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"The transportation or railway system constructors usually, wherever possible, build the transportation system on the ground surface and avoid the necessity of underground tunnelling. However, this is not always possible. In many locations, such as mountainous area, hilly area or urban area, the underground tunnelling have to be built. The main problem of underground tunnelling is the soil stability around the tunnel, and the problems continue to mount for long and big tunnel. Therefore in recent years, engineers try to find the method to predict and solve all aspect of ground responses induced by excavating and tunnelling.

For the past 30 years, the research for estimating an accurate prediction of ground deformation caused by tunnelling processes, have been a major engineering challenge all around the world. A good prediction of ground deformation due to tunnelling excavation and advancement is highly necessary to ensure that no damage will occur in the existing buildings and services at the surrounding area.

In this study, the excavation and advancement of tunnelling excavation in Tunnel TGV of Tartaiguille, France is modeled and analyzed using the numerical program in order to simulate the ground response due to the construction processes. On the other hand, CETU (Centre d'Etudes des Tunnels) had set out an instrumentation in sections of the tunnel in order to analyze the loading of the support of the tunnel and obtained the displacement of surrounding ground responses. The numerical simulation will take into account the visco plastic behavior of the soil. And then the result of numerical simulation will be compared to the field measurement data.

The constitutive model used in this study is an elasto-plastic constitutive model called CJS 2EC which has been developed by Ecole Centrale de Lyon. To lake into account the time-dependent behavior of the soil, the visco-plastic constitutive model has been embedded in the CJS 2EC model.

Hopefully with this study, we are getting one step ahead in estimating the ground responses in tunneling. The more realistic behavior of the soil around the tunnel, which include the time dependent behavior of the soil will be examined and gives an accurate prediction of ground response due to tunnelling excavation.

Observation of the results and comparison with the measurement data demonstrate that the time dependent behavior of soil cannot be neglected in the analysis of the tunnelling excavation."

"ABSTRACTThe development and extension of large cities creates a need of multiple shallow tunnels in the soft ground of built areas. Excavating a tunnel generates ground displacements and deformations which can affect existing buildings and services in urban sites and can lead to unacceptable damages. Prediction of the ground settlement caused by the tunnel excavation has been a major engineering challenge. A numerical simulation using finite element method was implemented in the aim of developing a procedure for forecasting the movement induced by tunneling. This study describes the modelling procedure, comparing one procedure in a complete stages of modelling (called phases modelling) taking into account different phases simulating the different kinds of interaction between the tunnel and the soil (deconfinement, lining installation, pore pressure applied on the lining, and weight of the lining) and one in a simple way called `deconfinement modeling', simulating the excavation using a stress decrease vector exerted on the excavation boundary in the opposite to the initial ground stress described by a scalar parameter A. (the deconfinement rate). A shallow lined tunnel is analyzed in a two dimensional analyses, and observations are made for the settlement at the surface and at the tunnel crown, the deformations of the tunnel opening, and the stress path around the tunnel. Comparison is conducted using two soil models : the Mohr-Coulomb model and the CJS model. Observations of the results and comparison with the experimental data demonstrate that the deconfinement modeling is adequate for the analyses of settlement induced by tunneling only if a good modeling of the soil behavior is considered."

