For any construction project, building a solid and trustworthy foundation is essential. A monolithic reinforced concrete strip foundation is an excellent option for creating a strong foundation for your house or other structures. This kind of foundation is a popular choice for both builders and homeowners because it provides stability, longevity, and resistance to a variety of environmental factors.
There are several important steps involved in setting up a monolithic reinforced concrete strip foundation. For the foundation to function as intended at each step, meticulous planning, accuracy, and adherence to best practices are necessary. Whether you are a professional builder or a do-it-yourself enthusiast, knowing these steps will help you lay a solid foundation.
We will take you through each of the crucial steps involved in building a monolithic reinforced concrete strip foundation in this guide. We’ll go over every step in detail, from getting the site ready and erecting the formwork to pouring the concrete and giving it the proper cure. We’ll also provide insightful advice from knowledgeable experts to help you steer clear of typical pitfalls and extend the life of your foundation.
You can build a foundation that not only properly supports your structure but also endures over time by adhering to these guidelines. This guide will give you the knowledge and assurance to handle your foundation work with skill and precision, whether you’re building a new home, adding an addition, or starting a renovation project.
Stage | Description |
1. Site Preparation | Clear the area of vegetation and debris. Mark the foundation layout using stakes and string. |
2. Excavation | Excavate the soil to the required depth, ensuring a flat and stable base. |
3. Formwork Installation | Construct the formwork using wooden boards to shape the foundation. Ensure the formwork is level and secure. |
4. Reinforcement Placement | Install steel rebar within the formwork to reinforce the concrete. Tie the rebar together for stability. |
5. Concrete Pouring | Pour the concrete into the formwork, ensuring it is evenly distributed. Use a vibrator to remove air pockets. |
6. Curing | Allow the concrete to cure by keeping it moist. This process takes several days to achieve full strength. |
7. Formwork Removal | Carefully remove the formwork once the concrete has sufficiently hardened. |
8. Backfilling | Backfill the excavated area around the foundation with soil, compacting it to provide support. |
9. Waterproofing | Apply a waterproofing membrane to the exterior of the foundation to prevent water infiltration. |
10. Final Inspection | Inspect the completed foundation for any defects or issues. Make necessary repairs if needed. |
- Choosing the type of foundation
- Soil type
- Relief plot
- What is a monolithic strip foundation
- Depth
- Justified use of the strip
- Calculation of MZLF according to Sazhin
- Stages of work
- Digging by hand
- The width of the trench under the foundation
- TTK (standard process map)
- Formation
- Reinforcement
- Concreting
- Calculation of concrete for the foundation
- Recommendations for calculations
- Calculation of the strip foundation
- Video on the topic
- We installed the formwork. We tie the reinforcement
- We pour the slab foundation for the house
- The most STUPID solution in a strip foundation #construction #house #foundation
Choosing the type of foundation
It is worthwhile to carefully consider the type of foundation if you want the building to be sturdy and dependable, to last for a long time without needing frequent repairs. A well-arranged foundation is essential for the longevity and structural integrity of any building, regardless of the type of wall material used.
You should consider the following factors when making a decision that affect the foundation’s reliability:
- type of soil at the construction site;
- depth of groundwater;
- lower limit of seasonal soil freezing;
- elevation differences in the construction area;
- physical data of the future house: estimated weight and area.
What makes all of these data significant? Physics has the simple solution. Squeezing out heaving soils during rainy or freezing periods will result in a light building on a strong foundation. This will occur as a result of the soil’s increased volume, which will put more pressure on the building’s subsurface walls.
Soil type
It is crucial to realize that the kind of soil present at the construction site has a significant impact on the type of foundation. This factor influences the foundation’s depth in addition to the type of foundation. You must ascertain the type of soil in order to accurately compute the trench’s size. The types of soil, freezing depth, and types of soil are all described in the table.
The purpose of this conditional gradation is to assess the stability of building and structure foundations:
Soil type | Soil type | Freezing depth level |
Strongly heaving | Sandy loam | no more than 0.5 m |
Loams and clay | no more than 1 m | |
Moderately heaving | Sands | no more than 0.6 m |
Sandy loam | 1 m | |
Loams | no more than 1.5 m | |
Clay | up to 2 m | |
Weakly heaving | Sands | 1 m |
Sandy loam | 1.5 m | |
Loams | no more than 2.5 m | |
Clay | by 3 m | |
Conditionally non-heaving | Sands | over 1 m |
Sandy loam | more than 1.5 m | |
Loams | from 2 m | |
Clay | more than 3 m | |
Non-heaving | Any | Does not matter |
The information on soil moisture content and groundwater location at the moment when the soil starts to freeze is used to calculate the frost heaving coefficient.
