CHAPTER ONE

1.0 INTRODUCTION

1.1 Background of Study

There   is   need   for   affordable   building  materials  in  providing adequate housing for  teamingpopulace   of  the   world.   The  cost  of   conventional   building   materials  continue   to  increase  asmajority of the population continues to fall below the poverty line. Thus, there is the need tosearch for local materials as alternatives for the construction of functional but low-cost buildingsin both the rural and urban areas. Some of the local materials that have been used as earthenplaster (Svoboda and Prochazka, 2012), lateritic interlocking blocks (Raheem et al.,  2012) andpalm kernel shell (Raheem et al., 2012). Continuous generation of   waste   arising   from industrial by-products  and agricultural  residue,create   acute   environmental   problems   both   in   terms   of   their   treatment   and   disposal.   Theconstruction industry has been identified as one that absorbs the majority of such materials asfiller in concrete. If these fillers have Pozzolanic properties, they impart technical advantages tothe resulting concrete and also enable larger quantities of cement replacement to be achieved.Wastes can be  defined   as  by-products of agricultural   farm   produce  and industrial processeswhich do not essentially have anything to do with the building, but with special processing andtreatment or in conjunction with other materials, can economically substitute (or even improvethe quality of) convention building materials (Raheem et al., 2012).Sawdust is a waste material from the timber industry. It is produced as timber is sawn into planksat saw mills located virtually at all the major towns in the country. This process is a daily activity1

causing heaps of saw dust to be generated after each day. In order to overcome these problems ofdisposal, method of recycling and re-use of the materials by burning them into ashes and used asbuilding and construction materials have been developed. This is beneficial because it could beused to partially replace cement thereby bringing down the cost of construction. The need to convert this waste product into useful by-products is the focus of this study.1.2 Justification of StudyPortland cement  is  generally  associated   with high  cost  and   short supplies;  its  production  iscapital intensive and environmentally unfriendly. For these reasons, using materials like sawdustash  as   partial  replacement   materials   for  cement  will   reduce  the   cost   of   production,   cost   oftransport, pollution and saving of the energy required to produce cement.More also, the intension to use sawdust ash as partial replacement materials for cement comesfrom the fact that the material are abundant and cost nothing since they are dumped at the timbershades as wastes.1.3 AimThe research shall seek to find out the mineral composition of saw dust ash and further test it as a cementreplacement alternative. The research shall also seek to find out the optimum mix design for the use ofsaw dust ash as a partial replacement of cement. This study shall positively contribute to future advances in green cement production in which theuse of limestone will have been reduced or eliminated altogether.2

1.4 Objectives of study. The objectives of this research study are as follows:(i) To study the effect of sawdust ash on compressive strength of concrete (ii) To analyze the  properties of the  saw dust ash  concrete as compared  to Portland cement(iii) To study the physical and mechanical properties of saw dust ash blended withcement in various mix proportion in mortar and concrete production.(iv)To evaluate the effect of sawdust ash on the setting time of cement paste(v) To evaluate the pozzolanic activity index of sawdust ash