Development of Geopolymer Concrete with Different Curing Conditions

Abstract

Environmental issues resulted from cement production have become a major concern today. To develop a sustainable future it is encouraged to limit the use of this construction material that can affect the environment. Cement replacement material was proposed to partially replace cement portion in concrete. Geopolymer is a part of inorganic polymer material that has similar bonding function like cement in concrete. It consists of alkaline solutions and geological source material. Alkaline liquids used in this research are 8 M sodium hydroxide (NaOH) solution and sodium silicate (Na 2 SiO 3 ) solutions, while source materials are fly ash and microwave incinerated rice husk ash (MIRHA). Three different curing regimes, namely hot gunny curing, ambient curing, and external exposure curing, were applied to obtain suitable method that was suitable with cast in situ application. Geopolymer concrete samples were tested on their compressive strength and microstructure properties. It was found that external exposure curing had the highest compressive strength compared to other two curing methods. Scanning electron microscopy analysis also showed better improvement in interfacial transition zone for concrete sample with external exposure curing.Keywordsgeopolymer, sodium hydroxide, sodium silicate, fly ash, MIRHA AbstrakDampak terhadap lingkungan akibat produksi semen telah menjadi masalah yang besar pada saat ini. Untuk mengembangkan masa yang akan datang yang lebih berkelanjutan maka diperlukan usaha untuk membatasi penggunaan material konstruksi ini yang dapat mempengaruhi lingkungan. Material pengganti semen telah diusulkan untuk mengganti sebagian porsi semen dalam beton. Geopolimer adalah bagian dari polimer bukan organik yang mempunyai sifat mengikat seperti semen pada beton. Material tersebut terdiri dari cairan alkalin dan material dari sumber geologi. Cairan alkalin yang dipakai dalam penelitian ini adalah cairan 8 M Natrium Hidrosikda (NaOH) dan cairan Natrium silikat (Na 2 SiO 3 ), sementara material sumber geologi adalah Abu Terbang dan Abu Sekam Padi yang dibakar memakai gelombang-mikro (microwave incinerated rice husk ash/MIRHA). Tiga macam cara perawatan, yaitu perawatan memakai karung panas, perawatan suhu ruang dan perawatan di tempat terbuka tanpa perlindungan dari cahaya matahari, telah digunakan untuk mendapatkan metoda yang tepat untuk aplikasi cor setempat. Contoh beton geopolimer telah diuji kuat tekannya dan sifat-sifat struktur mikronya. Dari hasil uji tersebut ditemukan bahwa perawatan di tempat terbuka tanpa perlindungan dari cahaya matahari mempunyai kuat tekan tertinggi dibandingkan dengan dua cara perawatan lainnya. Analisa dengan cara pemindaian memakai mikrosokop elektron juga menunjukkan perbaikan zone transisi antar muka (interfacial transition zone) untuk beton dengan perawatan di tempat terbuka tanpa perlindungan dari cahaya matahari.

Methods of curing geopolymer concrete: A review

“…He found that the rate of strength development for ambient cured geopolymer concrete resembles that of OPC Concrete and therefore be used for onsite constructions. Similarly, Nuruddin et al (2011) found that the weight of fly ash geopolymer concrete correspond to that of OPC concrete. Analysis of microstructural properties of the specimens was shown in Fig.…”

“…However, this method of curing is difficult to achieve for cast in situ applications. In another research Nuruddin et al (2011) prepared three separate regimes of curing, namely hot burlap curing, ambient curing, and oven curing. Geopolymer concrete specimens were produced by activating fly ash and microwave incinerated rice husk ash (MIRHA) with 8 molar solutions of sodium hydroxide solution and sodium silicate.…”

Experimental Analysis of Non-Destructive Testing (NDT) on Ground Granulated Blast-Furnace Slag (GGBS) based Geopolymer Concrete

“…The mixing process involves two stages, dry mix and wet mix [12]. Coarse aggregate, fine aggregate, and GGBS will be mixed initially in rotating pan mixer for 3 to 5 minutes.…”

Experimental Study on Suitability of Geopolymer Concrete Paver on Medium Traffic Condition Highway

“…According to Nuruddin et al [5] mixing process can be divided into two stages, dry mix and wet mix. Initially coarse aggregate, fine aggregate and GGBS will be mixed together in rotating pan mixer for 3 to 5 minutes.…”