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"This book examines current issues of fiber reinforced polymer (FRP) composites in civil infrastructure. The contents of this book are divided into two parts. The first part engages topics related to durability and service life of FRP composites and how they contribute to sustainability. The second part highlights implementation and applications of the FRP composites with an emphasis on bridge structures. An introductory chapter provides an overview of FRP composites and its role in a sustainable built environment highlighting the issues of durability and service life followed by a current review of sustainability in infrastructure design.​"

"The use of fiber-reinforced polymer (FRP) composite materials has had a dramatic impact on civil engineering techniques over the past three decades. FRPs are an ideal material for structural applications where high strength-to-weight and stiffness-to-weight ratios are required. Developments in fiber-reinforced polymer (FRP) composites for civil engineering outlines the latest developments in fiber-reinforced polymer (FRP) composites and their applications in civil engineering.Part one outlines the general developments of fiber-reinforced polymer (FRP) use, reviewing recent advancements in the design and processing techniques of composite materials. Part two outlines particular types of fiber-reinforced polymers and covers their use in a wide range of civil engineering and structural applications, including their use in disaster-resistant buildings, strengthening steel structures and bridge superstructures."

"Performance-based design (PBD) untuk struktur bawah belum diperbolehkan di Indonesia karena terdapat syarat yang harus dipenuhi, yaitu limited ductility dan repairable. Definisi dari repairable sendiri belum dijelaskan secara detail sehingga diperlukan penelitian lebih lanjut mengenai maknanya. Penelitian perbaikan dilakukan terhadap benda uji sambungan spun pile terhadap pile cap yang sudah rusak parah dan diperbaiki menggunakan fiber reinforced polymer (FRP) berupa FRP rod dan FRP wrap. Pengujian dilakukan untuk spun pile dengan beton pengisi yang diperbaiki dengan sepuluh buah FRP rod dan dua lapis FRP wrap. Parameter yang dilihat dalam menentukan perilaku dan efektivitas perbaikan adalah kekuatan, daktilitas, energi disipasi, momen rotasi, degradasi kekakuan, dan degradasi kekuatan. Hasil penelitian menunjukan bahwa benda uji mampu kembali ke kondisi awal dengan adanya penurunan kekuatan. Damage index dan performance levels juga dianalisa untuk eksperimen dan setiap model yang dibuat. Berdasarkan hal tersebut, dapat diketahui bahwa jumlah FRP rod yang digunakan dan kondisi awal benda uji sebelum perbaikan akan mempengaruhi efektivitas perbaikan yang dilakukan. Model dengan kondisi awal sebelum perbaikan berupa serviceable dan repairable berdasarkan damage index, memberikan perbaikan yang paling efektif untuk kembali ke kondisi awal sambungan spun pile terhadap pile cap sebelum mengalami kerusakan.

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Performance-based design (PBD) is not allowed for lower structures in Indonesia because there are conditions that must be met, namely limited ductility and repairability. The definition of repairable itself has not been explained in detail so further research is needed on its meaning. Repair research was carried out on test specimens for spun pile connections to pile caps that were severely damaged and repaired using fiber reinforced polymer (FRP) in the form of FRP rods and FRP wrap. Tests were carried out for spun piles with infill concrete repaired with ten FRP rods and two layers of FRP wrap. Parameters considered in determining the behavior and effectiveness of repairs are strength, ductility, energy dissipation, rotational moment, stiffness degradation, and strength degradation. The results showed that the test object was able to return to its initial condition with a decrease in strength. Damage index and performance levels were also analyzed for the experiment and each model was created. Based on this, it can be seen that the number of FRP rods used and the initial condition of the test object before a repair will affect the effectiveness of the repairs carried out. The model with the initial conditions before repair in the form of serviceable and repairable based on the damage index provides the most effective repair to return to the initial condition of the spun pile-pile cap connection before it was damaged"

