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"Tesis ini membahas pemodelan numerik untuk perilaku interface terhadap beban monotonik (geser). Analisis dilakukan dengan menggunakan model Direct Shear Test oleh karena kemudahannya. Pemodelan numerik dilakukan dengan menggunakan program Fast Lagrangian of Continua (FLAC) Code. Model konstitutif interface yang dipakai adalah Modifikasi Mohr Coulomb dengan Fungsi Hiperbolik. Secara umum, model ini dapat mensimulasi perilaku interface terhadap beban geser. Pada kasus pasir padat (dense), interface mengalami kontraktansi diikuti dengan dilatansi. Untuk pasir lepas (loose), interface hanya mengalami kontraktansi saja selama pembebanan geser. Untuk memodelkan kontraktansi dan dilatansi pada interface digunakan Hukum Dilatansi. Kajian lebih lanjut menyimpulkan bahwa pada kondisi batas yang berbeda, maka plastisitas pada CNV muncul terlebih dahulu kemudian diikuti dengan CNS kemudian CNL. Munculnya pola deformasi berbentuk lenticular juga terlihat pada zona interface setelah pembebanan geser. Studi aplikasi pada tiang pancang menggarisbawahi bahwa asumsi untuk properti interface tentunya akan mempengaruhi perilaku sistem tiang pancang.

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This thesis presents a numerical model to study the behavior of the interface under monotonic loadings (shearing). The Direct Shear Model was used in the analysis because of its simplicity. The numerical model was performed by using Fast Lagrangian of Continua (FLAC) Code. The interface model used here is the Modified Mohr Coulomb Model with a hyperbolic Law. In general, this model is sufficient to simulate the interface behavior. Under shearing, the interface exhibits contractancy followed by dilatancy in the case of dense sand. For the loose sand case, the interface experience contractancy throughout shearing. The generation of contractancy and dilatancy was created by using a simple dilatancy law. A further study with different boundary condition outlined that the yielding state in CNV test starts at the very beginning, then followed by the CNS and the CNL test. The occurence of a lenticular shape was also observed in this study. This explains the deformation shape of the interface zone after shearing. An application to a pile foundation system outlined that the interface strength and the density of the soil influence the pile responses."

"Horizontal shear interaction between profiled steel sheeting and concrete in composite slab is obtained through various means, such as frictional resistance due to indentation or embossment in the sheeting, interlocking at the steel and concrete interface resulting from curvature and shape of the sheeting profile under bending, and anchorage devices such as welded shear studs and crippled sheeting at the end of the span. Permanent end pour stops may provide some restraining effect to the slipping of the concrete, and hence may enhance the composite action. Despite the use of many types of devices, most reported test results of typical length composite slabs still exhibit partial shear interaction. This paper reports the enhancement of the horizontal shear interaction at the concrete-profiled steel sheeting interface of composite slab by using shear screws. Six full scale bending tests were conducted of which three specimens with different slenderness were enhanced with self drilling screws while another three were without screws. The test results show that the failure mode of composite slab can be improved to ductile type and the load carrying capacity can be increased by the presence of the shear screws. The load performance of the slab is also affected by the slenderness, which is the ratio of shear span to effective depth."

"Pencampuran enzim urease dan larutan penjenuh berupa urea dan kalsium klorida pada tanah pasir merupakan salah satu proses biogrouting yang merubah bentuk butiran pasir menjadi batuan pasir. Permasalahan dalam penelitian ini adalah seberapa besar pengaruh perubahan bentuk pasir terhadap parameter kuat geser pasir tersebut. Parameter kuat geser pasir berupa kohesi dan sudut geser. Uji direct shear dilakukan sesuai standar ASTM D 3080-03 untuk mendapatkan nilai kohesi dan sudut geser dari tanah pasir. Setelah transformasi butiran pasir menjadi batuan pasir terjadi, didapatkan hasil berupa kenaikan nilai kohesi yang menunjukkan ikatan partikel pasir yang semakin kuat. Pasir kontrol tanpa perlakuan pada penelitian ini memiliki kohesi sebesar 0 kPa dengan sudut geser 32,72 °, pasir yang telah tersementasi dan didiamkan selama 7 hari memiliki kohesi sebesar 317,01 kPa dengan sudut geser 33,27 ° , sedangkan pasir yang tersementasi dan didiamkan selama 14 hari memiliki kohesi sebesar 788,78 kPa dengan sudut geser 36,11 °.

