Rubble concrete strip foundation: characteristics, technology

You may encounter terms like "rubble concrete strip foundation" if you’re new to the field of concrete foundations. Though it may seem a little technical, rest assured that this is a simple and useful solution that is applied to many different construction projects. This kind of foundation creates a sturdy, dependable base for buildings by mixing concrete with conventional rubble.

The versatility of rubble concrete strip foundations allows them to adapt to different soil conditions and uneven terrain. Building professionals can create a foundation that is both flexible and durable by combining concrete and rubble. This mixture is a common option for many different kinds of buildings because it supports the structure above and helps distribute weight more evenly.

Technology-wise, the procedure is very simple to use. It entails filling foundation trenches with a layer of rubble and then covering it with concrete. By providing reinforcement, the rubble increases stability and strength. Due to its adaptability to various site conditions and use of easily obtained materials, this method is not only effective but also economical.

All things considered, rubble concrete strip foundations provide a useful and adaptable answer for a variety of building requirements. Having a solid understanding of this kind of foundation will help you make wise decisions and guarantee a strong base for your project, whether you’re building a new house or a modest outbuilding.

Characteristic	Description
Definition	Rubble concrete strip foundation is a type of foundation made by combining rubble (like stones or bricks) with concrete to create a sturdy base for buildings.
Strength	It"s strong and durable, providing good support for structures, especially in areas with varying soil conditions.
Construction Process	The process involves laying down a trench, filling it with rubble, and then pouring concrete over the rubble to form a solid strip.
Cost	Generally cost-effective because it uses locally available materials like rubble, which can be cheaper than buying all-new materials.
Advantages	Good load distribution, effective in stabilizing foundations in uneven soil, and often more affordable.
Disadvantages	Can be labor-intensive and requires careful construction to ensure the rubble is well-packed and the concrete is properly cured.
Usage	Commonly used in residential construction and in areas where materials are easily available and soil conditions are less predictable.

Main characteristics

The category of shallow structures includes rubble and rubble concrete strip foundations, which are primarily used for one-person, hand-built construction of low-rise buildings (1-2 stories). These kinds of structures work incredibly well when building a private home in areas with high groundwater and heaving foundations.

Types of foundations made of natural stone

Utilizing building materials that are commonly found in a given area to the fullest extent possible with rubble concrete foundations greatly boosts the financial advantages of utilizing this kind of structure.

There are two methods for creating rubble and rubble concrete strip foundations, depending on the properties of the soil base:

• in formwork – for weak soils (sandy, sandy loam);
• in dense soils – without formwork: the masonry is carried out by thrusting along the walls of the trench;

The formwork is constructed from shields that are knocked together from edged boards that are 40 mm thick. Flat slate or leftover chipboard can also be utilized.

Rubble

A structure composed of naturally occurring stones with an irregular shape resembling two roughly parallel surfaces is called a rubble foundation (beds).

The rocks listed below are utilized to make rubble structures:

• limestone;
• tuff;
• granite;
• sandstone;
• cobblestone and other similar materials.

Stones used in masonry typically weigh up to 30 kg and have calibrated dimensions of 20 by 30 cm. Larger rubble is pre-prepared by splitting it into the necessary fractions and modifying its geometric parameters so that it takes the form of a parallelepiped. This kind of art is referred to as plinth.

For plinth setting of masonry stones, a 4.8 kg sledgehammer is typically used; for more exact processing, a cam—a 2.3 kg pointed hammer—is employed. During rubble masonry, the same instrument is used to chip or settle stones.

Apart from the devices mentioned earlier, the same tools are utilized for building structures as they are for bricklaying. It is advised to use rubble masonry for small construction volumes and structures that are not subjected to large tensile stresses. Additionally, rubble is an inexpensive local material.

Mortars are used in masonry, and their grades have to match the requirements listed in the following table.

Rubble concrete

A strip rubble concrete foundation consists of a concrete mobile mixture into which rubble stones are pressed evenly in horizontal rows. The amount of natural stone should correspond to half of the total volume of the structure.

With one exception—using unsplit stones is allowed—rubble concrete structures are subject to the same regulations as rubble masonry. Nonetheless, the width of the structure being built should not be greater than one-third of the geometric size of the rubble used.

Another crucial point: detachable panel formwork is always used during the construction of a concrete rubble foundation, irrespective of the state of the soil. One of the advantages is that the cost of building concrete rubble structures is comparable to that of installing monolithic strip structures, but it is less expensive than that of comparable rubble structures in volume.

Foundation calculator

Materials

The masonry’s physical and mechanical characteristics are what ultimately dictate how well a rubble and rubble concrete foundation performs as a supporting structure. To select the appropriate materials for building a low-rise private home’s foundation, one must comprehend and be aware of how a given kind of material will respond to different building operating situations.

