EFFECT OF FLY ASH AND RICE HUSK ASH ON PERFORMANCE OF MORTAR

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1 Journa of Research in Engineering and Appied Sciences EFFECT OF FLY ASH AND RICE HUSK ASH ON PERFORMANCE OF MORTAR B.P. Nandurkar1, Dr. A.M. Pande2 1,2 1 Assistant Professor, 2Director, R&D, YCCE & Professor Civi Engineering Department,Yeshwantrao Chavan Coege of Engineering Coege, Wanadongari, Nagpur, India. Abstract In, India, construction industry speciay housing sector predominanty uses cement sand mortars for masonry construction. Cements being used in these mortars are predominanty high eary strength cements ike 53 grades or PPC. The practice in the other deveoped countries significanty differs from that of India as high eary strength cements are not recommended in these countries, as they may ead to deveopment of minor cracks in mortars, resuting in compromise on performance of masonry. Simiar text is mentioned in.2 section of IS: Thus, there is great need to deveop masonry mortars incorporating fy ash and rice husk ash to make masonry structure more performing and achieving the compressive strength as prescribed in Indian standards. The performance of cement sand mortar made with composite cementing components ike ordinary portand cement, agricutura waste rice husk ash and industria waste fy ash were studied in this work. Cement was repaced upto 4% of its weight by fy ash and rice husk ash. The proportion of mortar was taken 1:3 (Cementing component: Sand). Compressive strength test was conducted at 3, 7 and 28 and 9 days of curing. The resuts indicate repacement of 2 to 25% of cement with fy ash significanty improves the strengths and performance of mortar. The strength of rice husk ash mortar mixes reduces as the percentage of rice hush ash in the mixes is increased. Water absorption test resuts were on higher side, when cement was repaced by rice husk ash. The outcome of this research is expected in paving way in deveopment of new and high performing masonry mortar combinations. Key Words : Fy ash; rice husk ash; mortar; compressive strength; drying shrinkage 1. Introduction A. M. Pande[1] suggested mortars with FA repacement of cement up to 5% can be used in masonry work. M. Akram Tahir et.a., [2] stated that the resistance to acid attack of mortars containing FA up to 3% was better. Mohammed [3] showed that after 28 days of curing with the same w/b ratio, the compressive strength and the tensie strength of the cement mortars with Metakaoin were having higher vaues than the controed mix mortar. According to O. Cizer [4] hardening of cacium hydroxide and cacium siicate binders with RHA and ime in different compositions. And from his research RHA mortar mixes indicated a ong-term strength progress. M.J. Mosquera et a., [5] had estabished correation between pore radius parameter and the vapor diffusion coefficient of mortar mixes. According to Cengiz Duran Atis [6] resuts show that FA reduced drying shrinkage of the mortar by 4%. M.P. Seabra [7] mentioned that the mortars workabiity is affected by severa parameters, namey, the binder/aggregate and water/binder ratios. Eva Vejmekova [9] showed that the ime pozzoan mortars have significanty better mechanica properties and frost resistance than the reference ime mortar. S. A. Khadikar [1] specified that the partice characteristics determine the performance of the resutant Concrete. The mixture of cementing component and fine aggregates together form a mortar mix. There are various types of mortar mixes given in IS: 225. In this work, mortar mix of proportion 1:3 was taken as reference. The ordinary Portand cement (OPC) of 43 grade was used as a main cementitious component. Fy ash (FA) and rice husk ash (RHA) were aso used as pozzoanic or admixture components in combination with cement. It is we known fact that, during manufacturing of 1 tone of Portand cement, cements industry required equa amount of earth resources and equa amount of CO2 are reeased into the nature. Past researches have been focusing towards the utiization of waste materias in concretes. Pozzoans from industria and agricutura byproducts such as FA and RHA are receiving more attention because; their uses improve the properties of the cement concrete. The uses of such by-products not ony resuts in reduction of the cost of construction but aso reduces the negative environmenta effects. To save the nature, human heath and to reduce the cost of masonry construction, repacing cement with these by-products (FA or RHA) is essentia. In this work, an attempt is made to highight enhancement in the properties of cement sand mortars (CSM) by repacing the cement with FA and RHA. ISSN (Print) : , ISSN (Onine) : JREAS, Vo. 3, Issue 1, January 218

