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Abstrak :
ABSTRAK Poliol yang digunakan tersebut merupakan jenis poliol hidroksi metoksi yang diperoleh melalui reaksi epoksidasi, hidroksilasi dan metoksilasi, yang dikenal sebagai polio! HMGMS. Proses pembuatan foam poliuretan dilakukan dengan mereaksikan polioL HMGMS dengan MDI (4,4'-metilen difenil diisosianat) melalui metode one shoot process. Hasil penelitian menunjukkan karakterisasi poliol HMGMS didapat bilangan iod 8,92 mg 12/100 g dan bilangan hidroksi 122 mg KOH/ g sampel. Titik optimasi foam poliuretan perbandingan HMGMS dan MDI diperoleh pada perbandingan 1:3 dengan densitas foam sebesar 0,3026 g/ cm3. Pengaruh konsentrasi katalis (trietilen diamin) terhadap sifat struktur foam poliuretan menunjukkan dapat mempercepat pembentukan segmen keras lebih banyak, pengaruh konsentrasi surfaktan (silikon glikol) menunjukkan pembentukkan rongga sel "close coif' yang makin stabil dengan ukuran sel yang seragam, dan pengaruh konsentrasi pemanjang rantai (chain extender ) etilen glikol mempengaruhi pembentukan segmen lunak dengan memperpanjang rantai polimer. Didapatkan pula foam poliuretan yang semi rigid dari poliol HMGMS, sedangkan poliol PPG menghasilkan foam poliuretan yang fleksibel. Karakterisasi terhadap foam poliuretan dilakukan dengan menentukan densitas foam, kekerasan, analisa FTIR, dan SEM.

Abstrak :
Statics and dynamics of rigid bodies presents an interdisciplinary approach to mechanical engineering through a close evaluation of the statics and dynamics of rigid bodies, presenting a concise introduction to both. This volume bridges the gap of interdisciplinary published texts linking fields like mechatronics and robotics with multi-body dynamics in order to provide readers with a clear path to understanding numerous sub-fields of mechanical engineering. Three-dimensional kinematics, rigid bodies in planar spaces and numerous vector and matrix operations are presented in order to provide a comprehensive understanding of mechanics through dynamics and rigid bodies.

Abstrak :
This book contains a unique description of the nonholonomic motion of systems of rigid bodies by differential algebraic systems. Nonholonomic Motion of Rigid Mechanical Systems from a DAE Viewpoint focuses on rigid body systems subjected to kinematic constraints (constraints that depend on the velocities of the bodies, e.g., as they arise for nonholonomic motions) and discusses in detail how the equations of motion are developed. The authors show that such motions can be modeled in terms of differential algebraic equations (DAEs), provided only that the correct variables are introduced. Several issues are investigated in depth to provide a sound and complete justification of the DAE model. These issues include the development of a generalized Gauss principle of least constraint, a study of the effect of the failure of an important full-rank condition, and a precise characterization of the state spaces. In particular, when the mentioned full-rank condition is not satisfied, this book shows how a new set of equivalent constraints can be constructed in a completely intrinsic way, where, in general, these new constraints comply with the full-rank requirement. Several equivalent DAE formulations are discussed and analyzed thoroughly. The value of these DAE models rests upon the premise that they are more accessible than others to an effective numerical treatment. To substantiate this, a numerical algorithm is presented and numerical results for several standard problems are included to demonstrate the efficiency of this approach.

Abstrak :
ABSTRAK
Semakin berkembangnya teknologi. proses pemodelan dalam tiga dimensi saat ini menjadi jauh lebih mudah dari sebelumnya. Namun sebelum menganimasikan sebuah objek tiga dimensi memerlukan rigging secara manual untuk menentukan struktur kerangka internalnya. Peneliti akan melakukan eksperimen dengan beberapa skenario percobaan terhadap proses rigging untuk menghasilkan animasi kendaraan yang dinamis dengan memanfaatkan rigid body. Dalam hal ini implementasi rigid body pada rigging dilakukan karena rigid body sangat mirip dengan objek di dunia nyata. Memiliki gaya gravitasi dan gaya lainnya, seperti bisa bertumbukan dengan objek lain dan bisa saling mendorong antar objek. Secara khusus sistem rigging dengan mengimplementasikan rigid body pada model kendaraan tiga dimensi yang digunakan sebagai masukan akan menghasilkan rigging yang dapat digunakan untuk menciptakan massa dan gaya sehingga gerakan animasi kendaraan tiga dimensi lebih dinamis. Hasil penelitian ini menunjukkan bahwa Implementasi rigid body pada rigging model kendaraan tiga dimensi menghasilkan animasi yang dinamis karena rigid body dapat disimulasikan secara dinamis berkaitan dengan kontak dan tumbukan, serta objek yang dikendalikan secara dinamis merespon gerakan dan tumbukan dengan benda lain.

