| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a musical instrument which is increased in mass and of which centroid is fixed by fixing a part of bamboo by using a flowable cement paste in place of threads and cords used at the time of manufacturing a bamboo musical instrument. SOLUTION: A part of the bamboo 1 is fixed by using a flowable cement paste 7 in place of the threads and cords used at the time of manufacturing bamboo musical instrument. While the compsn. of a cement-based material consists of at least ordinary cement, fine aggregate (silica sand is preferably to be fine powder of <=#7 and active silica is to be superfine powder), a cement fluidizing agent (preferably a non-AE system), a polymer emulsion and water, other materials may be incorporated therein at need. The ratio of the fluidizing agent to the cement of this compsn. is preferably 0.1 to 0.2%, the ratio of the fine aggregate 0 to 300% and the ratio of the polymer emulsion 10 to 20%, respectively. Water is preferably to be irreducible minimum within a possible range while considering workability and the ratio thereof to the cement is adequately 10 to 40%.</p> |