2 2. Experimenta Detais sieve and used as a fine aggregate. The river sand was tested for fineness moduus and specific gravity and was found 2.32 and The mixture of cement and fine aggregate in the form of sand together forms a mortar mixes. There are various types of mortar mixes given in IS: 225 and IS: 195. In this work, mortar mix of proportion 1:3 has been taken. The 43 grade of ordinary Portand cement was use as a main cementitious component. FA and RHA were used as secondary cementitious components in combination with cement Mixture proportions and sampe preparation The mix proportion of 1:3 was used in this work. Three types of cementitious component were used in this work and are cement, cement with FA and cement with RHA. Cement was repaced by FA and RHA with varying percentage from 2% to 4% in increment of 5%. The cementing component combinations are cement, cement with FA and cement with RHA were taken and shown in tabe 1. For a proportion of 1:3 mixes, tota 11mixes were prepared incuding controed mix (cement: sand proportion). For each mix, the water cement ratio was determined from workabiity criteria point of view and is shown in tabe 1. As per IS specification, the water cement ratio for controed mix was taken as.5. The water cement ratio for cement with FA mortar mixes found to be.55. The water cement ratio was increased when cement was repaced by RHA, due to workabiity requirements. Materias used The cement was ordinary Portand cement (OPC) of grade 43. The by-product in the form of FA and RHA were use in this work as a cementitious materia. FA were coected from Koradi power pant ocated in Nagpur, Maharashtra state, India.RHA were coected from Eora Paper Mis, ocated in Tumsar, Dist. Bhandara, Maharashtra state, India. These ingredients (FA and RHA) were used as a partia repacement of cement. Before using FA and RHA, it was sieved through 9-micron sieve. For making mortar mix of proportion 1:3, OPC 43 grade and Natura River sand was used. River sand was sieved through 4.75 mm Tabe1 Combinations of cement, FA and RHA mortar mixes of proportion 1:3 and their water binder ratio SN 3. Type of Mortar Binder 1 S 3 2 Cementing component (%) w/c Ratio C FA RHA C 1.5 S S S S S S S S S S Experimenta Testing and kept in stee mods for 24 hours and then were demoded and moved into a curing tank unti testing. The specimens were tested in tripicate sets. For preparation of mortar mix of proportion 1:3, OPC 43 grade and natura river sand were used. There are three types of cementitious component used, they are cement, cement with FA and cement with RHA. Cement was repaced by FA and RHA with varying percentage from 2% to 4% in increment of 5%. The specimens were cast ISSN (Print) : , ISSN (Onine) : Compressive Strength Test Compressive strength test resuts cacuated according to IS: For compressive strength test, cube specimens of dimensions 5x5x5 mm were casted. The 23 JREAS, Vo. 3, Issue 1, January 218

3 mods were fied with mortar of 1:3proportions with varying percentage of cement, cement with FA and cement with RHA. After 24 hours, the specimens were demoded and transferred to curing tank wherein they were curing for 3, 7, 28 & 9 days. These cubes have tested on compression testing machine. The faiure oad was noted in the compression testing machine. For each mix three cubes were casted and after testing average vaues were reported Water Absorption A mortar mixes are subjected to water absorption. The amount of water absorbed depends on water tightness of the mixes. A mortar mix of water absorption beow 1 % are said to be good mortar mixes. The cubes for water absorption test were casted as per ASTM C642 [2] and the test was carried out after 28 days and 9 days of curing. For the water absorption test, the cubes were first kept in an oven 15 5 oc for 24 hours weighted (dry weight, Wd). Then they were immersed in water for further 24 hours and weighted again (wet weight, Ww). The water absorption was then cacuated by using the foowing formua water absorption (%) = 3.3. Fig. 1: Compressive strength of cement mortar mixes with FA Ww - Wd x 1 Wd Drying Shrinkage Drying shrinkage test was done as per IS 431(part-1)1988 & by ASTM C596 [19]: Drying