In order to study the influence of trowel finishing specifications on surface strength of floor concrete, we measured the abrasion and scratch resistance of floor concrete samples finished by several specifications. As a result, we showed some instances of different surface strength of floor concrete caused by differences of finishing specifications despite the same mix proportion. And we studied the relationship between quantity of absorbed surface water and penetration resistance at the time of finishing and surface strength, and showed the possibility of the presence of the best finishing time in surface strength and of making a judgement of the best finishing time by the quantity of absorbed surface water.