Relief plot
In addition, the evenness and homogeneity of the relief should be taken into account when selecting a foundation. It is best to level plots that have a small slope. In the event that this isn’t feasible, the foundation depth is calculated starting at the lower level of the plot.
For instance: A typical project for a two-story cottage calls for the installation of a 1.8 m-high recessed strip foundation. There is a 0.7 m height difference at the construction site. Consequently, a trench is excavated that is 2.5 meters high and 1.8 meters deep at the bottom. Given the lower point in this instance, the trench’s bottom ought to have a distinct horizon line.
Setting up a strip foundation will be challenging if the site has significant height variations. Either a mixed foundation or a pile foundation is chosen in these circumstances.
Kindly take note! It is advisable to request calculated building weight data from the design organization. It is not advised to determine the foundation’s dimensions on your own without construction knowledge. You can use an online calculator to get an estimate of the amount.
What is a monolithic strip foundation
A monolithic reinforced concrete strip foundation is a solid structure formed by pouring concrete into formwork that has an internal reinforcing belt. This kind of foundation is put in place beneath every wall in the house, even the load-bearing ones. The cross-section of the foundation must always be the same.
It is fabricated in multiple configurations (vertical section):
- rectangle;
- trapezoid;
- T-shaped (shown in the photo).
Uniform distribution of all kinds of loads throughout the whole volume of the foundation is ensured by the closed and monolithic nature of the foundation strip. This characteristic explains why this kind of foundation is so strong and in such high demand in private construction.
Depth
It’s critical to ascertain the foundation’s appropriate depth of lowering in addition to its geometric shape. The depth of the foundation can vary depending on the mass of the building, the amount of soil freezing, the location of groundwater, and the type of soil.
- Shallow (up to 60 cm). This type of foundation is arranged for light buildings on heaving soils.
- Deep (below freezing level). Used as a foundation for buildings with underground spaces and heavy buildings.
The building’s weight and the kind of soil heaving determine the kind of strip foundation. The external loads acting on the strip foundation determine its depth.
Justified use of the strip
Although the strip foundation is practically perfect, there are situations when its construction is not warranted. Both in terms of materials and labor, this kind of foundation is highly costly. There are instances when choosing simpler bases—pile or columnar—is worthwhile.
However, there are instances in which the strip’s construction is wholly economically justified:
- For the construction of houses using heavy materials for walls and ceilings.
- On sites with multi-level soil stratification;
- When constructing buildings with underground spaces (basement, garage).
- In a situation where the construction of curved walls is required.
- If the groundwater level at the construction site is close to the surface.
When building a foundation of this kind, the integrity of the contour tape serves as the primary guideline. The foundation thread needs to remain intact whether the foundation is poured or constructed of blocks.
The following guidelines should be considered:
- the force of vertical pressure on the foundation, exerted by the mass of the building and variable load, must exceed the pressure exerted by the heaving forces on the foundation walls;
- on any type of soil, the depth of the foundation is arranged below the level of soil freezing;
- on heaving soils, under a monolithic foundation it is necessary to construct a sand (crushed stone) cushion;
- pouring is carried out only with the calculated grade of concrete specified in the design documentation;
- the number of reinforcing belts and the diameter of the reinforcing rod specified in the project cannot be changed.
The closed circuit of the monolithic foundation will guarantee uniform distribution of the power of vertical and horizontal pressure, subject to all construction standards and the calculated parameters specified in the project. This characteristic accounts for the strip base design’s appeal.
Calculation of MZLF according to Sazhin
Stages of work
Every event starts with planning. In this instance, the building site is cleared, and the required supplies are delivered. It is important to note that the prepared site should have a substantially larger area than the foundation that is being installed.
- Firstly, the trench itself must be wider than the foundation.
- Secondly, you will have to somehow move around the construction site and dump the selected soil somewhere. At the same time, it’s not worth dumping it, because in the end you’ll have to backfill it.
Markings are made after the area is prepped. Ropes and pegs are used in the process. The future foundation’s angles are meticulously confirmed.
Digging by hand
Finding the perimeter’s lowest point is essential when delineating the space for a strip foundation. This is accomplished very easily by using a water level.
It is necessary to dig a drainage well at the site’s lowest point. Additionally, drainage outlets need to be installed at the base of the foundation’s perimeter.
