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

組積造壁体の補強（スライド65-69）最後に、どのようにして組積造壁体の質を高め、耐力を向上させるかという課題に挑んだ事例を紹介します。石を使った組積造建造物の内部に多くある間隙を充填し補強することで、壁体の力学的挙動（mechanical behavior）を改善し、性能を高めています。また、２つの層を横方向に緊結することで、力学的応答（mechanical response）も飛躍的に向上します。伝統的な方法ではありますが、どこでも使われていたわけではありません。裕福でなかった家ではこの方法は用いられなかったので、緊結の対策が必要となっています。（スライド70-71）これらの補強方法について、静的、動的な試験を行い効果を確認しています。どの手法が組積造に対して効果があるか、いくつもの簡単な試験を実物の組積造を用いて行っています。現在、地震の被災地であるイタリア中部では、このような試験を用いて、同Prof. Eng. Claudio ModenaProf. Eng. Claudio ModenaInterventions to strengthen the masonry wallsInterventions - RESEARCHSM IngegneriaInsertion of tiesInterventions - APPLICATIONSSM IngegneriaInterventions aimed at increasing the masonry strength may be used to re-establish the originalmechanical properties lost because of material decay or to upgrade the masonry performance.Techniques used must employ materials with mechanical and chemical-physical properties similar to theoriginal materials.Interventions should be uniformly distributed (both strength and stiffness).With opportune cautiousness, suggested techniques are the“scuci-cuci”, noncement-based mortar grouting, mortar repointing, insertion of“diatoni”(masonryunits disposed in a orthogonal direction respect the wall’s plane) or small size tiebeams across the wall, with connective function between the wall’s leaves.Mortar repointingInjections technique:example of suitableexecution and ofproblems related touncorrected execution(e.g. lack of uniformity)スライド65スライド68Prof. Eng. Claudio ModenaProf. Eng. Claudio ModenaInterventions - RESEARCHSM IngegneriaInterventions - RESEARCHSM IngegneriaInterventions to strengthen the masonry wallsInterventions to strengthen the masonry wallsApplication of transversal elements and ties to walls research: stone masonry walldiatonoEffect of six injection grouts, use to strengthen irregular stone masonry walls, damaged by April 6 th 2009earthquake? Diagonal compression test;? Characterization of grout-original mortar interface.? Improvement in the strength of the wall? Reduction of the dilatancy of the walls1.40Muro 11T401.20? (MPa)20311.0000.800.60-20-7 -7-160.400.20? ( o / oo)0.00-15.0-10.0-5.00.05.010.015.0vertAorizzRvertBorizzAorizzBorizzL-40-58 -40-604X 6I1 1I2 8I2 2T 9T%original wall injection transversal tieスライド66スライド69Prof. Eng. Claudio ModenaProf. Eng. Claudio ModenaInterventions - RESEARCHSM IngegneriaInterventions - RESEARCHSM IngegneriaInterventions to strengthen the masonry wallsShaking table tests on Out-of-Plane behaviour of single structural elementsInterventions to strengthen the masonry walls? Failure mechanisms;? Variation of dynamic characteristics (frequencies, mode shapes);Dynamic behaviour whole structures Building ModelsFloor Dimensions:2.40m x 2.8mMasonry deepness: 0.33m(12cm external layers 9cm internal filler)Height: 3.60mDouble planking wooden floorsRegular openingsAdditional masses (500kg per floor)UnstrengthenedconditionStrengthenedusing tiesStrengthenedusing injectionStrengthened using tiesand injection0.25g 0.45g 0.60g 0.75gPenna et al. 2009Montenegro earthquake (14/4/1979) waschosen and the signal was elaboratedconsidering the scale factor of 2:3;スライド67スライド7060第5章建築遺産の修復と補強に関する基準と技術：研究と応用