伊太利の火山灰と火山灰セメント及び火山灰ポルトランドセメント (其2)

抄録

In continuing the previous study, the authors reported in the present paper the results of further studies on Italian and Japanese puzzolanas and puzzolanic Portland cements. The brief summeries are abstracted from the original Japanese paper, as following:
(1) Three Italian puzzolanas, which were sent from Dr. C. Vittori, Società Anonima Italiana, Per la Produzione Calci e Cementi di Segni, Roma, Italiana, two Japanese puzzolanas, one siliceous earth (Keisan-Hakudo), one spent shale, and two blast furnace slags were compared on their specific gravities, chemical compositions, etc. The results are tabulated in the following tables.
Table 1. Results of Total Analysis
Table 2. Results of Specific Gravity and Soluble Analysis by 10%-NaOH and 5%-HCl Solutions
(2) These Italian and Japanese puzzolanic materials were mixed with Portland cement and ground intimately to various puzzolanic Portland cements. These samples were compared on their physical properties and chemical compositions, as shown in the following table 3.
(3) These samples of (1) puzzolanic Portland cements and (2) puzzolanic lime cements were compared on their hydraulic properties of mortar strength by the special testing method of compressive strength, which had been proposed by the present author (S. Nagai, Journ. Soc. Chem. Ind., Japan, 1929, 32, 635, 641; 1930, 33, 129; 1931, 34, 290; Tonindustrie=Zeitung, 1929, 53, 1048) and composed from small cylindrical testing piece (Dia. 2cm and Length 3cm), and used 1:3-cement sand mortar of high water-cement ratio (w/c=0.60-0.70) or so-called plastic mortar for moulding. The results were obtained in the following table 3.
Tabl. 3. Results of Compressive Strengths by Plastic Mortar Moulded to Small Cylindrical Test Pieces
(4) Again, these Italian and Japanese puzzolanic materials were mixed with slaked lime and ground intimately to puzzolanic lime cement. These cement samples were also compared on their physical properties and chemical compositions, as shown in the following table.
Table 4. Mixing Proportions, Physical Properties and Chemical Compositions of Italian and Japanese Puzzolanic Portland Cements and Puzzolanic Lime Cements
(5) These samples of (1) puzzolanic Portland cements and (2) puzzolanic lime cements were also compared on their soundness or expansion in the course of hardening by the methods of Lechatelier's calliper and Bauschinger's apparstus. From the results, it was observed that puzzolanic Portland cements are bettter or have smaller expansion than puzzolanic lime cements.
In conclusion, the suthors wish to express their hearty thanks to Prof. G. Malquori, Instituto Chimico, Roma Universita, Catania, Italiana and Dr. C. Vittori, Società Anonima Italiana, Per la Produzione Calci e Cementi di Segni, Roma, Italiana, for the kind sending of Italian puzzolanas and puzzolanic Portland cements.