[55] If an excessive amount of air becomes trapped from the concrete due to the mixing method, defoamers can be used to persuade the air bubble to agglomerate, rise for the surface of the wet concrete and after that disperse. Their skepticism was reinforced with the Cass Report from Britain, https://ariabookmarks.com/story5516435/an-unbiased-view-of-concrete-reinforced-retaining-wall