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Abstrak :
Pada saat ini beton siap pakai (ready mix) sedang marak digunakan untuk membuat konstruksi bangunan, namun pada penerapannya sering terjadi kelebihan supply dan sisanya terkadang dibuang di sembarang tempat, sehingga dapat mengurangi kesuburan tanah dan merusak keseimbangan ekosistem. Salah satu cara untuk mengatasinya adalah mendaur ulang limbah beton. Namun, pemanfaatan limbah sebagai agregat daur ulang tersebut perlu dikaji lebih mendalam, dengan melakukan pengujian secara eksperimental dan analisis terhadap karakteristik yang dimiliki. Metoda dan prosedur pelaksanaan pengujian agregat daur ulang tersebut dilakukan dengan mengacu pada standar ASTM. Beton dibuat dengan agregat alam maupun campuran antara agregat alam dan agregat daur ulang dengan komposisi tertentu. Kekuatan beton yang akan dipakai adalah 25 MPa. Kemudian dilakukan pengujian terhadap kuat lentur pada umur 28 hari dan susut selama 56 hari. Berdasarkan hasil studi eksperimental, agregat daur ulang mengandung mortar. Kandungan mortar tersebut mengakibatkan absorpsi agregat menjadi lebih besar, lebih poros atau berpori, sehingga kekerasannya berkurang. Beberapa perbedaan kualitas, sifat-sifat fisik dan kimia agregat daur ulang tersebut menyebabkan perbedaan sifat-sifat material beton yang dihasilkan. Persentase penurunan kuat lentur beton agregat daur ulang dengan komposisi 25 % agregat kasar daur ulang dan 0 % agregat halus daur ulang adalah 1.26 %, sedangkan beton agregat daur ulang dengan komposisi 0 % agregat kasar daur ulang dan 25 % agregat halus daur ulang adalah 6.33 %. Ini menunjukkan bahwa penggunaan agregat kasar daur ulang dengan persentase 25 % lebih baik dari pada penggunaan agregat halus daur ulang dengan persentase 25 % untuk pengujian kuat lentur beton. Pada pengujian susut, nilai persentase pertambahan susut beton agregat daur ulang dengan komposisi 0 % agregat kasar daur ulang dan 25 % agregat halus daur ulang adalah 10.53 %, sedangkan dengan komposisi 25 % agregat kasar daur ulang dan 0 % agregat halus daur ulang adalah 5.26%. Ini menunjukkan bahwa penggunaan agregat kasar daur ulang dengan persentase 25 % lebih baik dari pada penggunaan agregat halus daur ulang dengan persentase 25 % untuk pengujian susut.

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Now ready mix is very well known to make construction of building, but the usage often more supply that throw in anywhere, so it will decrease the fertilizer of soil and destroy the ecosystem. To against that, the solution is to recycled aggregate. We need research chemical properties of the materials and then to be analyzed to understand the difference between natural and recycled aggregates. The method and procedure for testing of the recycled aggregate materials are in accordance with the ASTM standard. Concretes are made from normal aggregate and mix both normal and recycled aggregate. Concrete strength is 25 MPa. After that, test of flexural strength in 28th day old and shrinkage during 56 days. Based on the experimental works, recycled aggregates contain mortar. The existence of mortar content in recycled aggregates affects to the accretion of absorption of aggregate, more porous, less hardness. Some of the difference of qualities, physical and chemical properties of recycled aggregates cause the difference of properties of the resulted concrete materials. The difference properties consist of the reduction of flexural strength and increase of shrinkage. The reduction of percentage recycled aggregate concrete of composition 25 % coarse recycled aggregate and 0 % fine recycled aggregate was 1.26 %, while recycled aggregate concrete of composition 0 % coarse recycled aggregate and 25 % fine recycled aggregate was 6.33 %. This indicate that usage recycled coarse aggregate was prefer than recycled fine aggregate for flexural strength. For shrinkage, percentage accretion value of composition 0 % coarse recycled aggregate and 25 % fine recycled aggregate was 10.53 %, while 25 % coarse recycled aggregate with 0 % fine recycled aggregate was 5.26%. This indicate that usage of coarse aggregate of recycle with percentage 25 % was better the than usage of fine aggregate of recycle with percentage 25 % for the examination of length change.