Concrete mix

Which type of concrete is suggested for a strip foundation when building rubble concrete structures?

Depending on the number of stories, kind of soil, and intended use of the building, building codes and regulations for strip monolithic structures allow for the following concrete grades:

• M150 — as the main foundation for light structures (terraces, verandas, outbuildings, etc.);
• M200 – arrangement of bases in low -rise construction (one -story buildings, blind area, stairs);
• M300 – for bases and monolithic floors (two -story cottages, monolithic walls, stairs);
• M350 – monolithic strip structures for difficult operating conditions (construction on slopes, movable soils, high levels of GV):
• M400 – arrangement of bases in marshy soils and seismic hazardous regions.

In actuality, the M150–M200 grades are most frequently utilized for the installation of rubble and rubble concrete systems. Crushed stone used in concrete mortar should not be larger than 3.0 cm, and the mortar should move between 5 and 7 cm (cone slump).

Plasticizers, with an emphasis on the design documentation and the operational properties of the completed structure recommended by this document, must be added to the concrete mixture in order to ensure sufficient mobility.

In compliance with SNiP 2.02.01-83, concrete for a strip foundation made of natural stone is calculated.

A rubble concrete structure is composed of 50% natural stone and 50% concrete, as was previously mentioned. As a result, we multiply the length, height, and width to determine the structure’s total volume. We then divide that volume in half and add 10% to 15% while accounting for the typical consumption of each kind of material (consumption tables).

Natural stone

Natural stone used in construction is separated into the following categories based on the surface treatment method:

• torn rubble — unprocessed stone with sharp corners and no flat edges;
• bedded rubble — natural material with two parallel planes (beds);
• rubble slab — stone in the shape of a slab;
• rubble under a bracket — with roughly hewn side surfaces;
• hewn rubble — stone with projections from 0.2 to 2.0 cm; permissible profile height — more than 12 cm.

Roughly processed and unprocessed stone from hard rocks is most frequently used for the construction of rubble concrete systems, and it must have the following technical qualities:

1. Density not less than 1800 kg/m3 .
2. Fraction size 150–500 mm. In some cases, a size of 500–1000 mm is allowed.
3. The content of clay inclusions in the total volume of rubble should not exceed 2%.
4. Compressive strength of natural stone should correspond to grades from 100 to 1400.
5. Frost resistance F15—F300.
6. Water resistance groups – 1.0; 0.9; 0.75; 0.6.

Advice: — Natural stone needs to be cleaned of dirt, moistened with water, and inspected for cracks before beginning any masonry work on the building of a rubble concrete structure.

Calculation of the strip foundation

Design

The width and depth of the structure’s sole are the first parameters to be determined in the bottlenut foundation calculations.

The following variables determine how these values are defined:

• structure design (the presence of a basement, engineering networks, etc.);
• nature and size of loads;
• terrain;
• geological conditions;
• hydrogeological conditions;
• climatic conditions (freezing depth and t. P.).

However, the structure’s sole depth should prevent the soil beneath the structure from freezing to the greatest extent possible and guarantee the base’s dependable operation under the highest calculated conditions (stretching, compression, etc.).

Calculation of MZLF by Sajin

For many building projects, rubble concrete strip foundations are a useful and affordable option. These foundations are a popular option for many kinds of buildings because they combine the strength of rubble with the durability of concrete. Their sturdy nature is especially helpful in places where the soil is unstable or where money is tight.

The technology underlying rubble concrete strip foundations is quite simple, yet it works incredibly well. Both structural strength and resilience are added to the foundation by embedding rubble within a concrete matrix. Because the rubble acts as a filler material, requiring less concrete than traditional methods, this method also permits faster construction.

The versatility of rubble concrete strip foundations is one of their main benefits. They can be adjusted to meet various soil conditions and construction needs. Their strength and cost-effectiveness, along with their flexibility, make them an excellent option for a variety of construction projects. Regardless of the size of the structure you’re working on, a foundation of this kind can offer the stability and support required for long-term functionality.

All things considered, many builders consider rubble concrete strip foundations to be a wise choice. Their dependability in contemporary construction is ensured by their practicality and durability. If you’re thinking about using this kind of foundation for your project, you’ll gain from its demonstrated efficacy and versatility, which will guarantee a strong foundation for your building.

For many construction projects, a rubble concrete strip foundation is an efficient and economical option since it combines the practicality of using rubble with the durability of concrete. This article will examine the main characteristics of rubble concrete strip foundations, such as their stability and strength, as well as the methods and technologies employed in their construction. Knowing about this type of foundation can help you make wise decisions and provide a sturdy, long-lasting base for your project, regardless of whether you’re building a new home or strengthening an existing one.

Video on the topic

Strip foundation with rubble stone

making a rubble foundation.

How the rubble foundation was poured

Foundation soles | What are they for?