Summary of doctor thesis of engineerin: Research of earth embankment stability on natural ground

Purposes of the research Building a new method (method directly applicable limit theorem) evaluate soil stabilization in accordance with the actual working of the soil environment, the study contributes to the development of stable subgrade; applying the above method to build a computer program, set the tables and nomogram helps engineers quickly determine the height and slope of embankment limited.
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Summary of doctor thesis of engineerin: Research of earth embankment stability on natural ground MINISTRY OF EDUCATION & TRAINING UNIVERSITY OF TRANSPORT AND COMMUNICATIONS Do Thang RESEARCH OF EARTH EMBANKMENT STABILITY ON NATURAL GROUND Major: Highway Engineering Code: 62.58.02.05.01 SUMMARY OF DOCTOR THESIS OF ENGINEERING Hanoi - 2014 WORK TO BE COMPLETED IN LIST OF PUBLISHED WORKS UNIVERSITY OF TRANSPORT AND COMMUNICATIONS 1. Do Thang (2013). “Stress field in soil is obtained by using the theory of elastic and the theory of min (max)”. Vietnam Bridge and Road Magazine. 10/2013. pp. 30 - 33. SUPERVISORS: 2. Do Thang (2013). “Research of stability for vertical slope by limit 1: Prof. Dr Ha Huy Cuong analysis method”. Review of Ministry of Construction of VietNam. (Military University of Science and Technology) 11/ 2013. pp. 103 - 104. 2: PhD Vu Duc Sy 3. Do Thang (2014). “New method research earth embankment stability (University of Transport and Communications) on natural ground”. Review of Ministry of Construction of VietNam. 6/2014. Reviewers 1: Prof. Dr Nguyen Xuan Truc (National University of Civil Engineering) Reviewers 2: Prof. Dr Nguyen Van Quang (Hanoi Architectural University) Reviewers 3: Prof. PhD Nguyen Truong Tien (Vietnam Society Soil Mechnical and Geotechnical Engineering) The thesis is defended to the Council assessing doctoral dissertation at the case level: University of Transport and Communications at ….h…' ……, 2014. Thesis can be found in the library: 1. National Library VietNam 2. University Library of Transport and Communications 1 INTRODUCTION 1. The reason of selecting project Subgrade is an important part of highway. To ensure the stability of subgrade is a prerequisite to ensure the stability of the pavement structure. Research methodology stable subgrade is widely used in today's designs is limited equilibrium methods. Basic equations of this method consists of two balance equations (plane stress problem) and Mohr- Coulomb yield condition. However, the limit equilibrium method is not consider the phenomenon volume change of soil when using the yield condition Mohr- Coulomb. On the other hand, the basic equations above do not allow determining the stress state in the yield imperfections, ie not consider the stress state of the entire soil mass. Therefore, in the thesis research of earth embankment stability on natural ground is presented below, using theoretical min (max), author can apply directly limit theorem to study the stability of the overall soil mass and stability of the embankment on natural ground. 2. Purposes of the research Building a new method (method directly applicable limit theorem) evaluate soil stabilization in accordance with the actual working of the soil environment, the study contributes to the development of stable subgrade . Applying the above method to build a computer program, set the tables and nomogram helps engineers quickly determine the height and slope of embankment limited. In addition, using the lower limit theorems of the theory of limit analysis tells us that the stress distribution in the soil mass before ruin and slip surfaces occur in soil mass, freely given variables appropriate enhance soil stabilization when necessary. 3. Subjects and scope of the research Research subjects: The earth embankment on natural ground. Scope of the research: The research of the stability problem of earth embankment on natural background consider in the case of plane problems. 2 4. Scientific meanings and pratice of the project Soil is not so elastic material in plane problems, two balance equations are not sufficient to determine the three components of stress. Author used more conditions min (max) to have enough equations determine the stress state in the entire soil mass and directly applicable limit theorem for stability studies and natural embankment and foundation. In the thesis presents the various stability problems: limited intensity of the ground under load horizontally forward hard (Prandtl problem), block slope of dry sand , steep tomorrow so natural on under Business Use of the external ear and self-weight, trapezoidal embankment on so natural under the effect of self-weight. Since the study was able to draw conclusions and explanations and quantitative following: - The yield condition Mohr- Coulomb said materials with internal friction greater the bigger the load capacity. However, for embankment construction materials such as soil, sand, shred lascivious... the material has a large capacity unit new headquarters is the material guarantee a better slope stabilization. Practices embankment construction in our country attest to that. - Slip surface appears on the sliding surface slope and embankment surface when external load effects. - When study the stability of embankment only consider self weight of the soil does not appear on the slip surface on slope an ...