@article{oai:kitami-it.repo.nii.ac.jp:00006739,
 author = {Hiroshi, SAKURAI and Koichi, AYUTA and Noboru, SAEKI and Hiroshi, SAKURAI and Koichi, AYUTA and Noboru, SAEKI},
 issue = {2},
 journal = {北見工業大学研究報告},
 month = {Feb},
 note = {application/pdf, In this research， the strength of mortar specimens made during construction of Otaru　port were analyzed.　The experiment was planned and initiated by Dr.Isami HIROl in the　19th century.　The purpose of this study is to research the long-term strength and durability of mortar　specimens.　The results of these long-term experiments carried out with various internal　factors(type of cement， type of fine aggregate， type of volcanic ash, water cement ratio)and　external factors (age and exposure conditions such as in water,  in air，and in sea water)are　analyzed.　　　　The long-term mortar strength test can be summarized as follows : ?tensile strength is　affected by water-binder ratio， water-cement ratio， cement proportion， and volcanic ash　proportion.　?the reliability of not declining the tensile strength of age 28 days was 52 ％，that of 3 months ； 5 ％，and that of 1 year ； nearly 0 ％ at the age 80 years.},
 pages = {85--98},
 title = {Analysis and consideration on results of long term mortar　strength test},
 volume = {28},
 year = {1997}
}