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"MRT Jakarta merupakan sebuah sistem transportasi modern yang sedang dibangun di Jakarta. Salah satu konstruksinya yaitu konstruksi bawah tanah menggunakan TBM tipe EPB sebagai metode pengerjaannya. Berdasarkan data histori dari konstruksi tunnel mencatat banyaknya permasalahan bahkan kegagalan dari konstruksi tunnel yang disebabkan oleh berbagai faktor dan dapat berdampak pada keterlambatan proyek. Suatu manajemen risiko diharapkan dapat mengurangi dampak buruk risiko yang dihadapi pada pekerjaan konstruksi. Penelitian berupa studi kasus menggunakan metode kuesioner pada tahap penggumpulan data. Pengolahan data yang dilakukan berupa analisis deskriptif, uji normalitas, uji validitas reliabilitas, uji homogenitas, dan analisis kualitatif risiko. Risk register merupakan output dari penelitian yang memberikan gambaran tingkat risiko, penyebab risiko, dan respon risiko yang dilakukan oleh kontraktor untuk mengurangi dampak risiko tersebut. Dalam penelitian ini terdapat 7 risiko dominan pada pekerjaan pengeboran tunnel yaitu Kerusakan segmen akibat tekanan mesin tinggi, Kesalahan koordinat posisi awal mesin TBM, Risiko yang terjadi akibat operator mesin tidak bersertifikat, Permukaan tanah menurun saat dilakukan pengeboran, Risiko mesin keluar dari center line , Ketersediaan segmen terlambat, dan Risiko kerusakan lapisan karet penahan tekanan air.

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MRT Jakarta is a modern transportasion system being executed in Jakarta. One of its construction is Underground Construction using TBM type of EPB as working methods. Based on historycal data of tunnel construction, there are many failure of tunnel occured by many factors and cause the project to delay. This research is case study using questionary and expert judgement method in phase of collecting data. The data provided is analized with descriptive analysis, normality test, validity and reliability test, homogenity test and qualitative risk analysis. Risk management is expected to decrease the effect of it.

Risk register is an output of this reseacrh determining level of hazard, cause of risk, preventive action, and risk respon by contractor to mitigate the hazard effect. Seven dominant riks as the result of this research are damaged to segment by high pressure of TBM, failure of TBM coordinate positioning, risk by uncertificate operator, Settlement of ground level when drilling, failure of TBM lining, Segments not available in timely manner, and Damage to the rubber coating retaining water pressure."

"The relationship between the Austrian tradition and Bloomington institutionalism has been part of a larger intellectual evolution of a family of schools of thought that coevolved in multiple streams over the last 100 years or so. The Bloomington scholars, once they delineated the broader parameters of their own research program, started to reconstruct, reinterpret, and in many cases simply rediscover and reinvent Austrian insights and themes. As such, they created the possibility of giving those insights and themes new interpretations and new applications, in novel circumstances with new research priorities, in particular, public administration, governance and collective action, and entrepreneurship in non-market settings."

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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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