Following the marking installation, it is advised to do the following tasks before beginning any trench digging:
- Remove the turf along the inner perimeter of the foundation;
- Transfer the fertile layer of soil to the garden;
- Determine a place for dumping soil from the trench.
Up to 1.5 meters are left between the earth from the trench and the edge. They start by excavating the exterior walls before going on to the dividers. Sand is poured, water is spilled, and then the bottom is compacted if needed.
- Do not dig a trench for the foundation of an extension, removing soil from the main building.
- When digging a trench, do not forget to add to the width of the foundation the calculated diameter of the drainage pipe.
- In bulk soils, it is better to dig a trapezoidal trench. At the same time, the calculation value of the width will be the bottom of the trench.
The width of the trench under the foundation
The foundation is wider than the walls, and the trench is wider than the foundation, so we gather the nesting doll. The base, formwork, and an additional 40 cm (20 outside and 20 inside the building) are used to determine the trench’s size.
- As a rule, the size of the trench for the foundation of a private house is 70 – 80 cm. With such sizes, it is comfortable to dig and move inside the trench.
- You can dig a trench manually, or using construction equipment. If you rumble with your hands, then you should remove the lower layer as horizontally evenly, without violating the soil density.
- The crumbling soil should not be trampled, it must be pulled out of the trench. This is important because even a compacted land is greatly inferior to the natural density of the soil.
- In case of using machinery, upon completion of the work the bottom of the pit is leveled with sand or crushed stone, and carefully compacted with a mechanical vibrator.
Now that everything is ready, you can move straight on to the foundation device.
TTK (standard process map)
Technical and organizational document that defines materials and solution compositions and explains the technologies used in all processes. Typically, design documentation serves as the foundation for TTK development.
The process map makes the following specific:
- work production technologies;
- compositions of production operations,
- quality requirements;
- estimated labor intensity of work;
- production and material resources.
Based on and considering the following data, a process map for concreting a strip foundation is created:
- Indicators for a specific strip monolithic reinforced concrete foundation: drawing, plan, units in the context;
- building codes and regulations;
- norms and prices for construction and assembly work;
- production standards for material consumption;
- local approved coefficients.
Step-by-step instructions for building the facility will be included in the TTK: It is specified what kind of concrete is required for the shallow reinforced concrete strip foundation, whether a concrete pad is required underneath the foundation, and what kind of reinforcement should be used.
Formation
Formwork is installed in order to form a monolithic strip foundation. Protective structure installation is a straightforward procedure, but it does call for careful attention to detail and exact adherence to technology. The future subterranean wall’s dimensions are determined by the formwork.
One major benefit of having a monolithic foundation is that the structure is formed upon the fact of construction. Ultimately, this implies that there are no restrictions on the dimensions or design of the future home’s foundation.
You can construct a base for a bay window or decide on the necessary length for the base side. Formwork can be installed in a variety of ways without the need for construction machinery. Installing something like this yourself can save a lot of money on the project estimate.
Two varieties of formwork exist:
Type | Characteristic | Requirements |
Removable | In private construction, improvised means or inexpensive building material that can be used in further construction are used as removable panels: building boards, moisture-resistant plywood. | Panels should be lightweight and easy to attach and remove. |
Non-removable | Gives shape, limits concrete spreading, performs the function of hydro- and thermal insulation of the foundation walls. | Particularly high requirements are imposed on the service life of the panel material. |
Adherence to concreting technologies and properly positioned formwork ensure a sturdy foundation.
It is crucial that you:
- Control the vertical installation of the panels.
- The height of the formwork should extend 30 cm above the general ground level.
- When installing the formwork structure, do not forget to leave openings for utility lines.
- The material used for the formwork panels should be treated with waterproofing, covered with a film or thoroughly moistened before pouring the solution.
Kindly take note! Sometimes formwork panels are left out in an attempt to save costs. In this case, before pouring concrete, a trench with uniformly vertical walls is dug and a film is applied. What are the possible outcomes of this? The film will tear during reinforcement installation, causing moisture from the concrete to evaporate earlier than necessary. We’ll end up with an uneven foundation and extremely brittle concrete as a result.
Reinforcement
Concurrent with the formwork installation, the strip foundation’s concrete is reinforced through the assembly of reinforcing belts. The structures are fixed in place after being mounted on top and lowered into the trench in sections. The project specifies the thickness of the rod, the grade of metal, and the quantity of reinforcing threads.
Construction wire can be used to tie the rod or it can be welded. While rods marked A400 are tied rather than welded, reinforcement marked A500C is meant to be fastened by welding.
