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

Considere um grande shopping center com uma estrutura de construção geometricamente complexa. Este complexo é subdividido em unidades pequenas, geometricamente compactas e independentes, usando juntas de separação de edifícios.
Essas juntas são classificadas como juntas de mudança de volume, juntas de assentamento e juntas de separação sísmica.
As juntas de mudança de volume são colocadas em descontinuidades horizontais ou verticais no edifício para aliviar os efeitos da expansão e contração das unidades do edifício.
Geralmente, essas articulações estão localizadas em intervalos de 150 a 200 pés.
A torre e a ala baixa adjacente do edifício são separadas por meio de juntas de assentamento projetadas para evitar problemas devido às diferentes taxas de assentamentos previstos para os diferentes tipos de fundação fornecidos.
As juntas de separação sísmica são fornecidas entre os segmentos do edifício para permitir que as unidades individuais se movam de forma independente durante um terremoto, evitando danos umas às outras.
Por fim, as unidades individuais existentes em ambos os lados do plano da junta de separação do edifício podem ter suas fundações, colunas e lajes distintas, tornando-as estruturas independentes que podem se mover como uma unidade em resposta às forças que atuam sobre elas.

tipos de juntas de separação de edifícios

As juntas de separação de edifícios dividem estruturas de edifícios grandes ou complexas em unidades menores e discretas que podem se mover independentemente. Essas juntas são categorizadas em três tipos: juntas de mudança de volume, juntas de assentamento e juntas de separação sísmica.

As juntas de mudança de volume abordam os efeitos da expansão e contração devido a variações de temperatura e umidade. Elas são colocadas estrategicamente em descontinuidades na massa de um edifício onde a fissuração é mais provável e são espaçadas cerca de 45,72 a 60,96 metros de distância em estruturas alongadas, com espaçamento adaptado às propriedades do material e à extensão das mudanças dimensionais esperadas.

As juntas de assentamento são usadas para evitar o desgaste estrutural que pode ocorrer devido às taxas de assentamento diferenciais em diferentes partes de um edifício. Essa situação pode surgir em estruturas com vários tipos de fundação ou aquelas construídas em diferentes condições de solo.

As juntas de separação sísmica são projetadas especificamente para edifícios em áreas propensas a terremotos. Essas juntas dividem o edifício em segmentos menores para garantir que cada parte possa se mover independentemente durante eventos sísmicos, minimizando o risco de danos.

No geral, juntas de separação de edifícios são implementadas construindo estruturas independentes em ambos os lados da junta, às vezes com fundações e elementos estruturais completamente separados, garantindo movimento gerenciável em resposta a várias forças.

Tipos de juntas de separação de edifícios

Considere um grande shopping center com uma estrutura de construção geometricamente complexa. Este complexo é subdividido em pequenos, geometricamente compactos, independentes ...

Education

JoVE Core

Civil Engineering

Engenharia Civil

Unit 1

Unidade 1

Masonry

Alvenaria

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

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

building-joints-for-movement-and-stability

composite masonry walls

Bonding and Materials in Composite Masonry

Composite masonry walls use two or more wythes, or vertical layers, of masonry to form one unified wall. The wythes may use the same material or different masonry materials. They are joined to work together as a single structure. These wythes can be bonded in several ways. Builders may use mortar-filled collar joints, grouted spaces, or rigid metal ties with reinforcement. Masonry header units can also connect the layers, but this method is rare. Metal ties are often preferred because they...

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Masonry Cavity Walls and Moisture Control

Masonry cavity walls use two wythes, or layers, with a hollow space between them. The outer and inner wythes are linked only by corrosion-resistant metal ties. This design helps manage water and improve wall performance. When rainwater passes through the outer wythe, it moves down through the cavity. Flashing catches the water and directs it toward weep holes, where it can leave the wall. The inner wythe often has damp-proofing on the cavity side. This layer also works as an air barrier. The...

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Masonry Curtain Walls and Support Systems

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How Masonry Walls Gain Extra Strength

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cavity drainage and flashings in masonry walls

cavity-drainage-and-flashings-in-masonry-walls

Moisture Control in Masonry Cavity Walls

Masonry cavity walls use a gap between two wythes, or wall layers, to help control moisture. The cavity is usually at least 2 inches wide, and it may contain insulation. Even with insulation, a clear space of at least 1 inch is kept so water can drain away. Some walls also use a continuous drainage mat to reduce the needed space while still moving moisture out. Weep holes are another key part of cavity drainage. These openings sit at the base of the cavity and let collected water escape. They...

thermal insulation in masonry walls

Masonry Wall Insulation Options

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expansion and contraction in masonry walls

expansion-and-contraction-in-masonry-walls

Masonry Wall Joints for Temperature and Moisture

Masonry walls change size slightly as temperature and moisture change. Builders account for this movement so the wall does not crack or shift out of place. Thermal movement is usually easy to measure and plan for. Moisture movement is harder to predict. New clay masonry units often absorb water and expand over time in normal outdoor conditions. New concrete masonry units behave differently. They usually shrink as they lose extra moisture gained during production. These opposite changes make...

movement joints in buildings

How Buildings Handle Structural Movement

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types of building separation joints

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,...

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Repairing Damaged Mortar Joints in Masonry

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masonry-in-cold-and-hot-weather-conditions

Protecting Mortar During Weather Changes

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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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