"Analisis yang dilakukan terhadap fondasi di Indonesia masih berada di tahap linear elastis dan batas displacement yang disyaratkan oleh SNI 8460:2017 hanya sebesar 12 mm untuk kondisi gempa rencana dan 25 mm untuk kondisi gempa ekstrem pada kondisi free-head. Akibatnya, diperlukan jumlah dan ukuran fondasi yang besar supaya fondasi tetap berperilaku elastis dan tidak terjadi kegagalan sama sekali. Namun, kenyataannya kerusakan pada fondasi tidak dapat dihindari jika terjadi gempa ekstrem. Potensi kerusakan fondasi pada bangunan di Indonesia menjadi semakin besar akibat terjadinya peningkatan percepatan gempa pada tahun 2017 silam sehingga nantinya desain fondasi akan menjadi semakin besar untuk dapat memenuhi persyaratan deformasi izin lateral tiang. Di sisi lain, struktur atas telah menerapkan konsep performance-based design yang mengizinkan terjadinya kerusakan pada balok di area yang mudah diperbaiki. Penggunaan konsep performance-based design pada struktur bawah masih dalam tahap penelitian mengingat sulitnya proses perbaikan pada fondasi. Oleh karena itu, dilakukan uji eksperimen pada spun pile berdiameter 450 mm yang telah mengalami kerusakan akibat pembebanan siklik arah lateral kemudian diperbaiki menggunakan fiber reinforced polymer (FRP) lalu diuji kembali. Hasil eksperimen menunjukkan bahwa penggunaan Sika Carbodur 512 (FRP Plate) dan Sika Wrap 231C (FRP Wrap) mampu memulihkan kapasitas benda uji dengan perilaku struktur yang kurang lebih sama, bahkan ketika terjadi kegagalan debonding pada FRP Plate. Perilaku FRP yang sangat elastis memberikan banyak keunggulan pada drift awal hingga menuju drift akhir, khususnya pada failure mode serta degradasi kekuatan. Bahkan, kapasitas lateral fondasi yang diperbaiki menggunakan FRP mampu pulih sebesar 68-97% dari kapasitas awal sebelum perbaikan. Namun, pada drift yang sangat besar, terjadi kegagalan pada FRP plate dan pile cap sehingga terjadi penurunan kekuatan dan kekakuan yang sangat tinggi. Hal ini dapat diatasi dengan memberikan tulangan pengisi sehingga fondasi masih memiliki cadangan kekuatan dan mampu berdeformasi secara inelastis. Tulangan pengisi juga memberikan berkontribusi yang besar terhadap perilaku pinching. Namun, berdasarkan perhitungan, daktilitas dan energi disipasi benda uji yang telah diperbaiki relatif lebih kecil daripada benda uji sebelum perbaikan.

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Study of spun pile and its connection has not attracted such a considerable amount of research in Indonesia since the design code is still based on the elastic concept. Lateral displacement of pile is restricted to 12 mm for the earthquake design load and 25 mm for severe earthquakes for single-pile with free-head condition, in order to maintain the elastic condition and avoid any damages in pile. In fact, many foundations were damaged after severe earthquake. This inevitable failure could be worse due to increase of seismic demand in Indonesia and thus leads to the larger size of foundation in order to meet the requirements of strength and displacement. Meanwhile, design of upper structure has overcome the problem by implementing performance-based design which allows plastic hinge in some repairable areas, such as beam-end support. The research of performancebased design in foundation is still ongoing due to the difficulty of the repair process. Therefore, an experimental study was conducted on 450 mm diameter spun pile which has been tested against lateral cyclic loading then repaired using fiber reinforced polymer (FRP) and the lateral cyclic loading was conducted again. Experimental results show that the application of Sika Carbodur 512 (FRP Plate) and Sika Wrap 231C (FRP Wrap) can restore the foundation capacity along with the better structure behavior compared with the initial condition before repair occurred. Elastic behavior of FRP provides many advantages at early drift, especially the failure mode and strength degradation. Lateral capacity of the foundation repaired using FRP is able to recover by 68-97% of the initial capacity before repair occurred. However, at the very large drift, occurrence of flexural failure of FRP plate and debonding failure of pile cap increase the stiffness and strength degradation rapidly. This problem can be overcome by providing reinforcement on concrete infill as the residual capacity so that the foundation could undergo large displacement with minimum degradation. Reinforcement of the concrete infill can also reduce the pinching behavior. However, ductility and energy dissipation of the repaired foundation is smaller than the one before repair occurred."

