海洋黏细菌对砂浆渗透性和微观结构影响

Effect of Marine Mucus Bacterium on Permeability and Microstructure of Mortar

研究了黏细菌对砂浆渗透性和砂浆表面微观结构的影响.砂浆试件分别浸泡于灭菌海水、2216E液体培养基和接入的黏细菌2216E液体培养基浸泡液中154d.利用测试距砂浆表面不同深度处的氯离子含量和浸泡液的pH值来评价微生物对砂浆渗透性的影响.结果表明:黏细菌对氯离子渗入砂浆有阻碍作用并能减少砂浆内部OH-的溶出;经接入黏细菌的2216E液体培养基浸泡后,砂浆表面覆盖有一层布满杆状细菌的膜层,该生物膜层可能是抑制浸泡液中氯离子渗入砂浆内部和阻碍砂浆内部OH-层渗漏的主要因素.

Effect of mucus bacterium on the permeability of mortar and the microstructure of mortar surface was investigated. Mortar samples were separately immersed in sterilized seawater, 2216E culture medium and 2216E culture medium containing mucus bacterium for 154 days. The chloride content in different lay ers of mortar and pH value of immersion solution were measured for evaluating effect of microorganism on mortar permeability. Experimental results indicate that the bacteria positively decelerates the penetration of chloride into the mortar and inhibites the dissolution of calcium hydroxide in mortar. The microstructure observation shows that a biofilm with rod-shaped bacteria is covered on the surface of the mortar sample immersed in 2216E culture medium containing mucus bacterium. Biofilms may be the major factor that in- hibits the chloride permeating into mortar and leaching out of OH- from mortar.