All Of The Following Are Common Types Of Temporary Supports, EXCEPT: A. Sandbags B. Cradles C. Pipe Stands D. Bolted Sleeves

by ADMIN 132 views

Temporary supports are crucial in various engineering applications, providing stability and load-bearing capacity during construction, maintenance, or repair work. These supports ensure safety and prevent structural failure while allowing workers to perform their tasks effectively. Understanding the different types of temporary supports and their specific applications is essential for engineers and construction professionals. This article will delve into common types of temporary supports, discuss their uses, and identify the exception among the given options.

Understanding Temporary Supports

Temporary supports, as the name suggests, are structures used to provide interim support to a building, bridge, or other structure. These supports are necessary when a structural element is removed or altered, or when additional loads are applied during construction or maintenance. The primary goal of temporary supports is to maintain the structural integrity of the system and ensure the safety of workers and the public. Choosing the correct type of temporary support depends on factors such as the load requirements, the geometry of the structure, and the duration of the support needed. Proper installation and regular inspection of temporary supports are critical to prevent accidents and ensure their effectiveness.

Common Types of Temporary Supports

Several types of temporary supports are commonly used in engineering and construction. These supports vary in design, load-bearing capacity, and application. Some of the most common types include:

  1. Sandbags: Sandbags are a versatile and cost-effective solution for providing temporary support and stabilization. They are typically made of burlap or polypropylene and filled with sand or other granular material. Sandbags are easy to handle and can be stacked to create walls or supports of various shapes and sizes. Their primary advantage is their ability to conform to irregular surfaces, making them suitable for a wide range of applications. For example, sandbags are often used to stabilize trenches, support excavation walls, and provide ballast for temporary structures. They are also commonly used in flood control and erosion prevention.

  2. Cradles: Cradles are temporary supports designed to hold and support cylindrical or curved objects, such as pipes, tanks, or bridge girders. These supports typically consist of a curved frame or structure that conforms to the shape of the object being supported. Cradles distribute the load evenly and prevent damage to the supported object. They are commonly used in bridge construction, pipeline installation, and maintenance of storage tanks. The design of a cradle must consider the weight and dimensions of the object being supported, as well as the environmental conditions and potential loads. Proper fabrication and installation of cradles are crucial to ensure their structural integrity and stability.

  3. Pipe Stands: Pipe stands are temporary supports specifically designed to support pipes during installation, maintenance, or repair. These stands typically consist of a vertical post with an adjustable head that can be positioned to the desired height. Pipe stands are available in various sizes and load capacities to accommodate different pipe diameters and weights. They are essential for maintaining the alignment and stability of pipes during welding, cutting, or threading operations. The use of pipe stands helps to prevent sagging or bending of pipes, which can lead to leaks or structural failure. Proper spacing and secure attachment of pipe stands are essential for ensuring the safety and stability of the piping system.

  4. Bolted Sleeves: Bolted sleeves are commonly used in structural engineering for splicing or reinforcing structural members, particularly steel beams and columns. While they provide structural support, they are generally considered a permanent connection method rather than a temporary support. Bolted sleeves consist of two or more steel plates that are bolted together around the member being spliced or reinforced. The bolts transfer the load between the plates and the member, creating a strong and reliable connection. Bolted sleeves are often used in bridge construction, building renovation, and seismic retrofitting. The design of bolted sleeves must consider the load requirements, the dimensions of the member being spliced or reinforced, and the material properties of the steel plates and bolts. Proper installation and tightening of the bolts are critical to ensure the effectiveness of the connection.

Identifying the Uncommon Type

Given the options:

a. Sandbags b. Cradles c. Pipe stands d. Bolted sleeves

Based on the descriptions above, sandbags, cradles, and pipe stands are all commonly used as temporary supports in various engineering and construction applications. However, bolted sleeves are primarily used as a permanent connection method for splicing or reinforcing structural members. While they provide structural support, their primary purpose is to create a lasting connection rather than a temporary support during construction or maintenance.

In-Depth Look at Each Option

To further clarify the distinction, let's delve into each option in more detail:

  • Sandbags: Sandbags are indeed a classic example of temporary support. Their versatility and adaptability make them ideal for a wide range of applications. For instance, in excavation projects, sandbags can be used to create temporary retaining walls, preventing soil collapse and ensuring worker safety. They are also frequently employed in emergency situations, such as flood control, where they can quickly be deployed to create barriers against rising water levels. The ease of handling and the ability to conform to irregular shapes make sandbags a practical choice for situations requiring immediate and flexible support. In road construction, sandbags might be used to support temporary signage or to stabilize the ground before laying asphalt. The key feature of sandbags as temporary supports is their impermanence; they are easily removed once the need for support has passed.

  • Cradles: Cradles are specifically engineered to provide temporary support to cylindrical or curved structures. In bridge construction, for example, cradles are essential for supporting bridge girders during the lifting and placement process. These temporary supports ensure that the girders are held securely in place, preventing any movement or instability that could compromise the structure's integrity. In the maintenance of pipelines, cradles are used to support sections of pipe that are being repaired or replaced. The design of a cradle must take into account the specific dimensions and weight of the object being supported, as well as any potential environmental factors, such as wind or seismic activity. The adjustable nature of many cradles allows for precise positioning and alignment, making them an indispensable tool in many engineering projects. Again, the temporary nature of cradles is crucial; they are removed once the permanent supports are in place.

  • Pipe Stands: Pipe stands are indispensable in the installation and maintenance of piping systems. These temporary supports provide a stable base for pipes, preventing them from sagging or moving during construction or repair. In large-scale industrial projects, where extensive piping networks are common, pipe stands are essential for ensuring the proper alignment and stability of the system. They are also used in plumbing and HVAC installations, providing a secure means of supporting pipes while connections are made. Pipe stands come in various sizes and load capacities, allowing them to accommodate a wide range of pipe diameters and weights. The use of pipe stands not only enhances safety but also improves the efficiency of the work process, as workers can focus on making connections without having to manually support the pipes. As with the other temporary supports, pipe stands are removed once the piping system is fully supported by permanent fixtures.

  • Bolted Sleeves: Bolted sleeves, while providing structural support, are fundamentally different from the other options in that they are designed for permanent installations. These devices are used to reinforce or splice structural members, creating a lasting connection that is intended to remain in place for the life of the structure. In bridge construction, for example, bolted sleeves might be used to strengthen steel beams or columns, enhancing their load-bearing capacity. In building renovations, they can be used to reinforce existing structural elements, allowing for the addition of new floors or modifications to the building's layout. The installation of bolted sleeves involves bolting steel plates around the member being reinforced, creating a strong and reliable connection. The design and installation of bolted sleeves must adhere to strict engineering standards to ensure their effectiveness and durability. Unlike the other options, bolted sleeves are not removed after the construction or repair work is completed; they become an integral part of the structure. This permanence is the key distinction that sets bolted sleeves apart from temporary support systems.

Conclusion

In summary, sandbags, cradles, and pipe stands are all common types of temporary supports used in engineering and construction. These supports provide interim stability and load-bearing capacity during various phases of a project. However, bolted sleeves, while providing structural support, are primarily used as a permanent connection method. Therefore, the correct answer to the question is:

d. Bolted sleeves

Understanding the difference between temporary and permanent support systems is crucial for engineers and construction professionals to ensure the safety and integrity of structures. The appropriate selection and use of temporary supports are essential for successful project execution and the prevention of accidents or structural failures.