Corner joints created by welding or tying are not acceptable when installing a reinforcement belt. The rod is bent to reinforce every corner of the strip foundation, including the approaches to internal partitions, with a consistent approach into the surrounding walls.
This article’s video will explain the ins and outs of corner reinforcement and highlight the significance of correctly reinforcing corner joints.
When more than one reinforcement belt is inserted into the foundation, vertical fixation—that is, the welding or tying of vertical rods—is carried out in addition to horizontal coupling, determining the spacing between the horizontal belts.
Concreting
The strip foundation is concreted in sections over the course of one day. The calculated design proportions of concrete for the strip foundation should never be altered as this will affect the base’s strength.
Since it is preferable to pour the solution straight into the formwork, a spot must be set up where the mixer trucks can drive straight to the trench. Galvanized gutters should be used to deliver concrete to isolated locations.
The mortar is poured into the trench in one direction in layers no thicker than 0.5 m, regardless of the type of concrete used for the strip foundation. After the previous layer of mortar has been compacted and tapped along the formwork walls, the next layer is poured. One layer of a shallow strip foundation is poured.
Air temperature during work | Maintenance measures | Formwork removal period: (hour) |
+30 0 C | supplementary irrigation | 72 |
+20°C | does not require | 96 |
+10 0 C | does not require | 240 |
0 | heating and insulation required | 672 (4 weeks) |
If needed, the formwork is taken down and steps are taken to waterproof the foundation surfaces once the concrete has set. Following that, backfilling is done.
Calculation of concrete for the foundation
The proportion of components in various concrete grades (cement M-400)
Concrete grade | Material ratio (Cement x Sand x Crushed stone) |
Cement consumption per 1m3 of concrete (kg.) |
M-100 | 1 x 4.6 x 7.0 | 170 |
M-150 | 1 x 3.5 x 5.7 | 200 |
M-200 | 1 x 2.8 x 4.8 | 240 |
M-250 | 1 x 2.1 x 3.9 | 300 |
M-300 | 1 x 1.9 x 3.7 | 320 |
Every structure needs a monolithic reinforced concrete strip foundation to be stable and long-lasting. This article walks you through every step of the construction process, from setting up the formwork and preparing the site to pouring and curing the concrete. We strive to make the process simple and manageable with step-by-step instructions and professional advice, guaranteeing that your foundation is robust, long-lasting, and constructed to last.
Recommendations for calculations
Specifics of each foundation’s calculation are unique. You should get assistance from experts if you lack the necessary knowledge and abilities. You can use the online calculator to enter the data and determine the recommended dimensions that have been adjusted for the freezing depth for average calculations.
Even though every foundation has a different objective, there are a few things that all of them have in common that should be noted:
- Any foundation is deepened below the level of soil freezing by 10% of the height.
- On loose soils, in areas with a moderate climate, it should be deepened to a depth of up to 1 m.
- In northern latitudes with slightly heaving soils, the foundation is dug to a depth of up to 2 m.
It is not advisable to go overboard in your quest to create a house’s foundation as sturdy as possible. Excavating a pit further than required won’t improve the building’s dependability; instead, it will drive up material costs dramatically. Furthermore, there will be an increase in the area where soil and groundwater physical horizontal pressure is applied.
The amount of concrete required for a strip foundation can be easily determined with a project or drawing of the foundation. Since concrete is sold in cubic meters, the volume of the formwork must be determined.
One can multiply to obtain this value:
- width of the foundation;
- perimeter of the house, including load-bearing partitions;
- height of the formwork.
Calculation of the strip foundation
Setting up a monolithic reinforced concrete strip foundation is an essential first step in making sure your building is sturdy and stable. By beginning with exact measurements and careful site preparation, you set the stage for a successful project. In order to create the trench that will house the foundation, the excavation must be done carefully in accordance with the design specifications.
Formwork, which serves as a mold for the concrete, is installed next. Since the formwork will shape the foundation, it is imperative to make sure that it is accurate and sturdy. Steel bar reinforcement comes next, giving the concrete more strength and enabling it to endure a variety of stresses over time.
The next crucial step is to pour the concrete. To prevent weak spots, this should be done consistently. It’s also critical to properly vibrate the concrete to eliminate air pockets. Concrete must be given enough time to cure after it is poured in order to reach its maximum strength and stability.
Expert guidance highlights how crucial it is to pay close attention to details at every stage of the procedure. Problems later on can be avoided with routine inspections and modifications at each stage. Furthermore, utilizing premium materials and adhering to advised procedures will help create a foundation that endures over time.