Program AU1 – AS1170.4 response spectrum generator

QUAKE ADVICE_Seismic Design Response Spectrum Report

Generation of AS 1170.4-2007 (Amdt 2018) Response Spectra

1. Input Parameters:

No. of Boreholes:

I. Probability Factor * Hazard Design Factor, k_pZ:

II. Shear Wave Velocity (SWV) Model:
III. Energy Ratio (N₆₀/N_measured):

IV. Soil Characteristics:

Note:

The program offers two selection options for the soil types: "Sand Only" and "User Specified". If the site contains solely of sandy soil, you can choose the "Sand Only" option. Otherwise, you should select the "User Defined" option.
The "Sand Only" option necessitates providing the thickness and Standard Penetration Test (SPT-N) values of each soil layer. When selecting this option, the program utilizes the "Ohta & Goto" shearwave velocity model as default soil models.
The "User Defined" option requires providing the thickness, SPT-N, soil type, soil age, and water content for each soil layer. When selecting this option, the program offers the "Imai & Tonuchi" and "PEER" shearwave veocity models.
If all entries to a particular “thickness” column are left blank, the program will automatically fill in a default thickness of 1.5 m.
SPT-N values obtained from testing very stiff materials need to be corrected to a penetration depth of 300 mm. For example, if an SPT-N value of 50 is obtained at a penetration depth of 100 mm, it should be corrected to 150. When SPT-N values are not available in the borelog, they can be determined from the soil description, as shown in the table below.
When selecting the "User Defined" option, enter the soil type according to the specifications in AS 1726: "GP, GW, GM, GC, SP, SW, SM, SC, ML, MH, CL, CI, CH". If the soil type is unknown, it is suggested to use 'SW' for coarse soil and 'MH' for fine soil.
Soil age (when required): enter 'Q' for Quaternary, 'H' for Holocene, and 'P' for Plesitocene for each layer. If the soil age is unknown, it is suggested to use 'Q'.
Water content (when required): enter according to the specifications in AS 1726 as shown in the table below. If the water content is unknown, it is suggested to use 'M' for coarse soil and 'W1' for fine soil.
The table can be filled manually or by performing a copy (CTRL+C) and paste (CTRL+V) of data from Excel spreadsheet.

	Borehole 1		Borehole 2		Borehole 3		Borehole 4		Borehole 5		Borehole 6		Borehole 7		Borehole 8		Borehole 9		Borehole 10		Borehole 11		Borehole 12		Borehole 13		Borehole 14		Borehole 15		Borehole 16		Borehole 17		Borehole 18		Borehole 19		Borehole 20
	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N	Thickness(m)	SPT-N
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40

2. Results: Site Class and Design Response Spectrum

I. Soil Profile with SPT-N Value:

Figure 1: SPT-N Profile.

II. Average Shear Wave Velocity (V_s) and Site Period (T_s):

This section focuses on the analytical modeling of the soil columns to calculate shear wave velocity and site period for each soil columns (boreholes). The SWV is determined from soil characteristics using the shearwave velocity conversion models as presented in Table A1. Similarly, the density of the soil layers are determined using Table A2. Both Table A1 and A2 are provided in the Appendix. Once the shearwave velocity of each layer of soil is determined, Eqs. (1) and (2) are used to calculate the average shearwave velocity and site period for the borehole considered. The results for the borehole defined as an input are shown in Table. Finally, from the site period determined, the AS 1170.4-2007 (Amdt 2018) site class or ground type is determined as shown in Table 2.
$$ {V_s = \frac{H_s}{ \sum^n_{i=1} \dfrac{d_i}{SWV_{i}} }}\tag{1}$$ $$ {T_s = \frac{4 \times H_s}{V_s}}\tag{2}$$ Where: H_s = total depth of soil; n = number of soil layers; d_i = thickness of soil layer 'i' and N_{60_i} = corrected SPT-N value (corresponding to 60% energy efficiency) of soil layer 'i'.

Table 1: Average Shear Wave Velocity and Site Period of Soil of each Boreholes.

Borehole No.	Average Shear Wave Velocity (m/sec)	Site Period (sec)

Table 2: Soil site classification.

III. Seismic Design Response Spectrum:

a. Response Spectral Acceleration (RSA) and Acceleration Displacement Response Spectrum (ADRS) Diagram:

Figure 2: RSA Diagram.

Figure 3: ADRS Diagram.

Table 3: Response Spectral Acceleration (RSA) and Response Spectral Displacement (RSD) of soil.

T (sec)	RSA-soil (g)	RSD-soil (mm)

3. References:

Standard, A. (2007). AS 1170.4-2007 (Amdt 2018).Structural Design Actions, Part 4: Earthquake Actions in Australia..

Sabatini, P.J., Bachus, R. C., Mayne, P. W., Schneider, James A., Zettler, T. E. (2002). Geotechnical Engineering Circular No. 5: Evaluation of Soil and Rock Properties, Report no: FHWA IF-02-034. Federal Highway Administration, Washington, DC United States.

Wair, B. R., DeJong, J. T., & Shantz, T. (2012). Guidelines for estimation of shear wave velocity profiles. Pacific Earthquake Engineering Research Center.

APPENDIX:

Table A1. SPT-N to Shear Wave Velocity conversion.

Table A2. Correlation of soil density with soil type and water content.

Disclaimer

The authors assume no responsibility for any injury, damage, liability, negligence and/or otherwise to any individual or property from the use or application of any of the methods, products, instructions, or ideas contained in the material herein.

	Borehole 1				Borehole 2				Borehole 3				Borehole 4				Borehole 5				Borehole 6				Borehole 7				Borehole 8				Borehole 9				Borehole 10				Borehole 11				Borehole 12				Borehole 13				Borehole 14				Borehole 15				Borehole 16				Borehole 17				Borehole 18				Borehole 19				Borehole 20
	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age	Thickness(m)	SPT-N	Soil Type	Soil Age
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40

V. Water Level (m):
VI. Initial Vertical Stress from Structure (kPa):

QUAKE-ADVICE

Program AU1 – AS1170.4 response spectrum generator