PROBLEM TO BE SOLVED: To provide reinforcement props and house structures using reinforcement props which have high flexibility, can be installed and removed simply when necessary, and can support a roof part of a pipe structure with large buckling strength.SOLUTION: An outer pipe 25 which is provided with a butterfly bolt 37 at its upper end 26a and a settling preventing plate 31 fixed to its lower end 26b so as to stand on the ground； an inner pipe 27 inserted from the upper end 26a of the outer pipe 25 and having a groove 47 which allows a butterfly bolt tip 45 to enter and, in the lower end 28b, inclines inward in the radial direction toward a lower end 28b in the direction along the axis so as to form a fillet section 49 which touches a butterfly bolt tip 45； a connecting member 29 having a support plate 59 fixed to the lower side of a ridge pipe 15 by both lower ends of U-shaped bolt 57 which sandwiches the ridge pipe 15 from above in inverted U-shaped direction to penetrate and fasten and provided in the lower surface of the support 59 with a drooping section 61 which is formed to taper toward downward from the ridge pipe 15 and is capable of being inserted into an upper end 28a of the inner pipe 27.SELECTED DRAWING: Figure 10【課題】汎用性が高く、必要な時に簡易に設置及び取り外しができ、しかも、パイプ構造の屋根部分を大きな座屈強度で支持できる補強用支柱及び補強用支柱を用いたハウス構造を提供する。【解決手段】上端２６ａに蝶ボルト３７を備え下端２６ｂに沈下防止板３１が固定されて地面に立設される外パイプ２５と、外パイプ２５の上端２６ａから挿入され、下端２８ｂには蝶ボルト先端４５が進入可能な溝４７が軸線に沿う方向で下端２８ｂに向かって半径方向内側に傾斜し、蝶ボルト先端４５の当たる溝底部４９が形成される内パイプ２７と、逆Ｕ字の向きで上から棟パイプ１５を挟んだＵ字ボルト５７の両下端が貫通して締結されることにより、棟パイプ１５の下側に固定される支持板５９を有し、支持板５９の下面には、棟パイプ１５より下方に向かって先細に形成され、内パイプ２７の上端２８ａに挿入可能な垂下部６１が設けられる連結部材２９と、を具備する。【選択図】 図１０
