Shallow Foundations Introduction Design Requirements Failure Modes of Shallow Foundations Bearing Capacity for Shallow Foundations Bearing Capacity Equation • Bearing Capacity on Sand from Standard Penetration Tests (SPT) • Bearing Capacity from Cone Penetration Tests (CPT) • Bearing Capacity from Pressuremeter Tests (PMT) • Bearing Capacity According to Building Codes • Predicted Bearing Capacity vs. Load Test Results | Chai J. Shallow Foundations. Bridge Engineering Handbook. Ed. Wai-Fah Chen and Lian Duan Boca Raton CRC Press 2000 31 Shallow Foundations Introduction Design Requirements Failure Modes of Shallow Foundations Bearing Capacity for Shallow Foundations Bearing Capacity Equation Bearing Capacity on Sand from Standard Penetration Tests SPT Bearing Capacity from Cone Penetration Tests CPT Bearing Capacity from Pressuremeter Tests PMT Bearing Capacity According to Building Codes Predicted Bearing Capacity vs. Load Test Results Stress Distribution Due to Footing Pressures Semi-infinite Elastic Foundations Layered Systems Simplified Method 2 1 Method Settlement of Shallow Foundations Immediate Settlement by Elastic Methods Settlement of Shallow Foundations on Sand Settlement of Shallow Foundations on Clay Tolerable Settlement Shallow Foundations on Rock James Chai Bearing Capacity According to Building Codes Bearing Capacity of Fractured Rock Settlement of Foundations on Rock California Department of Transportation Structural Design of Spreading Footings Introduction A shallow foundation may be defined as one in which the foundation depth D is less than or on the order of its least width B as illustrated in Figure . Commonly used types of shallow foundations include spread footings strap footings combined footings and mat or raft footings. Shallow foundations or footings provide their support entirely from their bases whereas deep foundations derive the capacity from two parts skin friction and base support or one of these two. This chapter is primarily designated to the discussion of the bearing capacity and settlement of shallow foundations although structural considerations for footing design are briefly addressed. Deep foundations for bridges are discussed in Chapter 32. 2000 by CRC Press LLC P FIGURE Definition sketch for shallow footings. TABLE Typical Values of Safety Factors Used in Foundation Design after .
