Emirates Journal for Engineering Research, 19 (3), 11-18 (2014) (Regular Paper) 11 A STUDY OF MUSA PARADISIACA PSEUDO-STEM PITH FLUID AS SET-RETARDING ADMIXTURE IN CEMENT PASTE AND MORTAR Akaninyene A. Umoh 1 and Samuel P. Nnana 1 1 Building Department, Faculty of Environmental Studies, University of Uyo, Akwa Ibom State, Nigeria (Received May 2014 and Accepted Oct. 2014) اﻟﻄﺎزﺟﺔ اﻟﻤﻮز ﻷوراق اﻟﺠﺬﻋﻲ اﻟﻠﺐ ﺳﺎﺋﻞ ﺗﺄﺛﻴﺮ دراﺳﺔ ﻋﻠﻰ اﻟﺒﺤﺚ هﺬا ﻳﻘﻮم واﻟﻤﻮرﺗﺮ اﻹﺳﻤﻨﺖ ﺧﺼﺎﺋﺺ ﻋﻠﻰ. ﻧﻄﺎق ﻓﻲ اﻟﺠﺬﻋﻲ اﻟﻠﺐ وﺳﺎﺋﻞ واﻟﻤﺎء اﻹﺳﻤﻨﺖ ﻣﻦ اﻹﺳﻤﻨﺖ ﺗﺤﻀﻴﺮﺧﻠﻄﺔ ﺗﻢ ﻟﻘﺪ0 - 1 % وﺗﻢ اﻹﺳﻤﻨﺖ وزن ﻣﻦ و اﻟﺘﻨﺎﺳﻖ أﺟﻞ ﻣﻦ اﺧﺘﺒﺎرهﺎ و اﻹﻋﺪاد ﻗﺖ. ﺑﻨﺴﺒﺔ اﻟﺮﻣﻞ ﻣﻊ اﻹﺳﻤﻨﺖ ﺑﺨﻠﻂ اﻟﻤﻮرﺗﺮ ﻋﻴﻨﺎت اﻋﺪاد ﺗﻢ ﻟﻘﺪ1 اﻟﻰ3 ﻣﻊ اﻹﺳﻤﻨﺖ اﻟﻰ اﻟﻤﺎء وزن ﻧﺴﺒﺔ ﺑﻨﺴﺒﺔ0.4 , ﺑﻨﺴﺒﺔ اﻟﺠﺬﻋﻲ اﻟﻠﺐ اﻟﺴﺎﺋﻞ ﻣﻊ0 - 1 % اﻹﺳﻤﻨﺖ وزن ﻣﻦ. اﻟﺘﺤﻘﻖ ﺗﻢ ﻟﻘﺪ ﻗﻮة ﻣﺜﻞ اﻟﺨﻠﻄﺔ ﺧﺼﺎﺋﺺ ﻣﻦ اﻟﻀﻐﻂ) اﻟﻜﺴﺮ ﻗﻮة( واﻟﻜﺜﺎﻓﺔ اﻟﻤﺎء واﻣﺘﺼﺎص واﻹﻧﺤﻨﺎء. أن ﻋﻠﻰ اﻟﻨﺘﺎﺋﺞ وآﺸﻔﺖ اﻹﺳﻤﻨﺖ ﻟﺨﻠﻄﺔ واﻟﻨﻬﺎﺋﻲ اﻷوﻟﻲ اﻹﻋﺪاد وﻗﺖ ﻣﻦ آﻞ ﻳﺄﺧﺮ اﻟﺠﺬﻋﻲ اﻟﻠﺐ ﺳﺎﺋﻞ. ﻗﻮة ﻗﻴﺎس ﺗﻢ آﻤﺎ اﻟﻀﻐﻂ) ﻗﻮة اﻟﻜﺴﺮ( ﻟﻌﻴ ﺑﻴﻦ ﻣﺎ ﺗﺘﺮاوح وآﺎﻧﺖ اﻟﻤﻮرﺗﺮ ﻨﺎت11.87 ﻳﻮﺗﻦ/ ﻣﻢ2 ﻓﻲ7 و أﻳﺎم22.87 ﻧﻴﻮﺗﻦ/ ﻣﻢ2 ﻓﻲ56 وﻗﺪ ﻳﻮم ﺑﻠﻐ اﻧﺤﻨﺎء ﻗﻮة أﻋﻠﻰ ﺖ3.52 ﻧﻴﻮﺗﻦ/ ﻣﻢ2 ﺗﺤﺘﻮى ﻣﻮرﺗﺮ ﻟﻌﻴﻨﺔ ﻋﻠﻰ75 % اﻟﺠﺬﻋﻲ اﻟﻠﺐ ﺳﺎﺋﻞ ﻣﻦ. ﻧﺘﻴﺠﺔ وآﺎﻧﺖ آﺎﻓﻴﺔ ﻏﻴﺮ اﻟﺠﺬﻋﻲ اﻟﻠﺐ ﺳﺎﺋﻞ ﻣﻦ ﻣﺘﻔﺎوﺗﺔ آﻤﻴﺎت ﻋﻠﻰ ﺗﺤﺘﻮى واﻟﺘﻲ اﻟﻤﻮرﺗﺮ ﻟﻌﻴﻨﺎت اﻟﻤﺎء اﻣﺘﺼﺎص, ﺑﻴﻨﻤ ﺎ آﺎﻧﺖ ﻣﻦ اﻟﺨﺎﻟﻴﺔ ﻧﻈﺎﺋﺮهﺎ ﻣﻦ أﻋﻠﻰ آﺎﻧﺖ اﻟﺨﺬﻋﻲ اﻟﺴﺎﺋﻞ ﻋﻠﻰ ﺗﺤﺘﻮى اﻟﺘﻰ اﻟﻤﻮرﺗﺮ ﻟﻌﻴﻨﺎت اﻟﻤﺸﺒﻌﺔ اﻟﻜﺜﺎﻓﺔ هﺬا اﻟﺴﺎﺋﻞ. اﻟﺠﺬﻋﻲ اﻟﺴﺎﺋﻞ اﺳﺘﺨﺪام أن إﻟﻰ اﻟﺪراﺳﺔ وﺧﻠﺼﺖ) ﺑﻨﺴﺔ اﻟﻰ ﺗﺼﻞ75 (% إﻋﺪاد ﻟﻮﻗﺖ آﻤﺜﺒﻂ إ اﻟﻤﻮرﺗﺮ ﺳﻤﻨﺖ ﻣﺜﻞ اﻹﻧﺸﺎﺋﻴﺔ اﻟﺨﺼﺎﺋﺺ ﺗﻌﺰز اﻟﻀﻐﻂ ﻗﻮة) اﻟﺨﺮﺳﺎﻧﺔ آﺴﺮ ﻗﻮة( و ﺗ اﻟﻨﻮع ﻣﻦ ﻣﻮرﺗﺮ اﻧﺘﺎج ﻋﻠﻰ ﺸﺠﻊ(M) اﻟﻌﺎم ﻟﻠﺘﻄﺒﻴﻖ. The study undertakes the effect of Musa Paradisiaca Pseudostem Pith Fluid (MPPPF) on cement paste and mortar. The cement pastes consist of cement, water and MPPPF in the range of 0 to 1% by weight of cement; and tested for consistency and setting times. Cement to sand mix of 1:3 with water-cement ratio of 0.4 by weight with MPPPF in the range of 0 to 1% by weight of cement was used for the production of mortar specimens; and properties investigated were compressive and flexural strengths, water absorption, and density. The results revealed that MPPPF delays both the initial and final setting times of the cement paste. The compressive strength values of the mortar specimens range between 11.87N/mm 