Abstrak :
[ABSTRAK
Adanya peningkatan KLB (Koefisien Lantai Bangunan) pada daerah padat di Jakarta, memungkinkan para pemilik gedung melakukan perluasan bangunan secara vertikal dengan menambah struktur baja di atas struktur beton bertulang eksisting. Seringkali sambungan rigid dipakai pada sambungan kolom dasar struktur baja di atas struktur beton dengan mengasumsikan terjadi hubungan menerus antara baja dengan beton. Pada kenyataanya asumsi ini belum tentu benar akibat dari kemampuan sambungan sesungguhnya yang terbatas oleh kapasitas dan kekakuannya. Sehingga asumsi tersebut perlu dievaluasi kebenarannya demi menjaga perilaku struktur dan sambungan. Untuk itu, penelitian ini melakukan evaluasi hasil perancangan sambungan rigid pada dasar kolom baja dengan memodelkan sambungan menjadi pegas yang menghubungkan struktur baja dan struktur beton. Kekakuan rotasi sambungan dimodelkan secara non-linier untuk mendapatkan perilaku pasca leleh dari analisis pushover. Kekakuan sambungan diperoleh dari konfigurasi sambungan hasil perancangan yang melibatkan nilai overstrength factor (Wo) sesuai ketentuan AISC 341. Pada penelitian ini terdapat 7 variasi kekakuan sambungan yang didasarkan variasi Wo pada kombinasi gaya-gaya di sambungan dan mutu angkur (Fu) pada nilai Wo tertentu. Hasil penelitian menunjukkan penurunan besarnya kekakuan sambungan akibat penurunan nilai Wo tidak mengurangi aksi sambungan rigid. Adanya variasi nilai Wo pada perancangan sambungan rigid tidak berpengaruh langsung nilai R dan Wo dari hasil pushover. Adanya variasi mutu angkur (Fu) juga tidak berpengaruh signifikan pada perilaku struktur. Hanya sambungan yang didesain dengan Wo = 1 menunjukkan perilaku non linier dan dimungkinkan terjadinya gagal geser. Untuk menjaga kekuatan di sambungan saat terjadi gempa di luar rencana pada struktur dan menjamin agar sambungan tetap berperilaku elastik, sambungan perlu didesain dengan menggunakan Wo minimal sebesar 1,5.

