The objectives of this research are to study the production step proper ratio physical properties mechanical properties and thermal insulation of concrete blocks mixed with waste ceramic powder. The ratios of concrete block mixed with waste ceramic powder include Portland cement type1: quarry dust: waste ceramic powder equal to1: 6.8: 0.2 1: 6.7: 0.3 1: 6.6: 0.4 1: 6.5: 0.5 and1: 6.4: 0.6 by weight. Water per cement ratio are 0.6 by weight. The concrete block samples were castedby the general production as same as the ordinary concrete blocks and were tested follow TIS.58. From the results the best amount of waste ceramic powder which put into concrete block is 1: 6.7: 0.3 of ratio. The proper ratios of waste ceramic powder can decrease the density or weight and increase the thermal insulation efficiency of concrete blocks. However the high amounts of waste ceramic powder effect to decrease the mechanical properties concrete blocks that are lower than TIS.58 standard.

The purpose of this research is to study the effect of a safety system provided for column reinforcement activity on productivity by studying a construction of buildings in Bangkok. The safety system composed of (1) stable scaffolding system (2) providing clean and not slip walkways on the scaffold (3) installation of handrails not less than 0.90 meters in height (4) installing stairs and (5) providing personal protective equipment for workers. Cost of the safety system is 40030 baht for a column reinforcement area of 40 numbers. Productivity rates for prior and after the used of safety system are 11.06 and 8.80 kg./person/hr. respectively. The productivity declines for approximately 20.43 % the working time for column reinforcement could take longer for 13.18 % and labor cost could increase for 13.32 %.