vertical displacements and pore water pressures simultaneously by developing a FORTRAN90 code. The finite element formulation adopted in the present study is based upon Biot's consolidation theory to include partially saturated soils. Numerical methods are applied to a two-dimensional plane strain strip footing (flexible) problem and the effect of variable degree of saturation on the response of excess pore water pressure dissipation and settlement of the footing is studied. The immediate settlement in the case of partly saturated soils is larger than that of a fully saturated soil, the reason being the presence of pore air in partially saturated soils. On the other hand, the excess pore water pressure for partially saturated soil are smaller than those for fully saturated soil.

Numerical Analysis on Deformation of Soft Clays Reinforced with Rigid Materials (말합연약식반의 변형위석에 관한 수치해석)

  • Gang, Byeong-Seon;Park, Byeong-Gi;Jeong, Jin-Seop
    • Geotechnical Engineering
    • /
    • v.1 no.2
    • /
    • pp.27-40
    • /
    • 1985
  • This study aims at the development of computer Program for the deformation analysis of soft clay layers, and using this computer program, study the constraint effect of deformation- heaving, lateral displacement-of the soft clay layers reinforced with sheet pile at the tip of banking or improvement of soft clay layer up to hard strata, under intact state (natural) and the state of vertical drain respectively. For this study, Biot's consolidation theories and modified Cam-clay theory for constitutive equation for FEMI were selected and coupled governing equation, and christian-Boehmer's technique was applied to solve the coupled relationship. The following results are obtained. 1. Sheet pile or improvement of soft clay layer to the hard strata work well against the settlement of neighboring ground. B. In view of restriction of heaving or lateral displacement, sheet pile is not supposed to be of use. 3. Sheet pile is of effect only when vertical drain is constructed for acceleration of consolidation and load increases gradually. B. The larger the rigidity of improvement of layer to hard strata is, the less settlement occurs.

  • PDF

Reclamation and Soil Improvement on Ultra Soft Soil (II) - Soil Improvement (초연약지반의 매립 및 지반개량 사례 연구 (II) - 지반개량)

  • Na, Yung-Mook;Kim, Hee-Hong;Kwon, Duk-Woo
    • Journal of the Korean GEO-environmental Society
    • /
    • v.6 no.1
    • /
    • pp.33-44
    • /
    • 2005
  • The 'Silt Pond' is 180 hectares in size and contained ultra soft slurry-like soil varying between 3 to 20 meters in thickness. Soil improvement work in the Silt Pond commenced by installing vertical drains in the mid of 1996, following completion of sand spreading up to +4.0m CD. Prior to soil improvement work in the main area of Silt Pond, experimental tests including laboratory tests with a large diameter consolidation cell and pilot tests were carried out to investigate the deformation behavior of an extremely soft soil. Due to its high compressibility, large strain usually occurred in the initial stage of deformation does not comply with Terzaghi's one dimensional consolidation theory. Taking into consideration experimental test results, the soil improvement works were carried out in main area of Silt Pond containing ultra soft soil. This paper presents the case study on improvement of ultra-soft soil.

  • PDF

A Comparative Study between BPNN and RNN on the Settlement Prediction during Soft Ground Embankment (연약지반상의 성토시 침하예측에 대한 BPNN과 RNN의 비교 연구)

  • Kim, Dong-Sik;Chae, Young-Su;Kim, Young-Su;Kim, Hyun-Dong;Kim, Seon Hyung
    • Journal of the Society of Disaster Information
    • /
    • v.3 no.1
    • /
    • pp.37-53
    • /
    • 2007
  • Various difficult problems occur due to insufficient bearing capacity or excessive settlements when constructing roads or large complexes. Accurate predictions on the final settlement and consolidation time can help in choosing the ground improvement method and thus enables to save time and expense of the whole project. Asaoka's method is probably the most frequently used for settlement prediction which are based on Terzaghi's one dimensional consolidation theory. Empirical formulae such as Hyperbolic method and Hoshino's method are also often used. However, it is known that the settlement predicted by these methods do not match with the actual settlements. Furthermore these methods cannot be used at design stage when there is no measured data. To find an elaborate method in predicting settlement in embankments using various test results and actual settlement data from domestic sites, Back-Propagation Neural Network(BPNN) and Recurrent Neural Network(RNN) were employed and the most suitable model structures were obtained. Predicted settlement values by the developed models were compared with the measured values as well as numerical analysis results. Analysis of the results showed that RNN yielded more compatible predictions with actual data than BPNN and predictions using cone penetration resistance were closer to actual data than predictions using SPT results. Also, it was found that the developed method were very competitive with the numerical analysis considering the number of input data, complexity and effort in modelling. It is believed that RNN using cone penetration test results can make a highly efficient tool in predicting settlements if enough field data can be obtained.

  • PDF

Applying TRIZ Theory to Fashion Design - Focused on Rei Kawakubo's Fashion Design - (트리즈(TRIZ)이론에 의한 패션디자인의 적용 - 레이 가와쿠보의 패션디자인을 중심으로 -)

  • Kim, Sung Hyon;Kim, Min-Ja
    • Journal of the Korean Society of Costume
    • /
    • v.62 no.7
    • /
    • pp.79-96
    • /
    • 2012
  • Creativity is a rising topic in the current society. The emphasis on creativity is valued as a key factor for success in all areas including but not limited to politics, economy, culture, arts and design. The field of Fashion design is probably one of the few areas that talk about creativity as a necessary quality to survive. The purpose of this study is to introduce TRIZ(Teoriya Reshniya Izobretatelsskikh Sadatch) as a theoretical tool to generate creativity in fashion design. TRIZ is a creative method of problem solving based on data analysis of outcomes invented by engineering. The fundamental concept of TRIZ has been researched through documentary studies, and practical case studies of product designs are used. Fashion design cases from Comme des Garcons by Rei Kawakubo are used to apply TRIZ in fashion design. Rei Kawakubo's design philosophy has been studied through fashion writings and visual sources in books, exhibition catalog, www. style. com and online shopping mall sites. This study has selected four principles among forty inventive theories of TRIZ: segmentation; asymmetry; consolidation; and preliminary action to apply to Rei Kawakubo's fashion design. As a result, TRIZ can be applicable to fashion design as a creative thinking methodology. By using the four principles of TRIZ, this study shows how Rei Kawakubo's design enhanced its efficiency and aesthetics of the products and was distinguished from existing items. It is meaningful to demonstrate a possibility of adopting engineering based creative methodology in fashion design to widen the perspective and to raise a question for the need of interdisciplinary creative methodology with traditional aesthetic approach in fashion design.