Subgrade Modulus

Is there anyone here who knows the default value or acceptable value of subgrade modulus to be use in design when soil investigation is not available? Assuming seismic design category (SDC) D.




  • Books such as "Foundation Analysis and Design" by Joseph Bowles, McGraw Hill, Fourth Edition, Table 9-1 list the following values in Kips per cubic feet (Values shown in parentheses are in kN per cu.metre)

    Loose Sand - 30 to 100 (4800 to 16000)
    Medium Dense Sand - 60 to 500 (9600 to 80000)
    Dense Sand - 400 to 800 (64000 to 128000)
    Clayey medium dense Sand - 200 to 500 (32000 to 80000)
    Silty Medium Dense Sand - 150 to 300 (24000 to 48000)

    Clayey soil - 75 to 300 or greater (12000 to 48000 or greater)

  • Sir Can you Recommend me what subgrade modulus shall be used in my model if no data are available in designing tie-beam? its only two stories so its so expensive for me to cunduct a soil test.