Abstract
During construction of the north breakwater of the port of Otaru, Dr. HIROI conducted tensile strength tests using various types of mortar briquettes. This paper presents material research conducted concerning these tests Dr. HIROI conducted, as well as clarifies the background, place of commencement, purpose and period of testing. We also began to investigate the size, characters on the surface and markings of all the HIROI briquettes (mortar briquettes produced under the guidance of Dr. HIROI) kept at the Otaru Port and Harbour Office. This paper reports on an overview of a comprehensive study concerning the briquette, which was initiated to clarify the details of the tests conducted under the guidance of Dr. HIROI.