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ABSTRACT
An increase in Floor Area Ratio (KLB) in dense areas of Jakarta, enabling building owners to extend their building vertically by adding the steel frame structures above the existing reinforced concrete structures. A rigid connection of steel column bases above the concrete structures is often used by assuming a continous joint between steel and concrete. In the fact, this assumption is not necessarily true since the connection behaviour is limited to the capacity and stiffnesses. This may lead to evaluate the assumption so the overall structural and connection behaviour are controlled. Therefore, this research evaluates the rigid connection design by modeling the column base connections using spring connecting steel frame structures and concrete frame structures. The non linear rotational stiffness of the spring is modelled to obtain post yielding behavior from the pushover analysis. The connection stiffnesses are provided from connection designs involving overstrength factor (Wo) as prescribed in AISC 341. There are 7 connection stiffness variations are built in this research based on Wo variations on loading combinations and anchor grade variations (Fu) for certain value Wo. The results showed a decrease in connection stiffness due to reduction value of Wo independent to the connection rigidity actions. Variation of Wo in the rigid connection design has no direct impact on the value of R and Wo from pushover analysis. The anchor grade variations has no significant effect on the structural performance. The non linear behaviour and possibility of shear failure of the connections are happened only when using Wo = 1. The connections shall be designed by minimum Wo = 1,5 to ensure the connection strength and the connection behavior still remains elastically when a greater earthquake force is subjected to the structure;An increase in Floor Area Ratio (KLB) in dense areas of Jakarta, enabling building owners to extend their building vertically by adding the steel frame structures above the existing reinforced concrete structures. A rigid connection of steel column bases above the concrete structures is often used by assuming a continous joint between steel and concrete. In the fact, this assumption is not necessarily true since the connection behaviour is limited to the capacity and stiffnesses. This may lead to evaluate the assumption so the overall structural and connection behaviour are controlled. Therefore, this research evaluates the rigid connection design by modeling the column base connections using spring connecting steel frame structures and concrete frame structures. The non linear rotational stiffness of the spring is modelled to obtain post yielding behavior from the pushover analysis. The connection stiffnesses are provided from connection designs involving overstrength factor (Wo) as prescribed in AISC 341. There are 7 connection stiffness variations are built in this research based on Wo variations on loading combinations and anchor grade variations (Fu) for certain value Wo. The results showed a decrease in connection stiffness due to reduction value of Wo independent to the connection rigidity actions. Variation of Wo in the rigid connection design has no direct impact on the value of R and Wo from pushover analysis. The anchor grade variations has no significant effect on the structural performance. The non linear behaviour and possibility of shear failure of the connections are happened only when using Wo = 1. The connections shall be designed by minimum Wo = 1,5 to ensure the connection strength and the connection behavior still remains elastically when a greater earthquake force is subjected to the structure, An increase in Floor Area Ratio (KLB) in dense areas of Jakarta, enabling building owners to extend their building vertically by adding the steel frame structures above the existing reinforced concrete structures. A rigid connection of steel column bases above the concrete structures is often used by assuming a continous joint between steel and concrete. In the fact, this assumption is not necessarily true since the connection behaviour is limited to the capacity and stiffnesses. This may lead to evaluate the assumption so the overall structural and connection behaviour are controlled. Therefore, this research evaluates the rigid connection design by modeling the column base connections using spring connecting steel frame structures and concrete frame structures. The non linear rotational stiffness of the spring is modelled to obtain post yielding behavior from the pushover analysis. The connection stiffnesses are provided from connection designs involving overstrength factor (Wo) as prescribed in AISC 341. There are 7 connection stiffness variations are built in this research based on Wo variations on loading combinations and anchor grade variations (Fu) for certain value Wo. The results showed a decrease in connection stiffness due to reduction value of Wo independent to the connection rigidity actions. Variation of Wo in the rigid connection design has no direct impact on the value of R and Wo from pushover analysis. The anchor grade variations has no significant effect on the structural performance. The non linear behaviour and possibility of shear failure of the connections are happened only when using Wo = 1. The connections shall be designed by minimum Wo = 1,5 to ensure the connection strength and the connection behavior still remains elastically when a greater earthquake force is subjected to the structure]

Abstrak :
Pemerintah Provinsi Kalimantan Selatan menargetkan Bandara Syamsudin Noor Banjarmasin menjadi bandara international pada tahun 2014. Untuk mewujudkan hal itu diperlukan perencanaan pembangunan berbagai sektor, salah satunya adalah hanggar. Beberapa alternatif struktur baja sebagai pilihan jenis struktur atas yang bisa dipakai diantaranya yaitu struktur baja jenis flexible frame, rigid frame dengan perletakan jepit, serta rigid frame dengan perletakan sendi. Dalam penelitian ini dilakukan analisis perbandingan Rencana Anggaran Biaya (RAB) untuk ketiga jenis struktur tersebut. Dari hasil penelitian didapat bahwa struktur dengan jenis flexible frame merupakan alternatif dengan biaya terendah. ......Province Government of South Kalimantan targets Syamsudin Noor Airport Banjarmasin to be international airport in 2014. To achieve this, required the development planning on many sectors, one of them is the hangar. Several alternatives steel structure as the preferred type of structure on which can be used include the steel structure type flexible frame, rigid frame with placement flops, as well as the rigid frame with placement joints. In this study conducted a comparative analysis of Budget Plan for the three types of structures. The result is that the structure of the type of flexible frame is an alternative with the lowest cost.

Abstrak :
ABSTRAK
Penelitian ini membahas karakteristik dinamik dan respon seismik struktur jembatan box girder dengan variasi perletakan rigid, sendi dan fleksibel di atas pilar tinggi. Struktur dengan perletakan rigid dimodelkan sebagai struktur yang memiliki sambungan rigid (rigid) antara pilar dengan girder jembatan, sementara perletakan sendi tidak memiliki ketahanan terhadap momen (moment release) pada sambungannya. Perletakan fleksibel (elastomeric rubber bearing) dimodelkan sebagai elemen link yang menghubungkan girder jembatan dan pilar. Pada pemodelan, dilakukan variasi tinggi pilar jembatan, variasi jumlah bentang jembatan dan variasi penggunaan metode analisa gempa. Beban gempa menggunakan rekaman (time history) gempa chi-chi yang diskalakan sesuai dengan respon spektrum daerah Padang, Indonesia. Analisa gempa yang digunakan yaitu respon spektrum, time history linear dan time history nonlinear (Fast Nonlinear Analysis). Nonlinearitas didapat dari material elastomer yang berdeformasi melebihi batas lelehnya. Hasil analisis menunjukkan variasi pemodelan yang dilakukan berpengaruh terhadap periode getar, simpangan lateral dan gaya geser dasar serta gaya dalam jembatan. Periode getar dan simpangan lateral meningkat dari perletakan rigid, sendi ke fleksibel serta juga meningkat seiring bertambahnya ketinggian pilar. Bertambahnya jumlah bentang tidak terlalu berpengaruh pada periode getar. Gaya geser dasar dan gaya dalam pada jembatan dengan perletakan fleksibel lebih kecil dibanding penggunaan perletakan rigid maupun sendi, dan meningkat seiring kenaikan tingi pilar dan bertambahnya jumlah bentang. Analisa dengan respon spektrum paling konservatif karena menghasilkan gaya geser dasar yang paling besar, diikuti oleh analisa time history linear dan time history nonlinear. Analisa dengan respon spektrum juga menghasilkan simpangan lateral yang paling besar, sementara analisa time history linear menghasilkan simpangan lateral yang paling kecil.

