Ảnh hưởng của độ nhớt hồ chất kết dính tới cấu trúc của bê tông rỗng thoát nước

Abstract

Pervious concrete is a new material that has been widely applied in construction such as: road surface coating, parking lot, amusement park, etc. However, the selection of material composition, forming process still has some problems such as: large quantity of binder pastes which causes to seal the pores at the bottom layer of concrete, distribution of pores is uneven depending to the height of sample, etc. To solve the above problems, this research used binders composing of cement, 10-30% of silica fume and fly ash by weight of binder with the water/binder ratio of 0.2; 022; 0.24 to adjust the binder viscosity. With the viscosity of the CKD lake in the range (19-354) mmPa.s, the largest thickness of the CKD lake wrapped around the aggregate is determined, with aggregate (5-10) mm having a thickness of (0.243-0.710) mm, with aggregate (10-20) reaching a thickness of (0.297-0.821) mm, and the porosity distribution was also analyzed according to the sample height by using ImageJ software The author assessed the porosity distribution according to the height of the NRR corresponding to the viscosities of the CKD lake 19, 31 and 69 mmPa.s. This is the basis for designing pervious concrete and selecting the appropriate forming mode.