Ritthichai Doncharee creator Pennung Warnitchai Chairperson Sun Sayamipuk Co-chairperson Thanakorn Pheeraphan Examination Committee Raktipong Sahamitmongkol Examination committee Thailand (HM King) Scholarship donor text series technical report th Pathum Thani, Thailand Asian Institute of Technology 2009 continuing eng 56 leaves : ill. Due to global warming, the cement manufacture is one of several industries which affect to that. Therefore, the use of limestone powder as constituent material in producing cement is significantly needed in eliminating milling process. The purpose of this study is to investigate the influence of limestone powder and fineness of Portland limestone cement (PLC). Control cement and nine PLCs which used in this study were produced by inter-grinding method of clinker, limestone powder and some amount of gypsum by a ball mill of 5 kg capacity. Control cement and PLCs which are different in limestone content of 10%,20% and 30% and fineness of 3,500,4,300 and 5,000 cm²/g were obtained and tested to investigate its properties, namely physical properties of cement, mechanical properties and durability properties. In order to achieve the same consistency, the water binder ratio was kept constant at 0.45. Sand to binder ratio was 2.75. Based on the results, limestone was found can be used as a cement replacement material in order to produce PLC by inter-grinding method. In grinding process, the increase of percent replacement of limestone powder can reduced the grinding time of PLC to achieve the target fineness. Considering the cement properties, the setting time of PLC was reduced when the limestone content and fineness of PLC increased. The heat of hydration was contributed not only by increasing percent limestone replacement but also from the fineness effect of PLC. Limestone powder has more effect in the compressive strength. This is due to the filler effect of limestone powder which can improve packing of the particles and lead to increase the compressive strength. However, the increase of limestone content lead to decrease the compressive strength. In the same way, the increase of fineness of PLC the strength was also decreases. In terms of drying shrinkage the magnitude of length change of mortar containing was sharply decreased, but it then increased when the fineness of PLC increased. For the water permeability of PLC mortar, the use of Jim est one powder replacement can be reduced the water penetration as well as when the fineness of PLC increased. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Structural Engineering, School of Engineering and Technology Thesis (M.Eng.) - Asian Institute of Technology, 2009 Portland cement Limestone industry Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B03975 http://203.159.5.9/ait-thesis/detail.php?q=B03975 100107 20260818090613.0