"Optical microscopy is one of the most valuable?but under utilized?tools for analyzing fiber reinforced polymer matrix composites. This hands-on instructional book covers everything; sample preparation, microscopic techniques, and applications. The power of optical microscopy to study the microstructure of these heterogeneous, anisotropic materials is illustrated with over 180 full color images."

"Advanced fibre-reinforced polymer (FRP) composites have become essential materials for the building of new structures and for the repair of existing infrastructure. Advanced fibre-reinforced polymer (FRP) composites for structural applications provides an overview of different advanced FRP composites and the use of these materials in a variety of application areas.Part one introduces materials used in the creation of advanced FRP composites including polyester, vinylester and epoxy resins. Part two goes on to explore the processing and fabrication of advanced FRP composites and includes chapters on prepreg processing and filament winding processes. Part three highlights properties of advanced FRP composites and explores how performance can be managed and tested. Applications of advanced FRP composites, including bridge engineering, pipe rehabilitation in the oil and gas industry and sustainable energy production, are discussed in part four."

"Komposit hijau merupakan komposit yang salah satu bahan penyusunnya terdiri dari bahan ramah lingkungan. Salah satunya menggunakan serat alam sebagai penguat. Salah satu jenis serat alam yang sering digunakan adalah kenaf. Penelitian ini bertujuan untuk mendapatkan pemodelan sifat elastis komposit berpenguat serat kenaf Sumberejo dengan berbagai variasi matriks polimer. Variasi matriks polimer yang digunakan adalah polipropilena, poli asam laktat, epoksi dan poliester. Pemodelan komposit ini menggunakan teori Rule of mixture dan teori lamina yaitu specially orthotropic. Hasil penelitian menunjukkan bahwa komposit epoksi/ serat kenaf Sumberejo memiliki regangan yang lebih rendah dibandingkan dengan tiga matriks polimer lainnya yaitu sebesar 0,61% untuk longitudinal dan 0,90% untuk transversal. Namun, komposit epoksi/ serat kenaf Sumberejo memiliki modulus elastisitas yang lebih tinggi dibandingkan dengan tiga matriks polimer lainnya yaitu sebesar 9174 MPa untuk longitudinal dan 6639 MPa untuk transversal. Pemodelan sifat elastis komposit pada penelitian ini menunjukkan bahwa komposit epoksi/ serat kenaf Sumberejo memliki sifat mekanik terbaik dibandingkan komposit berpenguat serat kenaf dengan matriks tiga polimer lainnya.

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Green composite is a composite of which one of the constituent materials consists of environmentally friendly materials. One of them uses natural fiber as a reinforcement. One type of natural fiber that is often used is kenaf. This study aimed to obtain an elastic property model of Sumberejo kenaf fiber reinforced composites with a variety of polymer matrix variations. Polymer matrix variations used were polypropylene, polylactic acid, epoxy, and polyester. Rule of mixture and specially orthotropic lamina theories were applied to these composite models. The results of the study indicated that the epoxy/ Sumberejo kenaf fiber composite had lower strain compared to other three polymer matrices with the result of 0,61% for the longitudinal and 0,90% for the transverse. However, the epoxy/ Sumberejo kenaf fiber composite had higher elasticity modulus compared to the other three polymer matrices with the result of 9174 MPa and 6639 MPa for longitudinal and transverse directions respectively. The elastic property modeling from this study indicated that epoxy reinforced Sumberejo kenaf fiber composites had the best mechanical properties compared to the other three polymers reinforced Sumberejo kenaf fiber composites."

"High Performance Fiber Reinforced Cement Composites (HPFRCC) represent a class of cement composites whose stress-strain response in tension undergoes strain hardening behaviour accompanied by multiple cracking, leading to a high strain prior to failure. The primary objective of this International Workshop was to provide a compendium of up-to-date information on the most recent developments and research advances in the field of HPFRCC. Approximately 65 contributions from leading world experts are assembled in these proceedings and provide an authoritative perspective on the subject. Special topics include fresh and hardening state properties, self-compacting mixtures, mechanical behavior under compressive, tensile, and shear loading, structural applications, impact, earthquake and fire resistance, durability issues, ultra-high performance fiber reinforced concrete, and textile reinforced concrete. "