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"Maraknya pembangunan infrastruktur di Indonesia tentu saja diiringi dengan harapan bahwa infrastruktur tersebut dapat dimanfaatkan dengan maksimal, sesuai dengan umur rencananya. Namun, tidak sedikit kasus kegagalan struktur terjadi pada beberapa proyek infrastruktur. Hal ini salah satunya disebabkan oleh minimnya implementasi pemantauan kesehatan struktur bangunan. Kurangnya pemantauan kesehatan struktur dapat menjadikan risiko kehilangan nilai suatu bangunan dan keselamatan penggunanya menjadi tinggi. Tingginya biaya pengadaan alat pemantauan dan terbatasnya anggaran pengelola/pemilik aset menjadi hal yang memberatkan untuk dapat melakukan pemantauan kesehatan struktur tersebut. Melalui penelitian ini, diharapkan bisa mendorong lahirnya alternatif teknologi yang dapat diandalkan dan lebih terjangkau dalam memantau kesehatan dan perilaku struktur bangunan. Penelitian dilakukan pada dua jenis benda uji, pelat besi (600mmx25.4mmx2.5mm) dan balok beton bertulang (3000mmx250mmx150mm), dengan membandingkan hasil pengukuran regangan pada uji lentur dan pengukuran natural frekuensi pada uji getar bebas menggunakan dua sistem alat monitoring, Arduino dan data-logger konvensional (NI). Kedua sistem alat monitoring tersebut dilengkapi dengan sensor percepatan (Kistler) & sensor regangan (TML). Penelitain ini diawali dengan melakukan pengamatan terhadap dua jenis koneksi pada sistem Arduino, I2C dan SPI, guna menentukan pengaturan yang akan digunakan. Koneksi SPI menunjukan kemampuan merekam data lebih tinggi dibanding I2C, dengan maksimum 2036 data/detik dan nilai deviasi standar 0.028g. Hasil monitoring regangan pada uji lentur pelat besi menunjukan pola yang serupa antara Arduino, NI, dan nilai teoritis. Pada uji getar bebas, hasil dari penelitian ini menunjukan bahwa nilai natural frekuensi yang diperoleh dari hasil analisis FFT data percepatan yang didapatkan dari Arduino (ADXL345) dan NI (Kistler) menunjukan pola yang serupa. Relative error pada mode 1 & 2 berkisar antara 0.6% - 4.8% dan pada mode 3 menunjukan relative error antara 2.4% - 17.2%. Pada benda uji pelat besi, nilai relative error mode 1 terhadap analisis teoritis adalah 0.396%.

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Massive infrastructure development in Indonesia is definitely accompanied by the hope that the infrastructure can be utilized optimally, in accordance with the design lifetime. However, quite a number of structural failure cases have occurred in several infrastructure projects. Lack of structural health monitoring system (SHMS) is one of the causes which makes the risk of building collapse and safety issue is increased. The high cost of equipment procurement and the limited budget of the project are the factors that mainly caused the implementation of SHMS challenging. This research is expected to encourage the emergence of reliable and more affordable SHMS technologies. The study was conducted on two types of specimens, steel plates (600mmx25.4mmx2.5mm) and reinforced concrete beam (3000mmx250mmx150mm). It compared the results of strain measurements in the bending test and natural frequency measurements in the free vibration test using two monitoring tool systems, Arduino and data logger (NI) equipped with accelerometer (Kistler) & strain gauge (TML). The research begins by observing two types of connections on the Arduino system, I2C and SPI, to determine the settings to be used. SPI connection shows higher sampling rate than I2C, with a maximum of 2036 data/second and standard deviation is 0.028g. Strain measurements in the steel plate bending test showed a similar pattern between Arduino, NI, and theoretical values. In the free vibration test, the natural frequency value from the FTT analysis of acceleration data for the two systems has a similar pattern. The relative error in modes 1 and 2 ranges from 0.6-4.8%, while in mode 3 it ranges from 2.4-17.2%. On the steel plate test specimen, the relative error mode 1 value to the theoretical analysis is 0.396%."

