Study On The Mechanical Behavior And Design Method Of Highway Loess Dam-like Embankment

Highway loess dam-like embankment is one kind of road access and a dual-functionstorage buildings，under the premise of ensuring road transport，it has the function of keepwater， protect soil and improve water conservation，it has great significance to maintainsustainable economic development for the environment which is lack of water in the loessregion. Due to the different of water type，boundary conditions，earthquake or other high earthdam embankment and many different practical problems，research set of the dam-likeembankment design has great practical significance for the application.Papers has study the main problems encountered in reality dam-like embankment，include its mechanics dynam character，settlement calculations，stability，foundation designand processing，anti-seepage，dam location and structure type，dam geometry parameter，flood culverts and other issues. Use of finite element simulation and theoretical analysis，takeexample by successful experience of earth dam and high embankment，following six aspectsof progress are made.1. Numerical simulation analysis of the mechanics dynam character of the dam-likeembankment has been systematically studied， The influence that dam type embankmentsettlement physical and mechanical parameters of the influence law for：the sensitivity of theelastic modulus is segmented; severe change is very sensitive; change of strength is notsensitive. obtained the influence of the structure type parameters is: fill height， the changesof water level， slope angle is sensitive， horizontal seismic force is not sensitive. affectlaws of filling obtained as follows: severe material should be filled in the embankment innerand lower part， by contrast， the strength parameters cohesion and internal friction angle，should be outside of the embankment and upper part. The cross-section of upstreamembankment showing the direction of low， lower high concave curve.2. For the boundary conditions of "U"-type or "V"-type gully，using different groovesize， dam height dimensions and slope gradient combine models; using numerical simulationmethod simulates dam-type embankment settlement; introducting soil arching effect theorycalculates.This obtains that the embankment longitudinal section reserved for filling heightcurve form is " W"，" M"，" N" and straight type.This gives the curve form formula of criticalangle. By calculating analysis， we can obtain that ditch slope area is4times of dam height;in addition，the elastic modulus and severe of physical and mechanical parameters of thesurrounding soil of embankment greatly influence embankment arching，but the effects ofcohesion and internal friction angle to embankment arching can be ignored. When theembankment top length is fixed， the settlement value decrease with the increase of the widthof the bottom of embankment settlement3.Theory of stable calculations introduce water and seismic force， which derive the formula of the stability of the embankment dam type.In a conclusion，the overallstability and slope stability are required to take into account the principles. They propose damembankment should be in the ditch-type longitudinal moderate gully.On the slope stabilityshould consider more extreme phenomena and other conclusions. Adding water and selfearthquake dam-type power factor of the embankment slope stability calculations of VBprogram should be demonstrated by examples of theoretical calculation formula and give outthe corresponding content and related points of embankment dam stability calculations.4. Use of the knowledge of water seepage mechanics establish model， combination oftheory and numerical deduction argument come: Type embankment dam with a maximumwater level, that is the mean water level and the corresponding upper limit of the ideal upperlimit of high and low water level，the essential reasons of maximum water level is because ofcharacterized of upstream reservoirs under the big end up mold type.Based on the study of type in the dam embankment with a maximum water level, andwith its formula，aim at the problem that the dam sluice culvert-type played a poor role，researching the hydraulic calculations of the normal highway culvert, which has similaritiesand differences in the dam embankment. Introduce diving theory, correct calculation of earthdam hydrological detention capacity for the remaining storage capacity, and has beencalculated; the remaining capacity is calculated by diving theory geometry, which in theoryis essentially to solve the problem of water storage dam embankment type.5. Base on mature approach of foundation design and method and earth dam seepageprevention measures, design and processing methods, anti-leakage method be proposed andobtained the corresponding type of embankment dam site conditions. Propose selection of theembankment dam type and structure, embankment dam type geometry, drainage designmethods, design methods of the ancillary structures.6. Base on the results in primary and secondary research, the theoretical design of yellowearth dam embankment-type system is proposed. Main results are: the set of culvertconditions and flood force calculation, stability calculations, set aside the settlement method;secondary: the main consideration of site conditions is foundation and seepage stability;embankment of reasonable width, height is mainly by the highway design requirements todetermine; road embankment and the stability of the calculus of common experience ratedetermined; culvert spillway should be set on undisturbed soil; to enhance the design anddrainage protection works.