| Compared with the general roadbed,the high-filled roadbed has the characteristics of large filling height and poor compaction effect by ordinary compacting means.As the main means of high-fill compaction,the strong tamping method plays an important role in the construction of high-filling projects in mountainous areas.However,in the mountainous area,the high-filled roadbed filling materials usually use the mountain blasting or tunnel excavation to obtain the earth and stone materials,and the particle size changes greatly and the particle size exceeds 60 mm.The influence of the construction method of the strong tamping method on the existing buildings(structures)is not negligible.The impact on the safety of culvert structures is often neglected in the past norms and research.For the above problems,this paper takes Jianghe Road Phase II.The construction of the Longjinggou high-fill embankment in the project is based on the two aspects of the construction of the high-filling method and the influence of the strong construction load on the culvert.The summary of the theory of the strong consolidation is introduced through the introduction of parameters to improve the theoretical formula and utilization.Abaqus finite element analysis software was used to simulate the dynamic tamping construction,and the effects of strong tamping reinforcement and strong tamping load on culvert structure were analyzed.The main research contents and conclusions are as follows:1.Through the literature review at home and abroad,the paper summarizes and analyzes the reinforcement mode when different types of soil subgrade are treated by strong tamping,and the conclusion that the strong tamping reinforcement principle of earth and rock mixture is mainly dynamic compaction.Through the dimension analysis method and the introduction of new parameters,the calculation formula of the strength of the strong tamping reinforcement,the horizontal range of the strong tamping reinforcement,and the soil property index after the squatting are derived.2.Starting from the environmental impact of strong enthalpy,by summarizing and analyzing the influence of strong vibration at home and abroad,based on the random vibration law of mass,the formula of particle vibration law considering multiple slamming and different depths is obtained.3.Through the large-axis test of earth-rock mixture,the influence law of soil-rock mixture on the shear strength is influenced by factors such as earth-rock ratio and confining pressure.The shear strength parameters of the soil and stone mixture were obtained,which provided references for subsequent research.4.Using the Abaqus finite element software,the hammer-subgrade model is established based on the actual engineering and experimental parameters.The dynamic stress response and displacement distribution of the subgrade are analyzed.Finally,the law of different slamming times and effective reinforcement depth under different slamming energy is obtained.Specifically,for the 2000kN·m strong concrete construction,the effective reinforcement depth is 4.7m,the effective reinforcement level range is 4.6m,and the effective slamming times are 7-8 times.When the subgrade compaction is 94%,the vertical plastic strain inside the corresponding soil is 29.1%.5.Using the principle of finite element analysis,the hammer-subgrade-culvert model was established.The law that the stress and vibration state of the culvert under the horizontal distance of 5m,10 m and 20 m is 5m,10 m,15m,etc.,is affected by the strong construction load,and the stress and vibration velocity are checked according to the specifications.The safety of the culvert.The final conclusions indicate that the impact on the safety of culvert results should be considered during construction.According to the vibration speed standard,the safety distance is 9.1m when the culvert depth is 5m,the safety distance is 5.5m when the burial depth is 10 m,and the safety distance is 4.5m when the burial depth is 20 m. |
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