| 摘要 |
PURPOSE:To prove simply and rapidly the presence and absence of the fluidizing agent at a working site by taking up the supernatant liquid by diluting a fluidized concrete sample by water, making the supernatant liquid acidic, then shaking violently the supernatant liquid by adding or without adding a specified bubble retaining agent, and then measuring the continuance time of the bubbles on the liquid surface. CONSTITUTION:A small quantity of fluidized concrete sample is picked up, diluted to 5-20 times and mixed, the supernatant liquid after the sedimentation of the solid part is taken up, or an acid such as sulfuric acid is added to the filtrate filtered by a filter paper or cotton, etc. to make it acidic and the color of the solution is vanished to make the solution easy to observe. The one part of the solution is fed into a test tube, shaken violently and allowed to stand. If the fluidizing agent consisting essentially of lignin sulfonic acid salt is present, the bubbles are continued for >=5min, but if the agent is not present the bubbles are little and disappear suddently. If an organic solvent lighter than water and not mixed with water such as toluence, machine oil and powder such as talc are added as a bubble retaining agent to the supernatant liquid and the filtrate and bubbled similarly, the bubbles are continued for >=30min in case of the presence of the fluidizing agent, and disappear suddenly in case of the absence. The fluidizing agent can be determined semiquantiatively by the disappearing time of the bubbles. |
