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This is a step most builders and doityourselfers do not spend enough time on. Let's say your lot is wooded. After the trees are removed the soil is broken up and raked for as much as 2' or more. Some stumps can go as much as 6' into the ground. This ground needs to be compacted before you put a foundation on it. Or, it will compact after, causing unwanted settling of your foundation. Don't let the dozzer driver tell you he compacted with the dozzer the reason dozzers can travel on mud where you cannot walk is because the tracks dissipate the weight out over a larger surface. The ground needs to be compacted in layers. Wet ground will not compact... people pour slabs on mud all the time. A drying agent must be added or it will have to be dryed over time. Some soil which has a high plasticity index (PI) will need to be excavated and good select fill brought in and compacted. Another option for this problem would be to have drilled bell bottom piers incorporated into your foundation design. Bottom line is your foundation needs to be designed by an engineer and those instructions followed by a builder who does not cut corners... Good luck with that one!
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What kind of building rests on a foundation?
Foundation is the underground or the substructure part of a building that transmits the load of the super structure to the ground safely. it is the lower part of building on which the whole structure rests. it may be made up of stone masonary, PCC or RCC. depending the width to depth ratio it may be a shallow foundation or a deep foundation. shallow foundations are used for smaller structures and shallow foundations are used for multistoried buildings where the load carried by soil is more.
Why you have to use raft foundation?
A raft foundation, also known as a mat foundation, is a type of shallow foundation that is used in construction to distribute the weight of a building or structure evenly across a large area of soil. It is typically used when the soil's load-bearing capacity is relatively low, or when the building's loads are heavy and spread over a wide footprint. Here are some reasons why a raft foundation might be used: **Uniform Load Distribution**: Raft foundations are designed to distribute the load of a building uniformly over a larger area of soil. This helps prevent localized settlement that could occur with point loads or strip foundations. **Poor Soil Conditions**: If the soil at a construction site has low bearing capacity, meaning it can't support heavy loads without excessive settlement or deformation, a raft foundation can help distribute the loads over a larger area, reducing the pressure on the soil. **Variability in Soil**: In some cases, the soil properties might vary across the construction site. A raft foundation can help mitigate the effects of differential settlement, where one part of the building's foundation settles more than another due to varying soil conditions. **Heavily Loaded Structures**: Raft foundations are commonly used for buildings with heavy loads, such as multistory buildings, warehouses, or industrial facilities. The broad contact area with the soil helps prevent excessive stress on the ground. **Reduced Foundation Depth**: Raft foundations are shallow foundations, meaning they are located closer to the ground surface compared to deep foundations like piles or caissons. This can save excavation costs and make construction more efficient. **Economical Solution**: In some cases, a raft foundation might be more cost-effective compared to using deep foundations, especially when the structure's loads are spread out over a large area. **Stability in Poor Soil**: If the soil has a potential for lateral movement (such as in areas with high groundwater or seismic activity), a raft foundation can provide stability by distributing lateral forces over a larger area. **Preventing Differential Settlement**: In situations where multiple structures are built close to each other, a raft foundation can help prevent differential settlement that might occur if different structures have different foundation systems. It's important to note that while raft foundations offer several advantages, they might not be suitable for all construction scenarios. Factors such as soil type, building loads, local climate, groundwater levels, and structural design will all influence whether a raft foundation is the appropriate choice. Engineering professionals, including structural and geotechnical engineers, play a crucial role in determining the most suitable foundation type for a specific project based on site conditions and building requirements.
Define pressure bulb in soil mechanics?
Shape: The pressure bulb is typically depicted as a three-dimensional shape, often resembling an inverted cone or pyramid. It extends downwards from the base of the loaded area or foundation into the soil. Distribution: Within the pressure bulb, the pressure is not uniformly distributed. It is highest at the base of the loaded area and decreases with depth. The pressure distribution is influenced by factors such as the shape and size of the foundation, the load magnitude, and the properties of the soil. Depth: The depth of the pressure bulb varies depending on the characteristics of the foundation and the soil. Deeper foundations will have deeper pressure bulbs.