shrinkage was cacuated as ength change and designated by % of ength change. The specimens were tested on 7, 35, 56 and 9days after casting under specified condition. After 7 days, the initia ength of shrinkage specimen was measured before pacing them in the humidity chamber. The ength of the shrinkage specimen was measured at the age of35, 56 and 9 days, respectivey. The ength change, Lx was cacuated by the foowing formua: x = Fig. 2 : Gain in compressive strength of cement mortar mixes 1:3 with FA CRD - initia CRD x 1 G Lx = ength change of specimen at any age, %, CRD = difference between the comparator reading of thespecimen and the reference bar at any age, and G 4. = the gage ength (1 in. [25 mm] Resuts The resuts of various tastings are presented in graphica form from Figure number 1 to 1. Fig. 3 : Compressive strength of cement mortar mixes with FA ISSN (Print) : , ISSN (Onine) : JREAS, Vo. 3, Issue 1, January 218

4 Fig. 7 : Water absorption vs % of RHA at various ages of cement mortar mixes. Fig. 4 : Gain in compressive strength of cement mortar mixes 1:3 RHA Fig. 5 : Water absorption vs % of FA at various ages of cement mortar mixes. Fig. 8 : Water absorption of cement mortar mixes with RHA at 28 days and 9 days age. Fig. 9 : % change in ength of cement mortar mixes at different ages with FA. Fig. 6 : Water absorption of cement mortar mixes with FA at 28 days and 9 days age. ISSN (Print) : , ISSN (Onine) : JREAS, Vo. 3, Issue 1, January 218

5 increases, it eads to increase in water absorption. S36 the RHA mortar shows ony water absorption beow 1% at 9 days of age. 5.4 Drying shrinkage / change in ength The drying shrinkage or ength change of FA mortar mixes and RHA mortar mixes are shown in Figure-9 and Figure-1. FA mortar mixes S31 and S32 show better performance in change in ength as compared to a other mortar mixes. The RHA mortar S36 shows good resut as compared to other RHA mortar mixes. It was observed that mortar mixes containing 25% FA as a repacement of cement gave higher compressive strength at eary age i.e., at 3 and 7 days of age than the controed mix mortar. When cement was repaced by RHA up to 25% repacement eve, the 28 and 9 days compressive strength was found amost simiar to the controed mix mortar. Up to 2% repacement of cement by FA, it was observed that the water absorption was marginay reduced. At more than 3% repacement eve it was more than the controed mix. This indicates that up to 25% repacement eve the contribution of FA in pore refinement due to secondary C-H-S formation was ceary visibe. However, in case of RHA, the water absorption resuts were on higher side. A the FA mortar mixes having ess than 1% of water absorption, this indicates that FA mortar mixes are better performing mortar mixes The mortar containing 2 to 25% FA and 2 to 3 RHA, significanty contributes towards better 6. Concusion Fig. 1 : % change in ength of cement mortar mixes at different ages with RHA. 5. Discussion 5.1 Compressive strength of FA mortar mixes The compressive strength deveopment of cement mortar, cement with FA mortar at the ages of 3, 7, 28 and 9 curing days is shown in Figure-1. Higher compressive strength was observed in controed mix mortar (S3) than mortar mixes with FA at the age of 28 days and 9 days. S32 mortar shows better resut at the eary ages 3 and 7 days as compare with other mixes. The compressive strength of S3 and S32 mortar are very simiar at 28 and 9-day age. Figure-2 show that, the rate of gain in strength per day of S32 mortar is higher as compared to other FA mortar mixes. 5.2 Compressive strength of RHA mortar mixes The compressive strength of controed mix mortar and mortar containing RHA are shown in Figure-3. Mortar S36 and S37 gave amost same strength at 28 and 9 days age. The water binder ratio was varied between.7 to.9 in order to achieve the workabiity of RHA mortar mixes. Due to higher water binder ratio (w/(c+rha)), at a the ages the compressive strength of RHA mortar mixes was on ower side as compared to controed mix mortar as shown in Figure-3. From the resut, it can be concuded that the rate of gain in strength of RHA mortar shown in Figure-4 primariy depends on w/(c+rha) ratio. 