Abstrak :
Meningkatnya penggunaan kendaraan beroda di Indonesia secara tidak langsung akan mendorong kebutuhan infrastruktur jalan raya yang berkualitas baik demi menyediakan rasa nyaman bagi para pengendara. Hal ini tentu juga berefek pada kebutuhan material yang digunakan dalam konstruksi perkerasan jalan, maka dari itu pemanfaatan material limbah menjadi salah satu upaya dalam mengurangi penggunaan material alami, serta diharapkan dapat meningkatkan mutu dari infrastruktur itu sendiri. Pada penelitian ini akan dilakukan pengujian penggunaan agregat limbah beton (RCA) dan penambahan limbah plastik LDPE pada campuran aspal terhadap nilai volumetrik Marshall. Akan digunakan limbah beton sebagai substitusi partial agregat alami dan penambahan limbah plastik LDPE dengan variasi kadar 3%, 4%, 5%, 6%, dan 7%. Pengujian dilakukan menggunakan Marshall Standard dan Marshall Immerson untuk didapatkan nilai volumetrik Marshall serta kadar optimum penggunaan limbah plastik pada campuran. ......The increasing use of wheeled vehicles in Indonesia will indirectly drive the need for good quality road infrastructure in order to provide comfort for motorists. This of course also has an effect on the need for materials used in road pavement construction, therefore the use of waste materials is one of the efforts to reduce the use of natural materials, and is expected to improve the quality of the infrastructure itself. In this study, testing the use of Recycled Concrete Aggregate and the addition of LDPE plastic waste to asphalt mixtures for the Marshall volumetric value will be carried out. Recycled Concrete Aggregate will be used as a partial substitute for natural aggregate and the addition of LDPE plastic waste with varying rate of 3%, 4%, 5%, 6% and 7%. Tests were carried out using Marshall Standard and Marshall Immerson to obtain Marshall volumetric values in the mixture.

Abstrak :
The civil engineering sector accounts for a significant percentage of global material and energy consumption and is a major contributor of waste material. The ability to recycle and reuse concrete and demolition waste is critical to reducing environmental impacts in meeting national, regional and global environmental targets. Handbook of recycled concrete and demolition waste summarises key recent research in achieving these goals. Part one considers techniques for managing construction and demolition waste, including waste management plans, ways of estimating levels of waste, the types and optimal location of waste recycling plants and the economics of managing construction and demolition waste. Part two reviews key steps in handling construction and demolition waste. It begins with a comparison between conventional demolition and construction techniques before going on to discuss the preparation, refinement and quality control of concrete aggregates produced from waste. It concludes by assessing the mechanical properties, strength and durability of concrete made using recycled aggregates. Part three includes examples of the use of recycled aggregates in applications such as roads, pavements, high-performance concrete and alkali-activated or geopolymer cements. Finally, the book discusses environmental and safety issues such as the removal of gypsum, asbestos and alkali-silica reaction (ASR) concrete, as well as life-cycle analysis of concrete with recycled aggregates.