What is the Concrete slab at entrance of building?
The slab is part of the overall foundation and footing system of the building. If it is outside, then it doesn't need to be water-proof or damp-proof. All interior foundation walls need to be water-proofed or damp-proofed depending on the hydrostatic pressure, found in the surrounding earth. Foundations and slabs-on-ground should be placed on good, compacted soil, or other acceptable aggregates. A solid slab should be a minimum 100mm thick.
What is ordinary strip foundation?
Load Distribution: The primary function of a strip foundation is to distribute the load from the building's walls evenly to the underlying soil. This prevents excessive settlement or soil bearing capacity issues. Width and Depth: The width and depth of a strip foundation depend on factors such as the building's load, the type of soil, and local building codes. The width is typically greater than the width of the wall it supports. The depth is determined by the frost depth (to prevent frost heave) and the soil's bearing capacity. Reinforcement: In some cases, steel reinforcement bars (rebar) may be added to the concrete strip to enhance its tensile strength and overall stability. Footing Dimensions: The footing, or the bottom part of the strip foundation, is wider and serves as the load-spreading element. It is usually wider than the wall it supports to provide stability. Construction Process: Strip foundations are typically cast directly on the ground or on a shallow trench. The trench is excavated to the required depth and dimensions, and then concrete is poured into the trench to create the foundation. Use in Residential and Light Commercial Buildings: Strip foundations are commonly used in residential buildings, small commercial structures, and other low- to medium-rise buildings. They are suitable for structures with relatively light loads. Cost-Effective: Strip foundations are cost-effective and relatively simple to construct, making them a popular choice for a wide range of building types.
What has the author W L Schroeder written?
W. L. Schroeder has written: 'An evaluation of Palouse clay as a foundation material' -- subject(s): Foundations, Soil mechanics, Testing, Clay 'Soils in construction' -- subject(s): Foundations, Soil mechanics, Building 'Application of geotechnical data to resource planning in southeast Alaska' -- subject(s): Soil mechanics, Slopes (Soil mechanics), Soil stabilization
Why is there a need for different building foundations?
According to soil condition, load, environmental conditions we need different types of foundations.......
What are the advantages and disadvantages of soil stabilization?
advantages of soil stabilization by waste plastic fiber.
What is the Deep foundations?
Deep foundations are structural components used to transfer loads from a building or structure into the earth when shallow foundations are not feasible due to weak soil conditions or when the required depths are beyond what shallow foundations can provide. Examples include piles, drilled shafts, and caissons. These elements are typically embedded deep into the ground to provide stability and support for the structure above.
What has the author M Budhu written?
M. Budhu has written: 'Foundations and earth structures' -- subject(s): Foundations, Soil mechanics 'Soil mechanics and foundations' -- subject(s): Foundations, Soil mechanics
What does mechanical stabilization of a soil accomplish?
improve the drainage or compaction characteristics of soil
How do you define soil?
define soil crusting
What has the author Jacobo Bielak written?
Jacobo Bielak has written: 'Modal analysis for building-soil interaction' -- subject(s): Foundations, Mathematical models, Modal analysis, Soil mechanics
Are the roots of fig trees dangerous to foundation?
The roots of any tree can pose a danger to building foundations, Fig trees can be quite large, but it'll depend on the proximity to the building and, presumably, the type of soil and the foundations. There are structural engineers who can survey the property and advise of any serious risk.
Where can one find information on soil stabilization?
DirtGlue is great for soil stabilization. On their site you will find all the information you need including documents and more about the industry. If you need help finding the website go to Google and search DirtGlue.
What has the author Richard Delafield written?
Richard Delafield has written: 'Memoir on foundations in compressible soils' -- subject(s): Foundations, Soil mechanics 'Memoir on foundations in compressible soils' -- subject(s): Foundations
What is soil-building process?
building up soil
