What are the key factors to consider when choosing between shallow and deep foundations? (2024)

Consider soil conditions, load characteristics, and foundation depth when choosing between shallow and deep foundations. Evaluate various foundation types based on project requirements. Assess foundation performance for reliability and safety. Implement maintenance plans for optimal longevity. Share additional insights to enhance decision-making.

Yes of course! Although deep foundations can carry more load, deep foundations cannot be utilized in every structure due to their high cost. There the soil conditions must be assessed to find the soil properties so that a suitable foundation type can be determined.

Para definicao no tipo de fundacao a ser utlizado e fundamental a realizacao de estudos geotecnicos . Um dos estudos fundamentais e a investigacao geotecnica por sondagem spt , onde obtem-se o indice de resistencia a penetracao Nspt por cada avanco de camada , o nivel freatico e tipologia do solo por cada metro de avanco conforme tabela de classificacao dos solos sucs. Outra investigacao e a coleta de amostra nao trabalhada para caracterizacao dos parametros fisicos e geomecanicos. Apartir dai e possivel passar os resultados ao engenheiro calculista para que atraves de software especifico possa definir o tipo de fundacao a ser utlizado

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First and most important thing is to understand the project limitations and allowable movement. I have recommended thousands of foundations in my career, both shallow and deep.Generally, deep foundations will move less, cost more, can hold more weight and support a structure over unsuitable soils such as expansive or collapsible soils.Deep foundations are typically driven or drilled to a hard uniform strata or rock or use skin friction to support the loads. We used friction piles for a 23 story hotel in California when we finished the site investigation and determined that the sand was well over 100-feet deep.Other factors for consideration are soils with expansive, collapsible, soft, organic debris characteristics, groundwater depth.

Consider Soil Conditions, excavation level, foundation type. Evaluate & assess soil characteristics to determine the appropriate soil type for designing to earthquakes.

Absolutely!To design the foundation relevant loads must be calculated with safety factors. Then the foundation design can be carried out.

Adicionalmente al tipo de carga, es importante condicionar el uso de las cimentaciones superficiales en el caso de tener cargas sísmicas importantes en suelos potencialmente licuables.En un suelo potencialmente licuable, si la probabilidad de manifestación severa de licuación (Towhata et al. 2016), se debe desaconsejar el uso de cimentaciones superficiales.

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Analyse the pros & cons of shallow & deep foundations. Evaluate the bearing capacity for the soil. Provide multi options and consider the economy, safety, reliabity & workability for each.

Considering load characteristics involves evaluating the magnitude, distribution, and nature of the loads the foundation will bear. This includes analyzing both vertical loads from the structure itself and lateral loads from external factors like wind or seismic events. Understanding these factors is essential for determining the appropriate foundation type and design to ensure structural stability and safety over the long term.Shallow foundations are ideal for structures with light, symmetrical, and steady loads, minimizing stress on the soil. Conversely, deep foundations are better suited for structures with heavy, asymmetrical, or dynamic loads, providing enhanced stability and resistance against lateral forces.

Foundation depth is a crucial factor to consider as it determines how effectively the foundation can distribute loads and withstand external forces. The appropriate depth depends on soil conditions, load characteristics, and structural requirements, ensuring stability and long-term performance of the building.Foundation depth impacts load transfer, soil-structure interaction, and construction cost. Shallow foundations, with smaller depth, offer simpler, cheaper construction but are prone to settlement and frost heave due to larger soil contact area. In contrast, deep foundations, with greater depth, entail complex, costly construction but provide better load transfer and are less affected by surface conditions.

Foundation depth is crucial to ensure that the footings transfer the load to the desired soil layer satisfying the following conditions:1- Settlement are within the allowable limit.2- No differenetial settlement occurs.3- No soil liquefaction.4- stresses acting on soil are within the bearing capacity limits & do not make any tension on soil.5- Resistant to uplift & lateral loads.6- Prevent water infiltration to the building.7- Ease of maintenance & repair.8- Reliable.

For one instance, in a soil area which is more susceptible to differential settlement it is recommended not to use pad foundations and it is better to use mat or raft foundations.

Foundation type refers to the specific design and construction method used to support a structure and transfer its loads to the underlying soil or rock. There are various types of foundations, including shallow foundations such as strip footings, raft foundations, and pad foundations, which spread loads horizontally near the surface. Deep foundations, on the other hand, include pile foundations, drilled piers, and caissons, which transfer loads vertically to deeper, more stable soil or rock layers. The choice of foundation type depends on factors such as soil conditions, load characteristics, and project requirements, with each type offering unique advantages and considerations in terms of construction, performance, and cost.

Footings can be calssified into two main categories:1- Shallow Foundations Shallow Foundations are footings having excavation level less than or equal to the footing depth. Shallow foundations include: isolated footings, strip footings, strap footings, combined footings, mat foundations.2- Deep footings Deep footings are footings where excavation level is greater than the footings width. Deep footings include, piles, micro piles foundations & pier foundations.

Foundation performance encompasses the expected behavior and outcomes of the foundation under different loads and environmental conditions. It involves assessing reliability, safety, and durability, ensuring adherence to design criteria and standards. Monitoring during and after construction helps compare predicted versus actual performance, addressing any issues compromising structural integrity. Shallow and deep foundations present distinct performance characteristics and challenges influenced by site and load conditions, foundation type, and construction quality.

Foundation Performance should satisfy the following:1- Settlement are within the allowable limit.2- No differenetial settlement occurs.3- No soil liquefaction.4- stresses acting on soil are within the bearing capacity limits & do not make any tension on soil.5- Resistant to uplift & lateral loads.6- Prevent water infiltration to the building.7- Ease of maintenance & repair.8- Reliable.