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Adding enzym urease and cementation solution which consists of urea and calcium chloride is one of biogrouting process which transform particle of sand to become sandstone. Main topic on this paper is how big the effect of these transformation of sandstone in aspect to shear strength parameter on sand soil. Shear strength parameter consists of cohesion and friction angle of sand soil. Direct shear test is performed to follow ASTM D 3080-03. After the transformation done and formed the sandstone, increase in shear strength parameters are achieved. Control sands on this paper have 0 kPa cohesion value and friction angle of 32,72°. Sandstones with 7 days fermentation have cohesion value of 317,01 kPa with friction angle of 33,27°. Sandstones with 14 days fermentation have cohesion value of 788,78 kPa with friction angle of 36,11°"

"Several studies have already been published in order to better understand the behaviour of interfaces. Different experimental methods, including direct shear tests, simple shear test, and tortional ring test, and also various constitutive models were presented to modelize the behaviour of the interface. These studies revealed that the main factors that affect the behaviour of the interface include the roughness of the interface, the soil mineralogy, the soil density, and the normal stress applied. This work was therefore directed primarily to better understand the overall behaviour of the interface and the influence of these factors in a monotonic and cyclical solicitation. Through the simulation of a direct shear test at constant normal stress (CNL) in FLAC 5.0, several typical behaviours, including degradation of shearing resistance and contractancydilatancy, have been observed and modelled. At first, the law of Mohr-Coulomb and its correspondent failure criterion have been implemented. Then several models have been proposed to model more precisely the behaviour. Finally, two cyclicals laws, the law of Ramberg-Osgood law and Byrne, originally developed for the soil, have been implemented in this model. This study has verified the consistency of the results and has determined whether the injection of such laws is sufficient to modelize the behaviour of the interface under cyclic loading. "

"Estimasi kecepatan gelombang seismik shear (Vs) pada suatu log sumur menjadi kunci keberhasilan Studi pada lapangan yang tidak memiliki log Vs. Untuk itu pemahaman sifat Hsika batuan menjadi syarat utama dalam estimasi Vs. Pada Tugas Akhir (TA) ini dilakukan estimasi kecepatan gelombang seismik S dan aplikasinya untuk pemodelan penggantian fluida pada suatu reservoar. Estimasi Vs dilakukan dengan beberapa algoritma yaitu hubungan empiris, Castagna, Gassmann dan Xu-White.Hasil estimasi dari algoritma-algoritma tersebut memperlihatkan bahwa algoritma Xu-White memberikan hasil yang lebih tepat dibandingkan dengan beberapa metode lain. Hasil ini dapat dipahami karena Xu- White dalam perhitungannya memperhatikan faktor matrik batuan.

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Shear Wave estimation on the well log, which has no S-sonic log, become succesful key in the reservoir characterization. Therefore, the knowledge of petrophysical properties becomes the main prerequisite for estimating Vs. In this study, shear Wave estimation is performed and the estimated shear Wave is used to carry out Fluid Replacement Modeling. A number of algorithm is used to estimate the S Wave such as empirical relationship, Castagna, Gassmann and Xu-White.

The result shows that Xu-White algorithm, provide more accurate results compare to the other algorithms. This conclusion can be understood since the Xu-White algorithm consider the matrix of rock."

"An adoption of body-worn cameras by police institutions would need a sufficient preliminary study. This article aims to provide a literature review for police managers in considering their decision to implement body-worn cameras on field officers. The use of body-worn cameras have yield mixed results from police institutions worldwide. Cameras, in theory, would serve as an accountability measure in making sure that procedures are being followed. On the other hand, the presence of a camera may limit discretionary action and slow down an officer’s decision-making. Evidences from previous research showed that BWCs promotes behavioral change, but their direct effectiveness in reducing public complaints remain arguable. It is then proposed that police institutions should carefully consider their policies regarding the implementation of BWCs due to their high cost and debatable efficacy."

"Penelitian ini membahas mengenai perilaku struktur dinding geser beton bertulang dan dinding geser pelat baja dengan analisis statik non-linier pushover akibat beban gempa. Pada penelitian ini ditinjau bangunan 12 lantai pada lokasi gempa di Jakarta, tanah lunak dan dianalisis berdasarkan peraturan SNI 03-1726-201x. Analisis pada struktur dinding geser beton menggunakan SAP2000 dan pada struktur baja menggunakan ETABS v9. Penentuan tingkat kinerja menggunakan metode spektrum kapasitas yang mengacu pada ATC 40. Hasil analisis menunjukkan bahwa model struktur dinding geser pelat baja memiliki kinerja struktur yang lebih baik dibandingkan dengan struktur dinding geser beton bertulang.

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This thesis discussed about behavior of reinforced concrete shear wall and steel plate shear wall using static non-linear pushover analysis due to earthquake load. In this thesis, 12-story building with earthquake location in Jakarta with soft soil is considered and analyzed based on Indonesia Building Code SNI 03-1726-201x. Reinforced concrete shear wall is analyzed by SAP 2000 and steel plate shear wall is analyzed by ETABS v.9. Determination of performance level use spectrum capacity method based on ATC 40. Analysis results show that steel plate shear wall has a better performance level than reinforced concrete shear wall."