The Flexible Pipe Reinforced Grouting Test And Application Of New Technologies

In recent years, the development of economy has driven the fast development of the freeway. In the process of the freeway construction, due to the limitations of on-the-spot condition, good-sized construction machines are unable to use in some special sections, such as the transitional section in the intersection of the end of bridge, culvert and subgrade. It is more difficult to accomplish the high consolidation without good-sized construction machines participating in construction. In order to solve this problem, cement grouting technology can be adopted.In this thesis, the flexible tube reinforced grouting is accomplished by laying retired plastic grouting tube in advance to operate field single-point grouting test with final achievement of field grouting parameters, including the grouting pressure, grouting capacity, grouting diffusion radius and grouting controlling standard etc. By comparing the physical and mechanical properties of soil in field test area before and after grouting, the grouting effect in corresponding area can be verified. In recent years, with the development of computer technology, it is possible to adopt numerical simulation into grouting issue in uniform soil. The paper deals with the numerical simulation which applies discrete element program into flexible tube reinforced grouting field test. Following contributions are achieved by this thesis:(1) Through field test research, the laying distance, pre-burying mode, grouting parameters and grouting process of the flexible reinforced grouting tube can be obtained. It can provide references and guidance for such kind of backfill consolidation construction with this new technology;(2) By completing the field testing research, statistics can be obtained as followings: the average dry density of backfill has been improved nearly 10.17%, while the average void has decreased 31.12%; the bearing capacity of 27 days on natural maintenance is higher from 30% to 50% than that on normal compact construction; the penetration resistance of the N₁₀ and N_63.5 test (6 days on N₁₀ test and 27 days on N_63.5 test) on backfill is higher 20% to 70% than that on normal compaction construction.(3) The time-path curve of grouting pressure and grouting rate can be obtained through field test research.(4) The law between grouting diffusion range and grouting pressure under different ambient pressures can be obtainded by using numerical simulation method(5) Grouting parameters of the flexible reinforced grouting tube, including grouting pressure and the discrete radius of grouting, can be obtained by theory analysis.