Abstrak :
Balok merupakan elemen struktur yang utamanya menahan lentur dan geser dengan atau tanpa gaya aksial atau torsi. Tujuan penelitian ini adalah mengamati perubahan natural frekuensi terhadap pembebanan bertahap pada balok beton bertulang dengan agregat daur ulang. Studi dilakukan secara eksperimen, yakni menggunakan beton dengan agregat kasar daur ulang (kuat tekan fc’ 20,74 MPa). Balok yang digunakan berukuran 3000 × 150 × 250 mm3 yang diberi beban semi-siklik dengan metode pembebanan four-point loading. Pembebanan dilakukan dalam 4 siklus, yaitu siklus 2 ton, 4 ton, 6 ton, dan 8 ton. Respon struktur berupa grafik perpindahan vs beban dan waktu, regangan vs beban diolah dari hasil pengujian menggunakan Digital Image Correlation (DIC) dan pengukuran manual dengan LVDT, dial gauge, dan strain gauge. Karakteristik dinamik balok berupa frekuensi alami dan rasio redaman diperoleh dengan alat accelerometer. Hasil eksperimen tersebut dibandingkan dengan hasil perhitungan teoritis. Analisis menunjukan bahwa balok mencapai batas elastis pada beban 8000 kg. Frekuensi alami cenderung menurun terhadap penambahan beban, hal dikarenakan nilai kekakuan balok yang telah diberi beban akan turun akibat muncul retakan. Nilai rasio redaman pada balok RAC cenderung menurun terhadap penambahan pembebanan bertahap. ......Beams are structural elements that primarily resist bending and shear with or without axial or torsional forces. The purpose of this study was to observe the natural frequency changes to the gradual loading of reinforced concrete beams with recycled aggregate. The study was conducted experimentally, using concrete with recycled coarse aggregate (compressive strength fc' 20.74 MPa). The beam used is 3000 × 150 × 250 mm3 which is given a semi-cyclic load with a four-point loading method. The loading is carried out in 4 cycles, namely 2 tons, 4 tons, 6 tons, and 8 tons. Structural responses in the form of graphs of displacement vs. load and time, strain vs. load were processed from the test results using Digital Image Correlation (DIC) and manual measurements with LVDT, dial gauge, and strain gauge. The dynamic characteristics of the beam in the form of natural frequencies and damping ratio were obtained by using an accelerometer. The experimental results are compared with the results of theoretical calculations. The analysis shows that the beam reaches its elastic limit at a load of 8000 kg. The natural frequency tends to decrease with increasing load, this is because the stiffness value of the beam that has been given a load will decrease due to cracks appearing. The value of the damping ratio in the RAC beam tends to decrease with the addition of gradual loading.

Abstrak :
ABSTRAK
Pemanfaatan kembali limbah beton untuk dijadikan bahan konstruksi telah banyak dilakukan di negara-negara lain. Sayangnya, pemanfaatan limbah beton di Indonesia barulah sebatas untuk timbunan. Penggunaan limbah beton sebagai agregat halus akan mengurangi kuat tekan dan meningkatkan daya serap air. Oleh karena itu, penelitian ini bertujuan untuk memelajari sifat mekanis mortar dengan agregat halus daur ulang dan bahan tambah abu terbang. Variasi abu terbang yang akan menggantikan semen adalah 0 , 5 , 10 , 15 , 20 , 25 . Pengujian yang dilakukan adalah uji kuat tekan, lentur, modulus elastisitas, susut, dan daya serap air. Dari hasil pengujian didapatkan bahwa kuat tekan dan lentur terbesar didapat oleh mortar dengan variasi 10 dengan kuat tekan 33,39 MPa yang memenuhi target mortar tipe M 17,2 MPa . Modulus elastisitas terbesar ditunjukan oleh mortar dengan variasi 15 . Nilai susut terbesar dihasilkan oleh mortar dengan variasi 20. Dan nilai daya serap air terkecil dihasilkan oleh mortar dengan variasi 25.

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ABSTRACT
The re use of concrete waste to be used as construction material has been done in many other countries. Unfortunately, the utilization of concrete waste in Indonesia is only limited to embankment. The use of waste concrete as a fine aggregate will reduce the compressive strength and increase water absorption. Therefore, this study aims to study the mechanical properties of mortar with recycled fine aggregate and fly ash materials. The variations of fly ash that will replace the cement are 0 , 5 , 10 , 15 , 20 , 25 . Tests conducted are test of compressive strength, flexural, elastic modulus, shrinkage, and water absorption. From the test results it was found that the largest compressive strength and flexure was obtained by mortar with a 10 variation with a compressive strength of 33.39 MPa that meets the target of M type mortar 17.2 MPa . The greatest elasticity modulus is shown by mortar with a variation of 15 . The greatest shrinkage value was produced by mortar with a variation of 20 . And the smallest water absorption value is produced by mortar with 25 variation.