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土の弾塑性構成モデルに必要な土質パラメータを等体積一面せん断強さから決定することを目的として, 各地から様々な不撹乱粘性土試料を集めて等体積一面せん断試験を実施した. この実験結果と弾塑性構成モデルから導かれた等体積一面せん断強さの理論式とを比較した. 計算には, 関口と太田が提案した構成モデルを用いたが, 絶対値としての実験値と理論値 (経験式によるパラメータを用いた理論値) には相当な差があることがわかった. これは時間依存性の影響であると考えられるため, 等体積一面せん断強さの時間依存性を実験的に調べ, その影響を定量的に評価した.

To evaluate a Ni-43.5wt%Ti alloy as a new alloy for cast clasp, the fatigue properties of its castings were examined and compared with those of Co-Cr and Type IV Au alloys castings. The Ni-Ti alloy was cast into a phosphate-bonded investment mold using an argon-arc melting and pressure casting machine. The Ni-Ti alloy castings showed superelasticity in bending tests. Fatigue tests were carried out by an originally designed machine under bending in one direction on the cantilever at constant set deflection. The fatigue-proof of Ni-Ti alloy was more excellent than those of Co-Cr and Type IV Au alloys.

A Ni-45 wt% Ti (Ni-50 at % Ti) alloy was cast into molds of magnesia and silica investments by use of a dental argon-arc pressure casting machine with a copper crucible . The castings exhibited shape memory properties. The shape recovery process was sharper in the specimens cast in magnesia investment molds than in those cast in silica (phosphate-bonded) investment molds. The latter casting had a hard region of the periphery, suggesting that shape recovery process may be affected by reaction of molten metal with silica. Furthermore, the alloy possessed the adequate mechanical properties for consideration as crown-and-bridge prostheses.