Compressive strength, drying shrinkage and chemical resistance of concrete incorporating coal bottom ash as partial or total replacement of sand

2014 ◽  
Vol 68 ◽  
pp. 39-48 ◽  
Author(s):  
Malkit Singh ◽  
Rafat Siddique
Author(s):  
Gum Sung Ryu ◽  
Kyung Taek Koh ◽  
Gi Hong An ◽  
Jang Hwa Lee

This paper evaluates the strength, shrinkage and durability characteristics of concrete using 100% fly ash and bottom ash as binder. It is seen that the compressive strength of activated fly ash and bottom ash concrete reaches respectively 25 MPa and 30 MPa, and that the change in strength is insignificant as per the content of bottom ash powder. Moreover, the total amount of shrinkage of the activated bottom ash concrete appears to be larger than that of the activated fly ash concrete. In addition, the drying shrinkage and durable performance of the activated ash geopolymer concrete is verified to be superior to that of ordinary cement concrete.


2019 ◽  
Vol 961 ◽  
pp. 51-56 ◽  
Author(s):  
Agus Dwi Anggono ◽  
Zaennal Muttaqiem ◽  
Agung Setyo Darmawan ◽  
Tri Widodo Besar Riyadi ◽  
Agus Yulianto ◽  
...  

Garbage is a serious problem if it is not managed properly, both organic and non-organic. Inorganic waste, for example, plastic, metal, glass, and charcoal from coal combustion are difficult to decompose in the soil. HDPE (high-density polyethylene) plastic is one type of inorganic waste that is difficult to decompose, but this plastic can be recycled. The objective of the study is to develop light cement blocks by using the waste of HDPE, coal bottom ash and cement. The research guide was referred to SNI (Indonesian National Standard). The SNI-03-6825-2002 is for testing of the compressive strength and SNI 03-0349-1989 for the testing of the water absorption. The size of the specimen was 5 x 5 x 5 cm. In this study, the compositions of HDPE: coal bottom ash were varied by 70%: 0%, 60%: 10%, 50%: 20%, and 40%: 30%. The Holcim cement was 30% of the volume fraction. Testing was conducted after the specimens stay in 7 and 28 days. For the 7 days old of specimens, the highest compressive strength has resulted from 50%:20% composition with the value of 5.88 N/mm2. For the 28 days old specimens, the highest compressive strength was 8.34 N/mm2. The lowest water absorption test was delivered by the more coal bottom ash in the composition of 40%:30%. It was 16.971%. The more coal bottom ash, the less water absorption. The mean of specimens density was 1.076 gr/cm3. The result of the research shows that recycles HDPE and coal bottom ash as concrete block meet the required strength.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Sungil Hong ◽  
Hyo Kim

Abstract Microwave energy has been shown to be effective for geopolymer synthesis due to its fast and penetrative heating characteristics; however, the changes in the physicochemical properties of the geopolymer, resulting from the microwave irradiation, have not been fully elucidated. Therefore, this study is aimed at investigating the effect of the microwaving on the properties of coal bottom ash(CBA) geopolymers. We prepared geopolymer samples by casting a mixture of ground CBA and 14 M NaOH solution against cubic molds with a hand press machine, followed by pre-curing in a dry oven at 75 °C for 24 h and microwaving under various powers and durations. The compressive strength strongly depended on the moisture content, i.e., the strength increased from 21 to 65 MPa or higher as the moisture content decreased to critical values, after which the strength began to decrease. The results showed that microwave energy stimulated an additional geopolymerization by evaporating the redundant free water. This led to the strength gain, although the over-irradiation generated a high internal stress and poor structural integrity, which resulted in the strength loss. Therefore, the appropriate application of microwave energy is a promising option for synthesizing high-strength geopolymers in a cost- and time-effective manner.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
In-Hwan Yang ◽  
Jihun Park ◽  
Nhien Dinh Le ◽  
Sanghwa Jung

