Analysis Of Settlement And Study On Quality Control Method For Rockfill Embankment

Along with the rapid development of higher grade highway construction in west of China, the rockfill embankment has become a major form of the expressway in mountainous area. When the rockfill embankment gets to a certain height, the self-weight load is huge, the automobile load also keep effecting, and thus great settlement occurs in the embankment. Besides, due to the high strength of rockfill material, compaction quality is hard to be ensured, it's also difficult to detect the compaction degree. Therefore, in combination with the West Item "Study on the construction, consolidation and test technology for rockfill embankment highway in karst area", the regularity, supervision of settlement, the control and detection method of compaction quality is systematacially and deeply studied in this paper.On the basic of study on the large amounts of observed settlement data and the mechanism and regularity of rockfill embankment settlement, a variable-weight forecasting method combined of normal models is put forward, which forecasts more precisely than any single model, with obvious advantages. Then in combination with the West Item, the scheme of settlement observation in the test rockfill embankment of Changzhang expressway was designed and put in practice, which obtained a great deal of valuable observted material. Furthermore, through an indoor model test, dynamic soil pressure, settlement and compaction degree of the model embankment was obtained under different water content, compaction equipment and frequency, compaction traits of rockfill embankment is further revealed. Besides, the technique was studied of detecting compaction degree for rockfill embankment with Rayleigh wave, using different exciting ways, wave test was carried out under different water content and compaction degree, taking advantages of DASP system, frequency spectrum and wave velocity was analysed. In comparison with the measured compaction degree by watering method, an experience relational expression is set up between the compaction degree of rockfill embankment and the velocity of Rayleigh wave. Finally, Marc software was used to make a finite element analysis on rockfill embankment characteristics under dynamic loads, adopting elastic-plastic analysis model and linear Mohr-Coulomb yield code, a 3-D dynamic response model was established, which calculates the transfer of soil pressure and deformation of embankment under vibrating loads, and analyses the wave characteristics under...