Installation of reinforced concrete structures

Modern construction relies heavily on reinforced concrete structures, which provide strength and durability for a variety of applications. These constructions, which range in size from massive skyscrapers to robust bridges, serve as the framework for many of the everyday structures and infrastructures that we depend on.

Reinforced concrete installation requires a team of highly qualified workers, exact engineers, and premium materials. To build sturdy, dependable structures, the procedure entails clearing the ground, putting together the framework, and pouring the concrete. To guarantee that the finished product satisfies safety regulations and design specifications, each stage necessitates meticulous planning and execution.

It can be very helpful to understand the fundamentals of installing reinforced concrete, whether you’re a novice DIYer or a seasoned contractor. It not only makes it easier to understand how complicated construction projects can be, but it also gives you the confidence to take on smaller jobs. This post will examine the essential phases of erecting reinforced concrete structures and provide helpful advice and insights to help you along the way.

What types of reinforced concrete structures are there?

There are three categories of products: prefabricated, monolithic, and prefabricated-monolithic. The first are factory samples that are joined together or welded to a frame before being concreted. The latter should be directed towards structures (foundation plates, pools, self-winging frames, etc.) whose frames can support heavier loads.

The latter logically integrate the diverse components of the initial and subsequent kinds. Conventional and pre-tense reinforcement, which increases resistance to loads acting on bending, is installed in factory structures. All that is present in monolithic products is a standard reinforcement cage.

Regulatory documents

SNiP 3.03.01-87, which provides guidelines for all phases of the installation of reinforced concrete structures, materials, and technologies. General requirements for the formation of products from reinforcement and embedded parts for their welding in reinforced concrete structures are outlined in GOST 10922-90. GOST 14098-91 standardizes structural design types and the geometric parameters of joints when welding reinforcement and embedded parts. The project for the production of works at construction sites (PPR) includes the requirements of the listed documents.

One of the most important aspects of contemporary construction is the installation of reinforced concrete structures, which give infrastructure and buildings the necessary strength and longevity. This post will walk you through the processes of putting together, finishing, and fastening reinforced concrete, guaranteeing a sturdy framework and foundation. Comprehending these techniques is essential for building sturdy and long-lasting structures, regardless of your level of experience or interest in do-it-yourself projects.

How the installation of structures occurs?

Precast concrete and reinforced concrete structures are installed in the following ways:

• intermediate storage and movement of products;
• installation of reinforced concrete products from precast elements;
• work with concrete mixtures;
• reinforcement in monolithic structures;
• pouring and curing of concrete until strength is gained;
• concrete processing.

Storage and movement

Products are positioned on the construction site while keeping the installation order in mind. Products are stacked in group cassettes or on spacers that are roughly 3 cm high and arranged strictly one underneath the other (individual stacking is allowed for a given type). The crane’s installation zone, which is its working radius without affecting the reach of its boom, is where the frame components are positioned. Only when moving floor slabs is it permissible to alter the boom reach. Only lifting equipment is used to move structural components.

As per the drawings, slings are fastened to the installation reinforcement. For loads up to 50 kg, manual carrying is permitted up to a 30-meter distance (dragging is not permitted). It is acceptable to arrange similar components (beams, columns, etc.) prior to assembly. to examine the condition of the issues with reinforcement. Such structural problems are shielded from harm; it is inappropriate to attach the slings to them.

Static is used to raise and lower the goods at a height of 300 mm above the end or installation point. When the products are installed in the building structure, their spatial position (panels, columns, staircases, etc.) must match the design position. They are used with one or two guy lines attached to them to help with orientation in the air. Metizes are arranged in a specific room in a sorted manner on the construction site.

Concrete works

Concrete composition components are dosed according to weight. The amount of water in the solution serves as a guide for the amount of modifying additives that alter the fluidity, hydrophobicity, resistance to frost, and other characteristics of concrete. By evaluating samples for strength and mobility, the component proportions are established in relation to all batches (brands) of cement and fillers. It is forbidden to add water to the mixed mixture in order to make the concrete more workable. Table 1 displays the specifications set forth by SNiP 3.03.01-87 for the creation of solutions.

Styled areas, including their seams and surfaces, are cleared of debris, oil and fat stains, and cement dust film, as well as seasonal sedimentary moisture. They are then pressure-washed and allowed to dry. The filler grain fractions should not exceed 3/4 of the minimum distance between the reinforcing bars and should not be larger than 1/3 of the joint cross-section at its narrowest point. Layers of concrete are poured in. To use a vibratory rammer, submerge the instrument between 50 and 100 mm below the surface.

