Base isolation pad

A device for absorbing energy to be positioned between two members which may vibrate or oscillate relative to one another due to forces applied to either one or both of the two members, which comprises:

• a first end plate member and a second end plate member, each end plate member engageable to one of the two members, the thickness of each of said end plate members being greater in the center than the thickness of said end plate member's outer perimeter;
• an energy absorbing means interposed between said first and second end plate members, said energy absorbing means having an inner section comprised of a substantially incompressible viscous fluid encapsulated by a resilient elastomeric outer section comprised of rubber;
• means for securing said energy absorbing means to each of said first and second end plate members;
• and
• a flexible reinforced tubular restraining shell surrounding said energy absorbing means and extending at least partially between said first and second end plate members, said restraining shell comprising at least one helical tensile load carrying section of high modulus material sandwiched between two flexible resilient sections made of a similar resilient elastomer, said reinforced tubular restraining shell and said first and second end plate members defining a container for restraining said resilient elastomeric energy absorbing means yet at the same time allowing said energy absorbing means to vibrate and deform when force is applied thereto, and in addition said restraining shell in conjunction with said energy absorbing means capable of functioning as a support.

An energy absorbing device adapted to be positioned between two members which may vibrate or oscillate relative to one another, which comprises:

• a first end plate member and a second end plate member, each end plate member engageable to one of the two members;
• an energy absorbing means interposed between said first and second end plate members, said energy absorbing means having an inner section comprised of rubber without curatives encapsulated by a resilient outer section comprised of rubber;
• means for securing said energy absorbing means to each of said first and second end plate members;
• a flexible reinforced tubular restraining shell surrounding said energy absorbing means and extending at least partially between said first and second end plate members, said restraining shell comprising at least one tensile load carrying reinforcement section at least partially imbedded within a flexible resilient elastomeric section, said resilient elastomeric section extending the full height of said shell, said shell in conjunction with said energy absorbing means capable of functioning as a support;
• a first layer of noncorrosive elastomeric material which has resistance to harsh environmental conditions, at least partially covering a surface of said first end plate member that is not secured to said energy absorbing means;
• and
• a second layer of noncorrosive elastomeric material which has resistance to harsh environmental conditions, at least partially covering a surface of said second end plate member that is not secured to said energy absorbing means.

In a resilient support device to be positioned between two members which may vibrate or oscillate relative to one another which comprises:

• a top and bottom end piece each engageable to one of the two members;
• an elastic core having at least one curved outer surface, the core interposed between the first and second end pieces;
• and a reinforced resilient elastomeric casing surrounding the curved outer surface, the improvement comprising:
• the elastic core comprising a substantially viscous inner section encapsulated by a resilient elastomeric section;
• and
• the reinforced resilient elastomeric casing is adapted for permitting the device to support a load yet allow the device to undergo limited deformation upon application of a force, the casing and the elastic core having no bond therebetween, and the casing to comprise:
• a resilient elastomeric section extending the full height of the casing;
• and
• a helical tensile load carrying member imbedded within said resilient elastomeric section, said helical tensile load carrying member wound at an angle that is 54.degree. up to 90.degree. from a direction parallel to the axis of said helical tensile load carrying member.