"Kesuksesan suatu lapangan geotermal sangat ditentukan dari kegiatan eksplorasi untuk menentukan model konseptual geotermal, sehingga dapat diketahui lokasi sumur pemboran yang tepat. Studi pendahuluan dan pemboran pada tahap eksplorasi di lapangan panasbumi “X” telah dilakukan oleh PT. PLN Geothermal. Sumur WE-1 dibor pada tahun 2010-2011 sampai kedalaman 932.67 m namun temperatur stabil sumur sampai saat ini belum diketahui secara pasti. Permasalahan tersebut kemungkinan dikarenakan suhu dibawah permukaan yang telah "mendingin" atau tidak ada permeabilitas, dimana permeabilitas berhubungan dengan struktur geologi. Oleh karena itu penelitian ini dilakukan untuk memastikan keberadaan struktur bawah-permukaan dan zona reservoir dengan menggunakan teknologi remote sensing dan data magnetotellurik. Dalam penelitian ini, dilakukan penarikan kelurusan berdasarkan remote sensing untuk mengetahui struktur geologi permukaan, sedangkan pencitraan struktur di bawah-permukaan didapatkan melalui analisis pola splitting kurva, serta dengan melihat hasil inversi 3-dimensi magnetotellurik, daerah reservoir diketahui dari batas Base of Conductor. Hasil analisis geokimia digunakan untuk menentukan perkiraan temperatur reservoir, sehingga dapat membantu dalam pembuatan model konseptual dan deliniasi daerah prospek. Konseptual model daerah penelitian menggambarkan sumber panas berasal dari Gunung Eriwakang yang menjadi zona upflow yang dikontrol oleh sesar Banda dan Sesar Banda- Hatuasa. Direkomendasikan 1 sumur eksplorasi sebagai rekomendasi awal pemboran yang ditempatkan diantara sesar Banda dan sesar Banda-Hatuasa yang kemungkinan menjadi prospek permeabilitas.

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The success of a geothermal field is determined by exploration activities, to establish the geothermal conceptual model. Therefore, the exact location of drilling wells could be provided. Preliminary survey and drilling in the exploration stage at the geothermal field “X” had been done by PT. PLN Geothermal. WE-1 well was drilled in 2010-2011 to 932.67 m of depth. Unfortunately, the stable well’s temperature has not confirmed for certain until now. The issue is likely due to the subsurface temperature has been cooled down or no permeability, the permeability most likely associated with the structural geology. Therefore, this study was conducted to confirm the presence of subsurface structures and reservoir zone using remote sensing technology and magnetotelluric data.

In this study, the lineament was drawn based on remote sensing data to determine the surface geological structure. While the image of the subsurface structure is obtained by analyzing the pattern of the splitting curve, as well as to see the results of the 3-dimensional magnetotelluric inversion, the reservoir was interpreted by the boundary of BOC (Base of Conductor). Geochemical analysis results are used to determine the approximate temperature of the reservoir, to make the conceptual model and the delineation of the prospect area. The conceptual model of the study area illustrates the heat sources comes from Mt. Eriwakang, as the upflow zone which controlled by Banda fault and Banda-Hatuasa fault. As the initial drilling, one well is recommended to be drilled which is locate between Banda fault and Banda-Hatuasa fault. It is likely to have the prospect of permeability."

"This book presents extensive information on structural health monitoring for suspension bridges. During the past two decades, there have been significant advances in the sensing technologies employed in long-span bridge health monitoring. However, interpretation of the massive monitoring data is still lagging behind. This book establishes a series of measurement interpretation frameworks that focus on bridge site environmental conditions, and global and local responses of suspension bridges. Using the proposed frameworks, it subsequently offers new insights into the structural behaviors of long-span suspension bridges. As a valuable resource for researchers, scientists and engineers in the field of bridge structural health monitoring, it provides essential information, methods, and practical algorithms that can facilitate in-service bridge performance assessments."

