Name: building joints for movement and stability
Uploaded: 2024-09-12T16:16:29.000Z
Duration: 1 min 23 s
Channel: JoVE

Prenons l’exemple d’un grand centre commercial avec une structure de bâtiment géométriquement complexe. Ce complexe est subdivisé en petites unités indépendantes géométriquement compactes à l’aide de joints de séparation de bâtiments.
Ces joints sont classés en joints de changement de volume, joints de tassement et joints de séparation sismique.
Les joints de changement de volume sont placés aux discontinuités horizontales ou verticales du bâtiment pour atténuer les effets de dilatation et de contraction des unités de bâtiment.
Généralement, ces joints sont situés à des intervalles de 150 à 200 pieds.
La tour et l’aile basse adjacente du bâtiment sont séparées à l’aide de joints de tassement conçus pour éviter les détresses dues aux différents taux de tassement prévus pour les différents types de fondations fournies.
Des joints de séparation sismiques sont prévus entre les segments du bâtiment pour permettre aux unités individuelles de se déplacer indépendamment lors d’un tremblement de terre, évitant ainsi de s’endommager les unes les autres.
Enfin, les unités individuelles existant de chaque côté du plan du joint de séparation du bâtiment peuvent avoir leurs fondations, colonnes et dalles distinctes, ce qui en fait des structures indépendantes qui peuvent se déplacer en tant qu’unité en réponse aux forces qui agissent sur elles.

types de joints de séparation de bâtiment

Les joints de séparation de bâtiment divisent les structures de grande taille ou complexes en unités plus petites et discrètes qui peuvent se déplacer indépendamment. Ces joints sont classés en trois types : joints de changement de volume, joints de tassement et joints de séparation sismique.

Les joints de changement de volume traitent des effets de dilatation et de contraction dus aux variations de température et d'humidité. Ils sont placés stratégiquement aux discontinuités de la masse d'un bâtiment où les fissures sont les plus probables et sont espacés d'environ 45,72 à 60,96 mètres dans les structures allongées, avec un espacement adapté aux propriétés du matériau et à l'ampleur des changements dimensionnels attendus.

Les joints de tassement sont utilisés pour éviter les dommages structurels qui peuvent survenir en raison de taux de tassement différentiels dans différentes parties d'un bâtiment. Cette situation peut se produire dans des structures avec différents types de fondations ou celles construites sur des conditions de sol différentes.

Les joints de séparation sismique sont spécifiquement conçus pour les bâtiments dans les zones sujettes aux tremblements de terre. Ces joints divisent le bâtiment en segments plus petits pour garantir que chaque partie peut se déplacer indépendamment pendant les événements sismiques, minimisant ainsi le risque de dommages.

Dans l’ensemble, les joints de séparation des bâtiments sont mis en œuvre en construisant des structures indépendantes de chaque côté du joint, parfois avec des fondations et des éléments structurels complètement séparés, garantissant un mouvement gérable en réponse à diverses forces.

Types de joints de séparation de bâtiment

Prenons l’exemple d’un grand centre commercial avec une structure de bâtiment géométriquement complexe. Ce complexe est subdivisé en petits ...

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Types of Building Separation Joints

building joints for movement and stability

Building separation joints help large or complex buildings move in a controlled way. They split a structure into smaller, separate units. This reduces stress when the building shifts under different forces.

The joints are grouped into three main types: volume-change joints, settlement joints, and seismic separation joints. Volume-change joints handle expansion and contraction caused by temperature changes and moisture changes. They are placed where the building mass has discontinuities, because cracking is more likely there. In long buildings, they are often spaced about 150 to 200 feet apart. The exact spacing depends on the material and on how much size change is expected.

Settlement joints prevent structural distress caused by different parts of a building settling at different rates. This can happen when one section uses a different foundation type or when parts of the building sit on different soil conditions. Seismic separation joints are used in earthquake-prone areas. They divide a building into smaller segments so each part can move on its own during shaking.

In practice, these joints are created by building independent structures on each side of the joint. In some cases, the sides have separate foundations and separate structural elements. This design helps the building respond to movement without major damage.

Building Joints for Movement and Stability

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key terms and concepts

Explore how building separation joints reduce cracking, settlement stress, and earthquake damage by letting large structures move in smaller independent sections.

Building Joints for Movement and Stability | JoVE K12

JoVE Core Civil Engineering provides a foundational exploration of essential construction materials in civil engineering, focusing on bricks, stones, steel, wood, and concrete through easy-to-understand animated videos. This collection covers the properties, manufacturing processes, and practical applications of these materials. Additionally, the accompanied science-in-action videos demonstrate the research experiments performed in laboratories.

civil engineering

Building Joints for Movement and Stability

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