Most previous studies on the strength properties of coal bottom ash (CBA) concrete have focused on concrete with a normal compressive strength, and thus, studies on the strength properties of high-strength concrete (HSC) containing CBA are limited. Therefore, the effects of replacing fine aggregates with CBA and variations in the curing age on the strength properties of HSC with a compressive strength of greater than 60 MPa were investigated in this study. The different CBA contents included 25, 50, 75, and 100%, and the different curing ages were 28 and 56 days. The mechanical properties of the HSC with CBA incorporated as fine aggregates were examined. The experimental results revealed that CBA could be partially or totally substituted for fine aggregates during HSC production. The test results also showed that the compressive, splitting tensile, and flexural strengths of the HSC containing CBA fine aggregates slightly decreased as the CBA content increased. Moreover, useful relationships between the compressive strength, splitting tensile strength, and flexural strength were suggested, and the predictions reasonably agreed with the measurements. Compared to those of the control specimen, the pulse velocities of the HSC specimens at various CBA contents decreased by less than 3%. In addition, equations for predicting the strength values of CBA concrete by using the ultrasonic pulse velocity were suggested.


2020 ◽  
Vol 6 (1) ◽  
pp. 13 ◽  
Author(s):  
Noraziela Syahira Baco ◽  
Shahiron Shahidan ◽  
Sharifah Salwa Mohd Zuki ◽  
Noorwirdawati Ali ◽  
Mohamad Azim Mohammad Azmi

Coal Bottom Ash (CBA) is a mineral by-product of thermal power plants obtained from the combustion of coal. In many countries, CBA wastes are identified as hazardous materials. The utilization of CBA can help in alleviating environmental problems; thus, this research was carried out to explore the possibility of its use as cement replacement in concrete manufacturing. Presently, In Malaysia, research that concerns about the use of CBA as cement replacement is very limited. Therefore, this study was aimed to investigate the properties of CBA as cement replacement and to identify the optimum percentage of untreated CBA as cement replacement. The CBA used in this study were taken from the Tanjung Bin power plant. In this research, the amount of CBA in the concrete mixture varied from 20% to 40% to replace cement. The properties of concrete containing CBA as cement replacement was examined through slump test, sieve analysis, concrete compressive strength test and splitting tensile strength test. The compressive strength test and splitting tensile strength test were performed at 7 and 28 days of curing time. Based on this research, it can be concluded that the optimum percentage of CBA as cement replacement is 25% for a curing time of both 7 and 28 days with the concrete compression strength of 45.2 MPa and 54.6 MPa, respectively. Besides, the optimum percentage for tensile strength is also at 25% CBA for a curing period of both 7 and 28 days with the tensile strength of 2.91 MPa and 3.28 MPa, respectively. 


2021 ◽  
Author(s):  
Sajjad Ali Mangi ◽  
Mohd Haziman Wan Ibrahim ◽  
Norwati Jamaluddin ◽  
Mohd Fadzil Arshad ◽  
Shabir Hussain Khahro ◽  
...  

Abstract This study investigated the influence of Coal Bottom Ash (CBA) on the concrete properties and evaluate the effects of combined exposure of sulphate and chloride conditions on the concrete containing CBA. During concrete mixing, cement was replaced with CBA by 10% of cement weight. Initially, concrete samples were kept in normal water for 28 days. Next, the specimens were moved to combined solution of 5% Sodium sulphate (Na2SO4) and 5% sodium chloride (NaCl) solution for further 28 to 180 days. The experimental findings demonstrated that the concrete containing 10% CBA (M2) gives 12% higher compressive strength than the water cured normal concrete (M1). However, when it was exposed to solution of 5% Na2SO4 and 5% NaCl, gives 0.2% greater compressive strength with reference to M1. The presence of 10% CBA decreases the chloride penetration and drying shrinkage around 33.6% and 29.2% respectively at 180 days. Hence, this study declared 10% CBA as optimum that can be used for future research.


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