The Study On The Engineering Character Of Backfill Material And The Backfill Quality Detection At Back Of The Bridge And Culvert In Dianlin Expressway

With the rapid development of the national economy, road construction increasing mileage, especially the rapid development of high-grade highways, many of the problems have been exposed, one of highway quality problems in China is vehicle bump,which is caused by the bridge abutment uneven settlement transition section.This paper relies on the Dianlin expressway scientific research project that is Study on Backfill Technology for the Back of Bridges and Culverts of Dianlin Expressway.Combining with Dianlin expressway's own characteristics,5of representative the backs of bridges and culverts which were tracked throughout the design, construction, testing and evaluation process were selected,Combining with Dianlin expressway's engineering geological conditions and the principle of economy, reasonableness the appropriate backfill material that is analyzed the engineering properties of backfill materials by the indoor test was choosed to the expressway. Analyzing a large number of test data of the outdoor test, we put forward testing and evaluation methods of the BridgeFrom the design, construction to testing three areas, a bridge and culvert backfill quality evaluation index system is builded.The comprehensive evaluation model was established by using the method of fuzzy mathematics. Finally, CoMParing the field test indicators with mathematical methods of evaluation results, we evaluate quality backfill of the Dian Lian expressway. Following the works, acquire the understanding and results in the below:(1) By researching of domestic and foreign Bridge abutment back?? materials, combining with Dianlin expressway's geological engineering conditions and taking into account cost-effective project, the as backfill material was selected and had separation test, coMPaction test,triaxial test.Using Cu,Cc,ρd,ω,c,φas the index ,it is analyzed the engineering properties.The graded broken stone was thougt the favorable backfill material;(2) Combining Rayleigh wave method ,the field bearing plate test with coMPactness test, three test method which ia analyzed the advantages ,disadvantages and suitability were detected the esquality backfill of Dianlin expressway. The evaluation standard of three detection methods were given, the average wave velocityV_S>250m/s before grouting ,after grouting the average wave velocityV_S>500m/s in Rayleigh wave test, the average wave velocityVS>300m/s in rigid-flexibility transition treatment measure.Using the field bearing plate test,when the content of gravel is more than 90%,modulus of resilienceis higher than 70MPa, meanwhile coMPactness is above 96% on all the experimental points;(3) Analyzing the data and talking about the correlation of the three test methods, Rayleigh wave and modulus have a good correlationd and the relation is E₀ = 0.2692V_R^1.178,so they have the same detection effect which is equivalent in esquality backfill of Dianlin expressway. Rayleigh wave , modulus and coMPactness have a bad correlationd because the hole collapse or coMPaction through 100is taken place to coMPactness test,which is considered limitations in test.(4) Established fuzzy comprehensive evaluation model of bridge abutment backfill quality that design, construction, detection were selected by using AHP and fuzzy comprehensive evaluation method. It is secondary-level of Fuzzy comprehensive evaluation model, AHP was used for the weight calculation of evaluation factors.?? evaluation result is good at the experimental points of Dianlin expressway.(5) Combining Rayleigh wave method ,the field bearing plate test with coMPactness test, there is a joint detection (Including the arrangement of the measuring point and detection steps)to the esquality backfill of Dianlin expressway by different treatment methods.Using the Rayleigh wave ,the detection results is well;using rigid-flexibility transition treatment measure,first it is defined the emphasizing back of abutment on detecting,then it is used the two methods to test the back of abutment jiontly.evaluation standard that modulus of resilience,coMPactness and settlement four indicators evaluate comprehensivly was recommended in the esquality backfill of Dianlin expressway.