نوع مقاله : مقاله کامل پژوهشی
نویسندگان
1 دانشکده فنی و مهندسی دانشگاه تربیت مدرس تهران
2 دانشکده فنی و مهندسی، دانشگاه تربیت مدرس تهران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Trenchless technologies are mainly used for the construction of underground pipelines at deep depths, especially in urban areas. The pipe jacking method is a non-stop method in the construction of tunnels and underground channels. Although this method has many advantages, there are significant problems in different types of soils that have highly variable geotechnical properties. In this paper, considering the pipe jacking operation in soft soil and below the underground water level as an engineering field, the ground deformation in different directions as well as the ground surface uplift were investigated using numerical simulation. This study has focused on the factors that mainly affect the displacement of the ground, including the diameter, over burden, grout injection pressure, excavation face pressure, elastic modulus, friction angle and cohesion. The aim of this research is to provide a theoretical basis for controlling and reducing the ground deformation during pipe jacking operations. Numerical simulation was carried out using Plaxis finite element numerical software and considering a case study. In the following, the effect of each parameter on the ground deformation in three directions and the estimation of the amount of uplift and their exact location were also investigated. The relationship of each of the parameters with the lateral ground displacement was estimated and finally the effect of each of the different factors was measured using sensitivity analysis and the sensitivity index of each was determined. The results show that the diameter has the most sensitivity and the grout injection pressure have the least sensitivity compared to other factors in the lateral ground displacement. Therefore, more precision and accuracy should be used in estimating them in primary studies. The maximum ground surface uplift occurs about 8 meters (2.4D) ahead of the excavation head and then gradually decreases as it approaches the excavated site.
کلیدواژهها [English]
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