The Report presents a comprehensive summary of the extensive studies conducted on fly ash-based geopolymer concrete. Test data are used to identify the effects of salient factors that influence the properties of the geopolymer concrete in the fresh and hardened states. These results are utilized to propose a simple method for the design of geopolymer concrete mixtures. Test data of various shortterm and long-term properties of the geopolymer concrete are then presented. The last part of the Report describes the results of the tests conducted on large-scale reinforced geopolymer concrete members and illustrates the application of the geopolymer concrete in the construction industry. The economic merits of the geopolymer concrete are also mentioned.

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To reduce greenhouse gas emissions, efforts are needed to develop environmentally friendly construction materials. This paper presents the development of fly ash-based geopolymer concrete. In geopolymer concrete, a by-product material rich in silicon and aluminum, such as low-calcium (ASTM C 618 Class F) fly ash, is chemically activated by a high-alkaline solution to form a paste that binds the loose coarse and fine aggregates, and other unreacted materials in the mixture. The test results presented in this paper show the effects of various parameters on the properties of geopolymer concrete. The application of geopolymer concrete and future research needs are also identified.

Fly ash-based geopolymer concrete is manufactured without using portland cement at all. This type of concrete has environmental benefit as it has very low greenhouse gas emission compared to that resulted from the production of portland cement. In addition, it also utilizes waste or by-product material that makes it more environmentally friendly. This paper presents the study of drying shrinkage of heat-cured fly ash-based geopolymer concrete. Geopolymer concrete in this study used low-calcium fly ash as its source material, alkaline solution and aggregates normally used for ordinary portland cement concrete. Four series of test specimens with different compressive strength were prepared to study the drying shrinkage of this concrete. The test results were then compared with the calculated results of drying shrinkage as predicted by Gilbert Method which is normally used for ordinary portland cement concrete. Test results show that the heat-cured fly ash-based geopolymer concrete undergoes very low drying shrinkage. The drying shrinkage strain at one year as calculated using Gilbert Method is much higher, about five to seven times, compared to the measured drying shrinkage strain from the tests.

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Fly ash-based geopolymer concrete is manufactured using fly ash as its source material and does not use Portland cement at all. Beside fly ash, alkaline solution is also utilized to make geopolymer paste which binds the aggregates to form geopolymer concrete. This paper presents the study of creep behaviour of fly ash-based geopolymer concrete. Four series of specimens with various compressive strengths were prepared to study its creep behaviour for the duration of test up to one year. The test method followed the procedures applied for Ordinary Portland Cement (OPC) concrete. Test results show that fly ash-based geopolymer concrete undergoes low creep which is generally less than that of OPC concrete. After one year of loading, the results for specific creep of fly ash-based geopolymer concrete in this study ranges from 15 to 29 microstrain for concrete compressive strength 67-40 MPa respectively. From the test results, it is also found out that the creep coefficient of fly ash-based geopolymer concrete is about half of that predicted using Gilbert's Method for OPC concrete.

Kabupaten Minahasa Tenggara mengalami peningkatan penduduk setiap tahunnya. Peningkatan ini mengakibatkan volume dan jenis sampah juga mengalami peningkatan. Tempat Pemrosesan Akhir (TPA) Sampah merupakan tahap akhir dari pemrosesan sampah dimana sampah hasil pengumpulan atau pengangkutan maupun sisa hasil dari pemrosesan daur ulang disuatu daerah atau kota ditampung untuk dikelola. Untuk itu TPA harus dipersiapkan dengan baik dan sesuai dengan standar yang berlaku agar tidak mencemari lingkungan sekitar dan berdampak buruk bagi masyarakat. Tujuan dari penelitian ini adalah 1) mengetahui tahapan pemilihan lokasi TPA sesuai standar yang berlaku menggunakan Sistem Informasi Geografis (SIG); 2) mengetahui dimana alternatif lokasi tempat pemrosesan akhir (TPA) sampah di Kab. Minahasa Tenggara. Metode yang digunakan adalah deskriptif kuantitatif. Berdasarkan hasil penelitian bahwa, tahapan pemilihan lokasi TPA berdasarkan SNI 03-3241-1994 dan Peraturan Menteri PU Republik Indonesia Nomor 03/PRT/M/2013 terdapat 3 tahapan yaitu Tahap Regional , Tahap Penyisih dan Tahap Penetapan . Tiga tahap tersebut dianalisis menggunakan SIG dengan metode Buffering dan Overlay dengan pendekatan kuantitatif Binary. Lokasi yang menjadi alternatif TPA dengan perolehan skor tertinggi 311 yaitu berada di Kecamatan Pusomaen. Lokasi tersebut berada cukup jauh dengan lokasi TPA eksisting sehingga alternatif TPA terpilih ini dapat menjadi masukan bagi pemerintah untuk perencanaan tata ruang di wilayah Kabupaten Minahasa Tenggara.

This study presents the effect of utilizing cellulose microfibers obtained through extraction from bamboo as reinforcement on mortar mixtures. The mixture proportions used in this experiment are 0.5%, 1%, 1.5%, and 2% of bamboo cellulose fiber by weight of cement as additional material in mortar mixture. It was found that the optimum compressive strength of 36.4 MPa was achieved by the sample with 1.5% of bamboo cellulose fiber as additional material with water to binder ratio of 0.5. A similar trend was also found in the result of flexural strength of mortar due to bamboo cellulose fiber addition, reaching the value of 6.31 MPa on the 28th day, which is 52% higher than the flexural strength of control mortar. From the porosity results, the percentage of mortar porosity containing micro-fibers ranged from 4.6-9.1%, lower than the porosity of control mortar, indicating that the addition of fibers led to fill in the pores, resulting in a denser cement matrix. The performances of the cellulose fiber contributed to the strength development and porosity resistance of mortar even with low volume fraction, making it a potential to be used as material building construction, for instance, masonry mortar, repair mortar, rendering mortar, joint filler, waterproof mortar, decorative mortar and for precast elements in construction. The research findings also provide new perspective on the utilization of natural cellulose fibers as a sustainable construction material.