Unit Weight

Bulk Unit Weight

Defines Bulk Unit Weight ( $\begin{array}{l}\gamma_b\end{array}$ ) for main calculation
Robertson and Cabal, 2010

$\begin{array}{l}\displaystyle \gamma_b=(0.27 \cdot log(R_{f})+0.36 \cdot (q_t or q_c) + 1.236) \cdot G_s / 2.65 \cdot 9.81 \cdot \gamma_w\end{array}$

Dry Unit Weight 1 (Sands)

Dry Unit Weight 1 ( $\begin{array}{l}\gamma_{dry}\end{array}$ ) in Dry_Unit_Weight_1 is defined as:

$\begin{array}{l}\displaystyle \gamma_{dry}=C_1 \cdot log(q_{t1})+C_2\end{array}$

Mayne (2007), NCHRP Synthesis 368 p 31

Where:
$\begin{array}{l}C_1\end{array}$ is 1.89 in the published formula, and is stored in the Dry_Unit_Weight_1_C1 field.
$\begin{array}{l}C_2\end{array}$ is 11.8 in the published formula, and is stored in the Dry_Unit_Weight_1_C2 field.

The constants are stored on CPT_POINT_CORRELATION_PARAMETERS and CPT_PROJECT_CORRELATION_PARAMETERS tables.

This correlation of $\begin{array}{l}V_S\end{array}$ is calculated only when the Soil_Type_1 field value on the CPT_DATA table is Coarse or Mixed for that row.

Saturated Unit Weight 1

Saturated Unit Weight 1 ( $\begin{array}{l}\gamma_{sat}\end{array}$ ) in Saturated_Unit_Weight_1 is defined as:

$\begin{array}{l}\displaystyle \gamma_{sat}=C_1 \cdot log(V_s)-C_2 \cdot log (z)\end{array}$

Mayne (2007), NCHRP Synthesis 368 p 31

Where:
$\begin{array}{l}V_s\end{array}$ is in m/s and $\begin{array}{l}z\end{array}$ is in m
$\begin{array}{l}C_1\end{array}$ is 8.32 in the published formula, and is stored in the Saturated_Unit_Weight_1_C1 field
$\begin{array}{l}C_2\end{array}$ is 1.61 in the published formula, and is stored in the Saturated_Unit_Weight_1_C2 field
$\begin{array}{l}z\end{array}$ is Depth
$\begin{array}{l}V_S\end{array}$ is taken from the first of these fields with data: Shear_Wave_Velocity_Extrapolated or Shear_Wave_Velocity_1

The constants are stored on CPT_POINT_CORRELATION_PARAMETERS and CPT_PROJECT_CORRELATION_PARAMETERS tables.

This correlation is applicable to all soil types.

Saturated Unit Weight 2

Saturated Unit Weight 2 ( $\begin{array}{l}\gamma_{sat}\end{array}$ ) in Saturated_Unit_Weight_2 is defined as:

$\begin{array}{l}\displaystyle \gamma_{sat}=C_1 \cdot log(f_s)+C_2 \cdot G_s-C_3\end{array}$

Mayne (2007), NCHRP Synthesis 368 p 32

Where:
$\begin{array}{l}f_s\end{array}$ is in kPa.
$\begin{array}{l}C_1\end{array}$ is 2.6 in the published formula, and is stored in the Saturated_Unit_Weight_2_C1 field.
$\begin{array}{l}C_2\end{array}$ is 15 in the published formula, and is stored in the Saturated_Unit_Weight_2_C2 field.
$\begin{array}{l}C_3\end{array}$ is 26.5 in the published formula, and is stored in the Saturated_Unit_Weight_2_C3 field.
$\begin{array}{l}G_s\end{array}$ is Specific Gravity of Solids, typically 2.4 to 2.9, and is stored in the Specific_Gravity_of_Solids field on CPT_PROJECT_CORRELATION_PARAMETERS.

The constants are stored on CPT_POINT_CORRELATION_PARAMETERS and CPT_PROJECT_CORRELATION_PARAMETERS tables.

This correlation is applicable to all soil types.

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