Journal of Multidisciplinary Engineering Science and Technology (JMEST) ISSN: 2458-9403 Vol. 4 Issue 6, June - 2017 www.jmest.org JMESTN42352249 7480 Effects Of CONPLAST SP 430 Superplasticizer Using Four Nigerian Produced Cements Individually In Concrete Production For Highway Pavement Isaac Akiije Department of Civil and Environmental Engineering Faculty of Engineering, University of Lagos, Akoka, Yaba, Lagos, Nigeria Abstract—The purpose of this study is in the consideration of using CONPLAST SP430 superplasticizer upon attainment of desirable strength of concrete and optimizing same for highway pavement using four different new types of cement produced in Nigeria. In the facet, one normal cement type tagged 42.5Np and three rapid cement types tagged 42.5Rd, 32.5Rs and 32.5Rt were individually mixed with granites, sand and water plus CONPLAST SP430 superplasticizer for the production highway cement concrete pavement. Individual mixture was at a very low water-cementitious material ratio (w/cm) of 0.32 and concrete mix ratio of 1:1.5:3. Cement tests included specific gravity, fineness, consistency, setting time, chemical and metallic compositions. Tests carried out on the fine and coarse aggregates used included particle size distribution, specific gravity, chemical and metallic compositions. Laboratory tests that were also carried out on the coarse aggregate included crushing, impact and abrasion. Tests carried out on fresh concrete included slump and compaction factor while those on hardened concrete were compressive, tensile splitting and flexural strengths. At 28 days curing age, each of the compressive strength value for the concrete specimens produced based upon the four cements used are respectively 26.67 N/mm 2 , 25.63 N/mm 2 , 25.56 N/mm 2 and 25.11 N/mm 2 . The concrete specimens’ tensile splitting strength values are respectively 2.78 N/mm 2 , 2.48 N/mm 2 , 2.10 N/mm 2 and 1.89 N/mm 2 while that of the flexural strength amounts are respectively 5.274 N/mm 2 , 4.208 N/mm 2 , 4.208 N/mm 2 and 3.496 N/mm 2 for the cements used. The significance of this study is that although the required compressive and tensile splitting strength values are not satisfied, the flexural strength value is satisfactory for highway pavement only by cement tagged 42.5Np. The justification for this research is in identifying the newly Nigerian made cement among the readily available ones to produce enhanced concrete at a cheaper economy and satisfying the required standard strength specification for highway pavement design and its construction. Keywords—Superplasticizer, Pavement, Consistency, Aggregates, Strength, Durability 1. INTRODUCTION Failure of rigid pavement is a great concern of which using superplasticizer to provide workable and appropriate consistency of fresh concrete at less water content and of a low permeability and high strength is a possible answer. Attempts have been made by many researchers upon increasing the strength and durability of concrete in relationship to workability. Falade (1999) researched on the effects of separation of grain sizes of fine aggregate on properties of concrete containing granite fines upon seven grain size ranges of granite fines with consideration to investigating appropriately their workability, density, compressive and flexural strengths. He concluded that the compressive and flexural strengths and density of the concrete produced increased with decreasing grain sizes, while the workability decreased with decrease in grain sizes. Akiije (2016) considered the effects of using 0.5, 0.55 and 0.6 water cement ratio separately with a Nigerian grade 42.5R portland cement. He remarked that fine and coarse aggregates, 42.5R Portland cement and water used are useful material for the production of concrete. However, he discouraged the use of 1:2:4 mix with individual water cement ratios 0.5, 0.55 and 0.6 while producing sustainable rigid pavement to ensure prevention of premature failure of public and private highway pavements. King (2007) considered supporting a sustainable future with microsilica concrete while using silica fume to enhance the properties of high performance through plastic properties, strength and durability. It was concluded in the research that microsilica can be used to produce high strength and high performance concrete provided that a suitable admixture is incorporated into the mix to reduce water content whilst ensuring adequate workability. Admixture such as superplasticizer is an ingredient other than Portland cement, water and aggregates that are associated with the production of concrete for increasing strength and durability. Mamlouk and Zaniewski (2006) claimed that superplasticizer is a high-range water reducer whilst greatly increases the flow of the fresh concrete or reduces the amount of water required for a given consistency. They further claimed that superplasticizer is capable of providing a low water-cementitious materials ratio that is beneficial with early strength gain, high-strength