Investigation On Some Techniques Related To Preparation Of Foamed Concrete

Techniques of foamed concrete were investigated, including synthesis and modification of foaming agent with high grade, compatibility between foaming agent and foamed concrete, and preparation of foamed concrete with good performance.The synthesis and modification of the protein type and the rosin type foaming agent for the preparation of foamed concrete were investigated first. The optimum condition for synthesizing the two type foaming agent was established based on the analysis of the factors which determine the synthesis process, foaming ability and the foam stability. The rosin typeⅡfoaming agent was recommended as an appropriate one for the preparation of foamed concrete.Processes of Ca(OH)2 hydrolysis, NaOH hydrolysis and Ca(OH)2-NaOH hydrolysis for the synthesis of foaming agent were investigated, and the Ca(OH)2 hydrolysis process was found to produce foaming agent with better foaming ability and foam stability by boiling the mixture with proportion of water 250g, cattle hoof powder 25g, calcium hydroxide 3.5g and sodium hydrogenous sulfite 1g. Modification on the protein type foaming agent synthesized by Ca(OH)2 hydrolysis process attempted with addition of several chemicals and surfactants. Results showed that the foam stability was improved with addition of 0.3~0.5% triethanolamine, and both foaming ability and foam stability were improved with the addition of 0.7～1.3% alkyl benzene sulfonate, and it was also true with the simultaneous addition of 0.7% alkyl benzene sulfonate and 0.3～1.0% triethanolamine.The synthesis condition of the rosin type foaming agent was optimized by means of orthogonal test with the addition of hydrolyzing agent F and hydrolyzing agent F respectively as alkali hydrolysis media, as a result, two foaming agent named as rosin typeⅠand rosin typeⅡwere obtained. Foaming test results according to manual vibration method showed that rosin typeⅠfoaming agent was better than rosin typeⅡ. The foaming ability and foam stability of originated from protein type and rosin typeⅠand rosin typeⅡwere further evaluated by means of compressed air foaming method, and the results showed that the foaming ability and foam stability last time were found to be 60 times and 200min respectively for the protein type foaming agent, and 412 times and 180min for rosin typeⅠfoaming agent, and 275 times and 250min...