$***"$In civil engineering, what are the primary factors influencing the choice between shallow and deep foundations for building structures? Discuss the soil characteristics, building loads, and site constraints that engineers must consider when selecting the appropriate foundation type. Explain the advantages and limitations of shallow foundations, such as spread footings and mat foundations, compared to deep foundations like piles and caissons. How do construction costs, time constraints, and environmental factors impact this decision$-$making process? Provide examples of real$-$world projects where each foundation type is most suitable."

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