It is unacceptable to support embedded parts, formwork, and reinforcement with it. The equipment’s step of movement on the surface is 1.5 times its action radius. Models of surface action are rearranged so that compaction areas overlap by 100 mm. Once the previous layer of mortar has strengthened to 1.5 MPa, subsequent layers are poured.

Concrete processing

Once the concrete has strengthened, a 20–30 mm high cement screed coated in waterproofing compound is placed on top of it. Technology-induced holes and openings, or anti-deformation joints (a set of strength indicators of 50% and above), are formed in the reinforced concrete frame. Using diamond cutting tools with forced heat removal from the working area is preferred (vibration loads excluded).

Reinforcement

Installing factory-made flat reinforcing meshes with longitudinal and transverse components in the formwork is how structures are strengthened. This kind of reinforcement prevents transverse rods from deforming and groups long rods. Volumetric joining of structural reinforcement layers within the formwork and functional reinforcement of various products is accomplished by means of screw couplings, crimping sleeves, knitting wire, welding, and other techniques. Prior to pouring, the form is cleaned of scale and debris, and the quality of the metal installation is inspected.

A 20–30 mm-high protective layer of concrete must surround the reinforcing structure on all sides. Compaction is achieved by vibratory rammer and bayonet tamping in addition to the solution being poured. The lower columns of the building must have a minimum of 2.01% reinforcement (calculated by adding the cross-sectional areas of the reinforcing metal to the total cross-sectional area of the structure), while the upper columns must have a minimum of 0.79%. No more than 0.1% of the concrete structure can be filled with metal.

Pouring and maintenance

During the warm season, concrete is covered with polyethylene film, shielded from direct sunlight heat, and protected from uneven drying with moisture-absorbing materials. Water is poured into the concrete 10–14 hours after it is poured, and it is left wet for 7–14 days. The product is still being irrigated after the side formwork is removed, which takes 10 to 14 days. With the right tools, the pouring can be heated during cold weather. After 70% of the grade strength is reached (28 days for conventional compositions), installation work on cast components starts.

Features of installing prefabricated products

When installing reinforced concrete structures, spans are used to monitor how the structure frames come together to form a sturdy structure. Assembling is done in accordance with process maps and project specifications. After the frame is fastened and the monolithic reinforced concrete structures (inserts) have reached 70% strength, a new layer of structural elements is added. Inspections are conducted on structural units to look for flaws like chips, cavities, exposed reinforcing, etc. The overall measurements, holes, reinforcement outlets, and embedded parts are also examined.

The columns are put into the cups in the design position right away using a hard leveling mortar; placing them on metal is not acceptable. The products’ height marks indicate how thick it is. Only after being final fixed in the cup with wedge-shaped inserts (braces, conductors), are the slings taken out of the columns. A set of installation tools ensures that welded columns, wall panels, etc. are securely fixed; they are not loaded until the monolithic concrete has reached grade strength. If required, jacks are used to raise the reinforced concrete column to its vertical position (within tolerances).

The reinforcement is shielded from corrosion prior to monolithing. Vibration compacts the mortar in the cup sockets. Concretes of higher grades (quick-hardening, expanding from M400 and higher) than those used in the project are used to form loaded joints. Once the monolithic structure reaches the necessary strength, the inserts are removed. The PPR outlines the types of reinforcement to be joined, how all joints will be sealed (caulked), and whether mortar or monolithic construction will be used.

Welding is used to secure floor slabs, beams, columns, and embedded plates. Floor slabs are installed with a maximum 2 cm of mortar, and the general plane of the slabs is inspected from the side facing the ceiling. Four points are welded at the first slab, and three nodes at the subsequent slabs.

Without mortar, beams, rafter beams, and intercolumn slabs are installed. In horizontal joints, ventilation blocks are hermetically sealed with mortar. It is forbidden to strike welded joints at the following temperatures: minus 25 degrees for steel with a yield limit of up to 390 MPa, and zero degrees for steel with a yield limit of 390 MPa or higher.

Modern construction relies heavily on reinforced concrete structures because they offer the infrastructure and buildings the strength and durability they need. To guarantee longevity and safety, the installation of these structures calls for careful planning and exact execution.

Every step of the process, from clearing the area and erecting the formwork to pouring and curing the concrete, requires close attention to detail. Reinforced concrete is a dependable material for a variety of construction projects because it can withstand enormous loads and challenging environmental conditions when installed correctly.

The success of your project can be considerably impacted by your understanding of the methods and best practices for installing reinforced concrete structures. You can create a strong, long-lasting structure that endures by adhering to industry standards and guidelines.

Gaining expertise in the installation of reinforced concrete structures can open up a world of opportunities for anyone, professional builder or do-it-yourself enthusiast. You can build impressive, long-lasting, and safe structures that fulfill your needs and surpass your expectations if you have the necessary information and resources.

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