"Sensors are used for civil infrastructure performance assessment and health monitoring, and have evolved significantly through developments in materials and methodologies. Sensor technologies for civil infrastructure Volume I provides an overview of sensor hardware and its use in data collection.The first chapters provide an introduction to sensing for structural performance assessment and health monitoring, and an overview of commonly used sensors and their data acquisition systems. Further chapters address different types of sensor including piezoelectric transducers, fiber optic sensors, acoustic emission sensors, and electromagnetic sensors, and the use of these sensors for assessing and monitoring civil infrastructures. Developments in technologies applied to civil infrastructure performance assessment are also discussed, including radar technology, micro-electro-mechanical systems (MEMS) and nanotechnology."

"ABSTRAKDalam kehidupan sehari-hari, temperatur jarang diperhitungkan dalam proses perancangan dan pemantauan struktur, dimana mayoritas insinyur dan praktisi menitikberatkan proses desain pada pembebanan gravitasi dan lateral, seperti gempa dan angin. Padahal, pada kasus-kasus tertentu, temperature bisa menjadi faktor penentu pada struktur, secara khusus pada jembatan bentang panjang. Terlebih lagi, statistik menunjukan bahwa temperatur di muka bumi cenderung terus meningkat, sehingga dapat mengakibatkan pula besarnya dampak yang ditimbulkan akibat perubahan temperatur ini, dan dapat menyebabkan perubahan parameter-parameter struktur, salah satunya adalah parameter dinamik, seperti frekuensi natural dan mode shape, yang akan menjadi fokus penelitian ini. Parameter dinamik dipilih karena memiliki hubungan langsung dengan parameter fisik, yaitu massa dan kekakuan struktur. Sehingga, saat parameter fisik mengalami perubahan, parameter dinamik juga akan segera mengalami perubahan. Perubahan ini juga cenderung dapat menurunkan kinerja struktur, dan menyebabkan perbedaan karakteristik struktur. Dalam peraturan, dijelaskan bahwa struktur diizinkan untuk memiliki nilai simpangan parameter sampai dengan 10 dari kondisi ideal untuk dapat dikategorikan sebagai struktur yang sehar. Oleh karena itu, penelitian ini bertujuan untuk mengobservasi pengaruh temperatur terhadap perubahan parameter struktur, dengan menjadikan salah satu jembatan busur dengan perletakan sendi di Bangkinang, Riau, Indonesia sebagai objek studi kasus. Penelitian dilakukan dengan memodelkan struktur dengan prinsip finite element secara 3D, pemodelan matematis secara 2D, dan pengujian getaran langsung di lapangan. Dari penelitian ini didapati perbedaan temperatur dapat menyebabkan simpangan frekuensi natural struktur sebesar 3.63 .

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ABSTRACTSeldom is temperature change effect taken into account in structural design and monitoring, since many engineers are focusing only on gravitational and lateral forces, such as wind and earthquake loadings. However, in some cases temperature may be the governing load case in design and monitoring process, especially for a long span bridge. Moreover, statistics have shown that the world rsquo s temperature is gradually increasing nowadays, which means the range of the temperature is raising up. As the range of temperature increases, the resulting temperature effect will also increase. This may cause an alteration to some parameters of the structure, such as dynamics parameters, which will be a focusing object in this research. These parameters are directly corelated to physical parameters, e.g. mass and stiffness. Hence, as the physical parameters has any kind of change, dynamic parameters will also definitely change. This alteration may decrease the health index of the structure. In some regulations, the deviation of the value of natural frequencies, as one of dynamics characteristics, is limited as 10 . This study is intended to observe the health index of the case study bridge and to observe the effect of temperature to dynamics performance of a pinned supports arch bridge in the Province of Riau, Indonesia, and it was found, by modeling the structure in Finite Element FE Model and performing vibration testing, that temperature difference has caused the natural frequencies of the bridge to vary up to 3.63 . "