Reinforcement material and reinforcement structure

A reinforcement material for reinforcing an object comprising:

• a resin layer containing a resin component and a foaming agent and becoming a reinforcement layer for reinforcing the object, and
• a restraining layer disposed on the resin layer, wherein
• the resin component contains a thermosetting resin and a rubber,
• a ratio of the thermosetting resin with respect to 100 parts by mass of the rubber is more than 100 parts by mass,
• the thermosetting resin contains a flexible epoxy resin and an epoxy resin other than the flexible epoxy resin,
• a ratio of the flexible epoxy resin in the thermosetting resin is 10% by mass or more and 45% by mass or less,
• the rubber contains an acrylonitrile-butadiene rubber,
• a ratio of the acrylonitrile-butadiene rubber with respect to 100 parts by mass of the flexible epoxy resin is 60 parts by mass or more,
• the reinforcement layer contains a matrix resin obtained by curing the resin component and a plurality of cells generated by foaming the foaming agent,
• a ratio of the total area of the plurality of cells in a cross section of the reinforcement layer is 83% or more, and
• an elastic modulus of the matrix resin of the reinforcement layer is 1.4 GPa or more.