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Adanya galian dan beban alat berat pada tanah lunak di sekitar tiang pancang menyebabkan pergerakan lateral tanah yang menghasilkan tekanan pasif pada fondasi tiang sehingga mengalami pergeseran. Penelitian ini bertujuan untuk menganalisis perilaku pergeseran tiang pancang pada studi kasus yang berlokasi di Gresik, Jawa Timur akibat pengaruh beban surcharge berupa alat berat dengan/tanpa adanya galian pada tanah lempung lunak. Perilaku pergeseran tiang disimulasikan menggunakan program aplikasi berbasis metode elemen hingga MIDAS GTS NX. Tiang pancang dimodelkan dengan menggunakan model konstitutif elastis dan elasto – plastis untuk mendapatkan hasil deformasi yang sesuai dengan kondisi aktual di lapangan. Sedangkan tanah dimodelkan dengan menggunakan model konstitutif tanah hardening soil untuk menggambarkan perilaku perubahan kekakuan pada tanah lempung. Analisis dilakukan untuk memeriksa kerusakan dan pergeseran lateral tiang pada kondisi lapangan serta pada skenario galian dan beban yang berbeda. Hasil analisis menunjukkan bahwa kondisi di lapangan dengan galian sedalam 0.8 m dan beban alat berat seberat 21.9 kN/m² yang bekerja sejauh 6 m dari tiang yang digali tidak menyebabkan tiang bergeser sesuai kondisi pergeseran aktual di lapangan. Pada analisis pengaruh tahap konstruksi galian dan beban alat berat, pola pergeseran lateral tiang cenderung meningkat secara linier seiring pertambahan kedalaman galian namun tidak meningkat secara linier seiring pertambahan jarak beban alat berat.

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Excavation and heavy equipment loads in soft soil around the pile cause lateral movement of the soil that produces passive pressure on the pile foundation so that it shifts.  This study aims to analyze the behavior of pile displacement in a case study located in Gresik, East Java due to the influence of surcharge loads in the form of heavy equipment with/without excavation in soft clay soil. The pile displacement behavior was simulated using a finite element method-based application program MIDAS GTS NX. The piles were modeled using elastic and elasto-plastic constitutive models to obtain deformation results in accordance with actual conditions in the field. The soil was modeled using a hardening soil constitutive model to illustrate the behavior of stiffness changes in clay soil. Analyses were conducted to examine the damage and lateral displacement of the piles under field conditions as well as under different excavation and load scenarios. The analysis showed that the field condition with 0.8 m deep excavation and 21.9 kN/m² heavy equipment load acting 6 m away from the excavated pile did not cause the pile to shift according to the actual shifting condition in the field. In the analysis of the effect of excavation construction stage and heavy equipment load, the lateral displacement pattern of the pile tends to increase linearly as the excavation depth increases but does not increase linearly as the distance of the heavy equipment load increases.

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"Indonesia mengembangkan teknologi terowongan dikarenakan banyaknya kontur pegunungan dan kondisi geologi yang kaya akan mineral, serta untuk mengatasi permasalahan kemacetan di kota-kota besar. Terowongan merupakan salah atu alternatif prasarana perhubungan masa depan yang memungkinkan untuk mempersingkat waktu perjalanan. Konstruksi terowongan sendiri merupakan jenis konstruksi yang kompleks dan membutuhkan kemampuan manajerial dan teknikal yang tinggi dalam pengerjaannya. Oleh karena itu, diperlukan perencanaan yang sangat baik dan detail pada setiap proyek terowongan. Tujuan dari penelitian ini adalah untuk menghasilkan kamus WBS dan checklist untuk konstruksi terowongan, sehingga dapat diidentifikasi faktor dominan apa saja yang berpengaruh pada kinerja K3. Penelitian ini terdiri dari beberapa tahap dengan metode kualitatif. Metodologi yang digunakan adalah validasi ahli, survei responden dan wawancara dan dianalisis menggunakan analisis deskriptif data modus. Dari penelitian ini, akan menghasilkan kamus WBS dan checklist dan faktor risiko dominan pada pekerjaan terowongan.

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Indonesia is developing the technology of tunnel construction because of many mineral problems, topography, and to overcome the problem of congestion in big cities. Tunnel is an alternative transportation infrastructure of the future that allows to shorten travel time. The tunnel construction itself consists of complex types of construction and requires high managerial and technical capabilities in the process. Therefore, good and detailed planning is needed for each tunnel project. The purpose of this study is to produce a WBS dictionary and checklist for tunnel construction, so as to identify what dominant factors are successful in K3 performance. This research consists of research with qualitative methods with the methodology used is expert validation, respondent surveys and interviews and analyzed using descriptive data mode analysis."