Research On Engineering Characteristics Of Retaining Structures For Riverside Roadbed In Mountainous Area

Most highways in mountainous area were/are projected along rivers. Rock-soil filled roadbed is one of the main roadbed types. Many protective measures have been adopted ,for example , Jiangqi stone or dry-block, cast-in-place concrete, pre-cast concrete block structure forms. Using these structures has played a certain role in maintaining the stability of the bank slope , but many local protection projects were ineffective. More practices of riverside roadbed protection show that increased investment projects roadbed, to a large extent, is due to structural problems caused by protective changes .Therefore, according to engineering properties of protective Structure for Riverside Roadbed, designing the reasonable structure has become the Most concerned matter of design and construction unit.Based on former work, several main researches in the paper are as follows:(1) Summarized the present the main pattern of riverside roadbed protection, divides into two big kinds according to its structure and the function:â‘ Direct protection: plant slope protection, riprap revetment , retaining wall protection, Apron protection, Slope paving ;â‘¡Indirect slope protection: groin and groin group , And proposed the suitable condition of each kind .(2) From on macroscopic the influence along the river roadbed and its the protection structural stability factor induction is two aspects:â‘ shearing stress increase In slope in vivo;â‘¡The slippery belt gneiss intensity reduces. And embarked from these two aspects, unifying the scene investigation material, taking retaining wal as the example, and inducing the main plant disease of protection structure : overturning damage, overall fracture, basis brushed, sliding damage, piping. And has analyzed its origin mechanism, pointed proposed the punishment countermeasure:â‘ Optimization detailing;â‘¡Uses the raised wedge foundation;â‘¢Control seepage distortion;â‘£Uses the Gabions protection as well as the Ecological protection technology;(3) According to the characteristic of riverside roadbed, has analyzed on the river straight road and the curve different washes out the rule. three mainly factor influence the washing out the depth : the geometry boundary condition, the fluent factor, the river bed nature factor. Embarking from these three factors, the Paper carried on the existing washed out the depth formula and discovered the formula of Jiang Huanzhang is reasonable.(4) Carried on the simplification to the riverside roadbed retaining wall, regarding the drainage system at the back wall, at the bottom of filling ,and at the wall-soil interface , proposed the earth pressure computational method, through the example analysis. Proposed has the conclusion suggestion:â‘ It is very important to the stability of riverside roadbed retaining wall that guaranteeing the subgrade drainage system the validity;â‘¡The drainage system at the bottom of filling is better.(5) Adopted indoor physic model test to study the riverside roadbed retaining wall. Analyzed model test results to get the distribution of pore water pressure under different drainage conditions. Based on the basic theory of seepage, carried on numerical analysis using stability analysis method of PLAXIS and calculation theory of fluid-mechanical interaction. Analyzed and discussed the changing of seepage field and stress field under such conditions as ascending and descending of water level And then compare the results of numerical analysis with that of physic model test.(6) Economics,safeties,feasibility for construction and applicability were considered in natural determined and valuable determined.Based on the Euclid distance,the object function was set up,and the fuzzy multiple attribute decision making process was utilized to deal with the uncertain information and the difficultly valued information.which solve the multiple attribute problem successfully.The results indicate that the method can effectively solve the problem of the choice of the optimal form in fuzzy environment.According to suitable condition of each kind of protection structure, choose the suitable protection pattern, and effectively prevent and control the plant disease which possibly occurs, certainly can have a satisfactory result.