5.3 This study presents the effect of FA and RHA in 1:3 proportion cement mortar. Both FA and RHA are significanty affecting the mechanica property and performance of mortars. From the study, foowing concusion are drawn Cement when repaced upto 25% by FA contributes better strength and better performance in mortar mix of proportion 1:3. As the % of RHA increased in the mortar mixes, it wi ead to addition of water requirement from workabiity criteria and this increase in water content in mortar reduces the compressive strength of mortar. In a comparison of FA and RHA mortar mixes of proportion 1:3, FA mortar mixes show better resuts as compared to RHA mortar mixes in a the three aspects, compressive strength, water absorption and drying shrinkage test. Water absorption Figure-5 and Figure-6 show the water absorption of controed and FA mortar mixes and Figure-7 and Figure8 show the water absorption of controed mix and RHA mortar mixes. FA mortar S31 shows 5.55 % water absorption and is ower than that of controed mortar mix at 9 days age. A FA and RHA mortar mixes except S31 show higher water absorption resuts as compared with controed mortar mix at 28 and 9 days of age. A the FA mortar mixes having ess than 1% of water absorption; this indicates that FA mortar mixes are good mortar mixes. From Figure-7, as the percentage of RHA ISSN (Print) : , ISSN (Onine) : JREAS, Vo. 3, Issue 1, January 218

6 [9.] Up to 25% repacement of cement by FA, it was observed that the water absorption was marginay reduced. At 3% repacement eve it was more than the controed mix. This indicates that up to 25% repacement eve the contribution of FA in pore refinement due to secondary C-H-S formation is ceary visibe. [1.] S. A. Khadikar, Performance Characteristics of inter bended and inter ground fy ash Based Composite Cements A Comparative Assessment, Proceedings of Innovative Word of Concrete Pune, India, Sept. 23. The RHA significanty contributes towards owering shrinkage in masonry mortars; the effect of FA is just adverse. [11.] Mohan Prasad Arya, Cement Mortar Mixes and Their Strengths, Proceedings of Innovative Word of Concrete Pune, India, Sept. 23. References [1.] [2.] [3.] Pande A. M. & Gupta L. M. Masonry Mortars with fy ash as one of the ingredients A step towards sustainabe deveopment, Internationa Congress - Fy Ash India 25, 4-7 December 25 New Dehi, fy ash Mission TIFAC. [12.] IS 456:2 Indian Standard, Pain and Reinforced Concrete Code Of Practice [13.] IS195:1987 Indian Standard, Code of Practice for Structura Use of Unreinforced Masonry M. Akram Tahir, M. Sabir, A study on durabiity of fy ash-cement mortars, 3thConference on Our Word in Concrete & Structures: August 25,Singapore [14.] IS 225:1981 Indian Standard, Code of Practice for Preparation and Use of Masonry Mortars [15.] IS 383:197 Indian Standard, Specification for Coarse and Fine Aggregates from Natura Sources for Concrete Mohamed A. Aboubakar, Eshmaie Ganjian, Homayoon Pouya, A. Akashi, A Study on the Effect the addition of thermay treated Libyan Natura Pozzoan has on the Mechanica Properties of Ordinary Portand Cement Mortar, Internationa Journa of Science and Technoogy, Voume 3 No.1, January 213, ISSN [4.] O. Cizer, K. Van Baen, D. Van Gemert, J. Esen, Carbonation and hydration of mortars with cacium hydroxide and cacium siicate binders [5.] M.J. Mosquera, T, B. Siva, B. Prieto, E. RuizHerrera, Addition of cement to ime-based mortars: Effect on pore structure and vapor transport, Cement and Concrete Research 36 (26) [6.] Cengiz Duran Atis, AaettinKiic, Umur Korkut Sevim, Strength and shrinkage properties of mortar containing a nonstandard high-cacium fy ash, Cement and Concrete Research 34 (24) [7.] M.P. Seabra, H. Paiva, J.A. Labrincha, V.M. Ferreira, Admixtures effect on fresh state properties of aeria ime based mortars, Construction and Buiding Materias 23 (29) [8.] A. Izaguirre, J. Lanas, J.I. Avarez, Ageing of ime mortars with admixtures: Durabiity and strength assessment, Cement and Concrete Research 4 (21) ISSN (Print) : , ISSN (Onine) : Eva Vejmekova, Martin Keppert, Pava Rovnanikova, Zbynek Kersner, Robert Cerny, Appication of burnt cay shae as pozzoan addition to ime mortar, Cement & Concrete Composites 34 (212) [16.] IS 1727:1967 Indian Standard, Methods of Test for Pozzoanic Materias [17.] IS Indian Standard, Specification for fy ash for Use as Pozzoana and Admixture [18.] ASTM C 157/C 157M 8 Standard Test Method for Length Change of Hardened HydrauicCement Mortar and Concrete [19.] ASTM C Standard Test Method for Drying Shrinkage of Mortar Containing Hydrauic Cement [2] ASTM C642, standard test method for density, absorption and voids in hardened concrete, American Society for Testing and Materias: JREAS, Vo. 3, Issue 1, January 218