SEISHIN Co., Ltd is the General agency for SP seismic base isolation system and bD-pile in the Kanto(Tokyo,Kanagawa,Chiba,Saitama) region.

Joint Research and Development

  • Prof. Gun Buntala Sthenly, Lab. of computer methods in applied mechanics and engineering, Dept. of Architecture, School of Engineering, Nihon University.
    (Development of Calculation of the efficiency of SP Aseismic method and response analysis)
  • Kato Tribology Laboratory, Dept. of Mechanical Engineering, School of Science and Technology, Nihon University, Tokyo.
    (Development of pile-cap connection for the SP seismic base isolation system.
    Research for frictional resistance reduction among steel piles, concrete foundation and ground soil)

Questions & Answers

  • What are the height and size limits for the building on the SP seismic base isolation system?

    1 to 5 story buildings are ideal to make our base isolation system most cost-effective. It can be applied to buildings up to 3,000m²

  • What is the lifespan of the bD-piles (steel pipe piles) for SP method? How do they rust?

    Over 10 years of research and experiments on steel corrosion done by Professor Ohsaki at Tokyo University concluded that steel in soil will be affected by corrosion not more than 1mm in 50 years.
    Building Standard Act of Japan also indicates that the loss of thickness caused by corrosion and rust for structural steel in soil would be 1mm.
    Based on those research and regulation, our steel pipe piles are designed with 1~2mm extra thickness for corrosion protection.
    Our steel pipe piles are made of JAS(Japanese Industrial Standard) STK400 steel.

  • Any warranty?

    Japan Blade-Pile Association warrants the performance of bD-pile and blade-pile for 20 years from the date of completion.
    If, within the term of the warranty, the structural integrity of system becomes  compromised due to product deterioration or quality of manufacturing workmanship or material, Japan Blade-Pile Association will adjust and/or furnish new product as replacement for the defective product. The expenses for the adjustment and/or replacement will be covered by the Product Liability Insurance up to 50,000,000 yen.

  • Are there any constraints on choice of building structure or its design?

    There is no constraint on building structure and its design. SP seismic isolation system can be applied to buildings with any structural systems (Wood, Concrete and Steel).

  • How does the steel pipe piles work as seismic isolation system?

    Taking the full advantage of elasticity and tenacity of steel pipe pile, the bD-pile is designed to control natural periods of the structure. Through the analysis of building weight/structure and soil condition, we calculate proper numbers and placements of bD-piles for the best performance. Integrating piles with building and its foundation system as a whole, the SP seismic isolation system achieves effective performance against earthquake.

  • How should the base isolation system be designed?

    All calculation and design for the system will be done by JAPAN Blade Pile Association based on construction documents (plans, elevations etc.) and the soil-test reports of your site.

  • Does SP seismic base isolation system work for a building on soft soil condition?

    Absolutely. The SP base isolation system performs more effectively in the soft soil condition.

  • How much does it cost as a seismic isolation system?

    The cost of installation varies widely depending on the size of buildings and geological condition of the site, so please feel free to contact us to get fee-estimate.
    If your site condition requires soil/ground improvement before new construction, the SP isolation system becomes really cost-effective because it not only performs as base isolation system but also provides ground/soil improvement solution.

  • What type of foundation should be selected for installing SP seismic base isolation system?

    It should be mat foundation to achieve maximum performance.

  • What is the difference between conventional seismic resistant structure and seismic isolation system?

    Conventional seismic resistant structures are designed to endure earthquakes by increasing the rigidity of building by adding shear walls or braced frames. On the other hand, the seismic isolation system is a flexible approach for isolating the structure from the ground, reducing seismic shock propagation into the structure.
    In addition to reducing the structural damage of building, the seismic isolation system also minimizes seismic effect and prevent any serious injuries to people inside of the building.

  • Are there any other devices necessary besides steel pipe piles for SP seismic base isolation system?

    Although the way of constructing concrete foundation is slightly different from conventional one, nothing else is needed for SP seismic base isolation system besides our steel pipe piles. Since our isolation system doesn’t require any expensive isolation devices, it is more cost-effective compared to other base isolation systems.

  • Is it possible to apply the SP seismic base isolation system in hard-soil site which doesn’t really require ground/soil improvement?

    Yes. We are able to install our system by adjusting the way of installation.

  • How long does the installation take?

    It will only take 1-2 days for the pile installation (for a standard house)

  • What kind of steel pipe piles are used in the SP seismic base isolation system?

    We use “bD-pile” or “blade-pile” for the SP base isolation system. The performance and safety of both piles are officially approved by Ministry of Land, Infrastructure and Transport of JAPAN.

  • Is there any specific way of installation for water pluming or gas piping?

    In terms of water pluming and gas piping, we need some special way of installation.

  • Regarding subsidence repair with the PUBB method, is it necessary to move temporary out of home during installation?

    Although we might have to make some changes in pluming and piping systems, residents don’t have to move temporary out of their home.

  • Does PUBB method generate noise and vibration during the installation?

    No. Since our piles are screw-in piling and ground anchoring system, those can be installed quickly with minimal noise and vibration.

  • Does your installation require large workable space or storage space for installation and equipment?

    Not really. We have experienced installation with limited workable space many times.
    Watch the Video “TUF News Fukushima”.

  • Is there possibility of subsiding again?

    Since the piles are anchored to the supporting layer (bedrock), there is no risk of subsiding again.

  • How much does it cost for repairing?

    It depends on the extent of damage and repair, so contact us to get free estimate. It is definitely effective and cost-efficient compare to any other repairing method.

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