ブックタイトル未来につなぐ人類の技17　煉瓦造建造物の保存と修復

概要

未来につなぐ人類の技17　煉瓦造建造物の保存と修復

ほどよい（infinite）と考えられ、面として強固にするために、木造の床組は鉄筋コンクリート造に置き換えられてきました。しかし今では、経験を踏まえてこの方法に「注意しなさい」と忠告できます。剛性を高めるということは、構造応答を高めることを意味し、そのために、（RCに置き換えるのではなく）例えば既存の床板の上に、もう1枚床板を敷いて緊結するという手法が考えられます。これは補強の効果を確認しているところです。また過去の例ですが、筋交いも使用しています。板材あるいは合板を用いた補強に代わる方法となります。木造小屋組の補強（スライド63-64）伝統的な木造建造物で、局所荷重（local bearing）を受けるために部分ごとの補強をしている事例です。Prof. Eng. Claudio ModenaProf. Eng. Claudio ModenaInterventions - APPLICATIONSSM IngegneriaInterventions - APPLICATIONSSM IngegneriaInterventions to reduce excessive floor deformabilityInterventions to reduce excessive floor deformabilityInterventions aimed at the in-plane stiffening of existing floors must be carefullyevaluated since the horizontal seismic action is transferred to the different masonrywalls in function of the floor plane action, depending on its stiffness.Ca’Duodo, Padova, XV c.In plane and flexural floors stiffening with‘dry’techniques is obtained by providing, atthe extrados of the existing floor, a further layer composed by wooden planks, withorthogonal direction respect the existing.AxonometricviewThe use of metallicbelts or FRP strips,disposed in a crossedpattern and fixed at theextrados of the woodenfloor or the use ofmetallic tie-beamsbracings, may improvethe stiffening effect.A. Borriスライド59スライド62Prof. Eng. Claudio ModenaProf. Eng. Claudio ModenaInterventions - RESEARCHInterventions to reduce excessive floor deformability? Different strenghetning systems(plankings, diagonals, nets, ..) and materials(wood, earth, FRP, Natural fibres) applied atthe extrados, for a total of 35 laboratorytests? High performance obtained for woodenplanking (45°, single or double) both forstrength and deformation capacity? The shear stiffness of the joist ceiling isprincipally influenced by the plankingthickness? The shear capacity of the floors is linearlyrelated with the strength of the fasteners? Proper double planking provides stiffnesscapable to redistribute horizontal loads tobearing walls, comparable to the effect ofmore modern floorsSM IngegneriaInterventions - APPLICATIONSInterventions on the roof structuresDucale Palace, UrbinoSM Ingegneriaスライド60スライド63Prof. Eng. Claudio ModenaProf. Eng. Claudio ModenaInterventions - RESEARCHInterventions to reduce excessive floor deformability? Different strenghetning systems(plankings, diagonals, nets, ..) and materials(wood, earth, FRP, Natural fibres) applied atthe extrados, for a total of 35 laboratorytests? High performance obtained for woodenplanking (45°, single or double) both forstrength and deformation capacity? The shear stiffness of the joist ceiling isprincipally influenced by the plankingthickness? The shear capacity of the floors is linearlyrelated with the strength of the fasteners? Proper double planking provides stiffnesscapable to redistribute horizontal loads tobearing walls, comparable to the effect ofmore modern floorsSM IngegneriaInterventions - APPLICATIONSInterventions on the roof structuresArsenale, Venice, XII c.36363626262727121227 28122831283117311728172828313127,53127,5627,526 63229626 3226 3229292929 2927,52527,52522 3422 3422 347788SM Ingegneriaスライド61スライド6429 292959