Name: protecting mortar during weather changes
Uploaded: 2024-09-12T16:16:29.000Z
Duration: 1 min 21 s
Channel: JoVE

Durante el clima frío, se utiliza cemento de endurecimiento rápido en la preparación del mortero. Se le agrega agua caliente, manteniendo la temperatura del mortero entre 40 grados a 120 grados Fahrenheit, hasta su colocación.
Para temperaturas inferiores a 32 grados Fahrenheit, las unidades de mampostería y los sacos de cemento se almacenan en una plataforma elevada, se cubren con láminas resistentes al agua y se calientan con calentadores.
La congelación de la arena se evita calentándola con una manta eléctrica o tubos de calor.
Además, se proporcionan cortavientos en el lugar de trabajo si la velocidad del viento es superior a 15 millas por hora.
Al final del trabajo, el muro de mampostería se cubre con mantas aislantes durante 24 horas para evitar la congelación.
Durante el clima cálido, las unidades de mampostería, la arena, las bolsas de cemento y el equipo de mortero están protegidos de la luz solar directa.
Para la mampostería en climas cálidos, se practica el lavado del equipo de mortero con agua, la adición de agua fría a la mezcla de mortero y la prehumectación de las unidades de mampostería antes de colocarlas.
Al final del trabajo, se aplica un spray de niebla sobre la mampostería y se cubre con membranas resistentes a la intemperie para protegerla del sol.

mampostería en condiciones climáticas frías y cálidas

En climas fríos, la construcción de mampostería requiere precauciones específicas para garantizar que el mortero no se congele antes de curarse, ya que esto puede debilitar significativamente su resistencia e impermeabilidad. La temperatura del mortero debe mantenerse entre 15,56 °C y 26,67 °C para asegurar una hidratación y un curado adecuados. Por debajo de los 4,44 °C, el agua del mortero debe calentarse, pero no debe superar los 48,89 °C, ya que las altas temperaturas pueden reducir la resistencia a la compresión y la adherencia del mortero.

Otras prácticas clave incluyen mantener los bloques de mampostería y la arena secas y protegidas de las temperaturas de congelación, usar arena calentada para mantener el mortero a una temperatura óptima y usar cemento tipo III para un curado más rápido. El mortero debe mezclarse en lotes pequeños para evitar que se enfríe, y las estaciones de trabajo de los albañiles deben protegerse del viento y calentarse si es necesario. La mampostería recién colocada necesita protección contra la congelación durante al menos un día, y las superficies deben cubrirse para protegerlas de la lluvia y la nieve.

En climas cálidos, el desafío es evitar que el mortero se seque demasiado rápido. Es posible que sea necesario humedecer los bloques de mampostería antes de usarlos para evitar la absorción excesiva de agua del mortero. Mantener los bloques de mampostería, los ingredientes del mortero y las estaciones de trabajo a la sombra ayuda a solucionar este problema. A menudo, la mampostería se trata con un aerosol de niebla y luego se cubre con membranas resistentes a la intemperie para protegerla de la luz solar al final del día.

Mampostería en condiciones climáticas frías y cálidas

Durante el clima frío, se utiliza cemento de endurecimiento rápido en la preparación del mortero. Se le añade agua caliente, manteniendo la temperatura del mortero entre 40 grados ...

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

Education

Educación

JoVE Core

Civil Engineering

Ingeniería Civil

Unit 1

Unidad 1

Masonry

Albañilería

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

Masonry in Cold and Hot Weather Conditions

protecting mortar during weather changes

Masonry work changes in cold and hot weather because mortar must stay at the right temperature and moisture level. If mortar freezes before it cures, its strength and watertightness can drop. For proper hydration and curing, mortar should stay between 60°F and 80°F.

When the weather is below 40°F, the water used for mortar must be heated. The water should not exceed 120°F, because very hot water can reduce compressive strength and bond strength. Masonry units and sand should also stay dry and protected from freezing. Heated sand can help keep the mortar near the best temperature.

Cold-weather work also calls for Type III cement, which cures faster. Masons should mix mortar in small batches so it does not cool too much before use. Workstations should be shielded from wind and heated when needed. Newly laid masonry must be protected from freezing for at least one day. Surfaces should also be covered to block rain and snow.

Hot weather creates the opposite problem, because mortar can dry too fast. Masonry units may need to be dampened before use so they do not pull too much water from the mortar. Keeping the units, mortar ingredients, and work area in the shade also helps. At the end of the day, masonry is often given a fog spray and then covered with weather-resistant membranes to protect it from sunlight.

Protecting Mortar During Weather Changes

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masonry in cold and hot weather conditions

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key terms and concepts

Learn how cold and hot weather affect masonry mortar, from heating materials and using Type III cement to shading, dampening, and fog spraying.

Protecting Mortar During Weather Changes | 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

Protecting Mortar During Weather Changes

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