Patents Assigned to S: Kajima Corporation
  • Patent number: 4676693
    Abstract: A method and apparatus is provided to embed paper drain material in water-laden soil by means of a mandrel driven into the soil by power means. The paper drain material is intermittently treated with a substance detectable by a signal emitted electronic sensing means secured to the lower end of the mandrel. When the paper drain is believed to be in place, the mandrel is withdrawn. During mandrel withdrawal, as each sensing means passes by each detectable substance, the signal from the sensing means is modulated, thereby indicating that the paper drain is embedded in place and the mandrel has disengaged from the paper drain. If the paper drain adheres to the mandrel and is being withdrawn with the mandrel, no modulated signal will be generated, thereby indicating that the paper drain is not properly anchored in the soil.
    Type: Grant
    Filed: November 30, 1984
    Date of Patent: June 30, 1987
    Assignees: S: Kajima Corporation, Fudo Construction Co., Ltd., Nitsushin Soil Consulting Corporation
    Inventors: Toshio Hiroshima, Mamoru Tamura, Mikio Sakaizumi