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ABSTRACT
This study discusses the dynamic characteristic and the seismic response of box girder bridge structure with variation of rigid, pin, and flexible supports mounted on the top of long pier. Rigid support has the stiff connection between the top part of pier and the box girder. While structure with pin support has released moment at its connection. Flexible support using Elastomeric Rubber Bearing is modeled as link element connecting box girder and pier. Length of pier, number of span and eathquake analysis are to be variated. The earthquake load is time history Chi-chi earthquake, which is matched to response spectra of Padang, Indonesia. Response spectra, linear time history, and nonlinear time history (Fast Nonlinear Analysis) methods are used to analyze the structural response. Nonlinearity due to plastic deformation of elastomeric rubber bearing is applied. Result shows that variation undertaken affect the natural period, displacement and base shear of the bridge. Natural period and displacement increased from rigid, pin to flexible support, and also to increase with length of long pier, while the influence of the number of span is less significant. Base shear and inner force of the bridge with flexible support is smaller than other support, and also increase with length of long pier and number of span increase. Analysis of response spectra is the most conservative since it results largest base shear, followed by linear time history analysis and nonlinear time history analysis. It also shows largest displacement, while linear time history analysis shows smallest displacement.

Abstrak :
ABSTRAK
Sambungan antara kolom dan balok merupakan bagian dari struktur bangunan yang sangat rawan terjadi kegagalan karena pada bagian ini terjadi transfer gaya antara keduanya serta bagian yang berperilaku sebagai penghubung disipasi energi antarelemen yang disambung. Konsep sambungan semi-rigid telah dikembangkan sejak dulu, beberapa model analitis sambungan semi-rigid balok kolom telah diteliti untuk memodelkan respons atas getaran pada sambungan balok kolom dengan mempertimbangkan perilaku nonlinear di zona sambungan untuk mengatasi dampak dari deformasi geser dalam analisis struktural. Analisis yang digunakan untuk mengetahui keadaan zona panel pada sambungan balok kolom ini menggunakan analisis fiber model, yakni bentuk pemodelan numerik yang digunakan untuk memprediksi hasil dari eksperimen terhadap struktur. Pada skripsi ini, analisis fiber model dilaksanakan secara numerik dengan menggunakan program komputer Drain-2DX Dynamic Response Analysis of Inelastic-2 Dimension dengan versi 1.10. Variasi nodal dan elemen, kurva kuat tekan beton, kurva tegangan-regangan baja, serta pullout dan gap diberikan dalam pemodelan untuk mengetahui parameter yang mempengaruhi kesemi-rigid-an sambungan balok dengan kolom.

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ABSTRACT
Connection between the column and the beam is a part of the building structure which is very prone to accure failure because in this section there is a transfer of force between both of them as well as the part that behaves as a liaison of energy dissipation among the connected elements. The semi rigid connection concept has been developed since a long time ago, several analytical models of semi rigid beam column connections have been investigated to model the response of vibrations on beam column joints by considering nonlinear behavior in the connection zone to overcome the impact of shear deformation in structural analysis. The analysis used to determine the state of the panel zone on this beam column connection is a fiber model analysis, which is a numerical assessment used to predict the results of experiments on the structure. In this undergraduate thesis, fiber model analysis is performed numerically using Drain 2DX Dynamic Response Analysis of Inelastic 2 Dimension computer program with version 1.10. Nodal and elemental variations, concrete compressive curves, steel stress strain curves, and pullouts and gaps are given in modeling to determine the parameters affecting the rigidity of the beam columns joints.