2 at 7 days and 22.84N/mm 2 at 56 days. The highest flexural strength of 3.52N/mm 2 at was attained at 28 days with mortar specimen containing 0.75% MPPPF. The result of water absorption of varying contents of MPPPF was non-significant, while the saturated densities of the MPPPF test mortars were higher than those of the reference mortar. The study concluded that the use of MPPPF (up to 0.75%) as set- retarder in cement mortar enhance the structural properties such as compressive strength towards the production of type ‘M’ mortar for general application. 1. INTRODUCTION When cement is mixed with water, a sticky paste is formed which remains plastic for a short period. With the passage of time, the plasticity gradually disappears and the cement paste becomes stiff due to initial hydration of cement. This means that silicate and aluminate minerals in the cement react and combine with water to produce the “glue” that holds together the aggregate which forms the mortar. A delay in the setting of cement paste can be achieved by adding a retarder to it. Retarders generally slow down the hardening of the cement paste by stopping the rapid set shown by tricalcium aluminate but do not alter the composition of hydration products. Retarders can be classified into Setting retarders and Hardening retarders. The main purposes of setting retarders are in delaying setting time and to offset the accelerating effect of high ambient temperature (hot weather), to keep the mortar or concrete workable throughout the entire transport, placing and finishing periods. This is particularly important when transporting concrete over large distances, and for the elimination of cold joints and discontinuities in large structural units, and to prevent setting of the concrete in the truck in case of delay[1]; whereas, the main purpose of hardening retarder is the delaying of the strength development by decrease in the rate of heat evolution and thereby lowering the maximum temperature to a level where thermal cracks pose less problems[2]. Therefore, hardening retarder can be defined as an Admixture which decreases (instead of increases) the rate of development of early strength in the mortar or concrete, with or without affecting the setting time.