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CE788: Geotechnical Engineering Testing (Spring 2015)

FINAL PROJECT REPORT

Submitted By

Al – Naddaf, Mahdi Abbas Mahdi

Jiang, Yan

Mohammed, Hemim Jalal

Neupane, Madan

Submitted to

Jie Han, Professor

Due Date 05/12/2015

Group 2: Final Project Work - Report

1

Table of Contents

Table of Contents ............................................................................................................................ 1

1. Acknowledgments ................................................................................................................... 6

2. Executive Summary ................................................................................................................. 6

3. Introduction ............................................................................................................................. 6

4. Physical Conditions ................................................................................................................. 8

3.1. Climate ............................................................................................................................. 8

3.2. Topography and Drainage ................................................................................................ 9

3.3. Regional Geology and Seismicity .................................................................................. 10

3.4. Soil Survey Mapping ...................................................................................................... 11

3.5. Sub-surface Conditions .................................................................................................. 13

5. Field Exploration ................................................................................................................... 14

4.1 Bore Hole Preparation .................................................................................................... 14

4.2 Drilling and Sampling .................................................................................................... 15

4.3 Standard Penetration Test (SPT) .................................................................................... 16

4.4 Vane Shear Test ............................................................................................................. 18

4.5 Pressure Meter Test ........................................................................................................ 18


2

4.6 Direct Push Bull Sampling ............................................................................................. 20

6. Laboratory Testing ................................................................................................................ 21

5.1 Specific Gravity Determination ..................................................................................... 21

5.2 Grain Size Distribution of Soil ....................................................................................... 21

5.3 Atterberg Limit Determination....................................................................................... 22

5.4 Consolidation of Sample ................................................................................................ 22

5.5 Unconfined Compression Test ....................................................................................... 24

5.6 Consolidated Undrained Test ......................................................................................... 25

7. Foundation Recommendations .............................................................................................. 28

6.1 Foundation Design Recommendation ............................................................................ 28

6.2 Foundation Construction Considerations ....................................................................... 30

8. Conclusions and comments ................................................................................................... 30

9. References ............................................................................................................................. 31

10. Appendix B: Boring log Sheet ........................................................................................... 37

11. Appendix C: Field Test Data Sheet ................................................................................... 39

12. Appendix D: Lab Test Data Sheet ..................................................................................... 43

13. Appendix F: The Calculation of Vertical Bearing Capacity of a Single Pile .................... 47


3

14. Appendix G: The Calculation of settlement of a Single Pile ............................................. 50

List of Tables

Table 3-1 Lawrence Climate. (Places, 2015) .............................................................................. 8

Table 3-2 Subsurface Conditions ............................................................................................... 13

Table 4-1 Location of Boreholes, Types of Digging and Activities Performed ..................... 15

Table 4-2 SPT Measured and Corrected N Values and Other Outcomes ............................. 17

Table 4-3 Vane Shear Test Results ............................................................................................ 18

Table 4-4 Result from Pressuremeter Test ............................................................................... 20

Table 5-1 Results from 1-D Consolidation Test ....................................................................... 22

Table 5-2 Results from CU Test ................................................................................................ 26

Table 6-1Recommended pile foundation .................................................................................. 28


4

List of Figures

Figure 3-1 Lawrence Climate (Places, 2015) .............................................................................. 9

Figure 3-2 Boreholes locations ................................................................................................... 10

Figure 3-3. Micro-earthquakes (*) and faults (/) in Kansas (Burchett, Luza, Van Eck, &

Wilson, 1983) ............................................................................................................................... 11

Figure 3-4. Pattern of Soils in Martin-Sogn-Vinland Association in Douglas County, KS

(Deckey, Zimmerman, Plinsky, & Davis, 1977) ....................................................................... 12

Figure 4-1: Test Site Location and Demarcation ..................................................................... 14

Figure 4-2: Drill Hole Preparation by Removing Top Paved Part ........................................ 15

Figure 4-3 Location of Shelby Tube Sampling ......................................................................... 16

Figure 4-4 Location of Standard Penetration Test at Different Boreholes ........................... 17

Figure 4-5 Volume and Pressure Calibration of Pressuremeter ............................................ 19

Figure 4-6 Corrected Pressuremeter Curve Showing Elastic Range and Plastic Range ..... 19

Figure 5-1 Gradation Curve of the Sampled Soil .................................................................... 21

Figure 5-2 Void Ratio versus Pressure Curve (Log Scale) ...................................................... 23

Figure 5-3 Taylor`s root time method ....................................................................................... 23


5

Figure 5-4 Casagrande's log t Method ...................................................................................... 24

Figure 5-5 Stress versus Strain Curve of Unconfined Compression Test.............................. 25

Figure 5-6 Deviator Stress versus Strain Curve of CU Test ................................................... 26

Figure 5-7 Normal Stress versus Axial Strain Curve .............................................................. 27

Figure 5-8 Mohr Column Failure Envelope ............................................................................. 27

Figure 6-1 Soil profile for the design of the piled foundation ................................................. 29

Figure 9-1. KU Central District Plan (dcm.ku.edu) ................................................................ 33

Figure 9-2. Site Location Plan.................................................................................................... 35

Figure 9-3. Borings Location plan ............................................................................................. 35

Figure 9-4. Topography map of Test Location (3) ................................................................... 36

Figure 10-1. Subsurface Exploration and Sampling Sheet (˂19 feet depth) ......................... 37

Figure 10-2. Subsurface Exploration and Sampling Sheet (>19 feet depth) ......................... 38


6

1. Acknowledgments

Thanks to Kansas department of transportation (KDOT) for providing the necessary equipment

for the tests were conducted for this report. Thanks to CEAE department also for the facilities

they provided for this report.

2. Executive Summary

A geotechnical investigation has been conducted for a two-storey building close to Burge Union.

Based on the information from the subsurface exploration, field in-situ tests, and lab tests, the

following geotechnical summaries were given:

From the field test, the undrained shear strength of the foundation soil was very high. The

undrained shear strength were an average of 72 kPa from SPT test, 92.4 kPa from Vane shear

test (undisturbed) and 71 kPa from pressruemeter test.

This result was supported by the laboratory test as the unconfined compressive gives the

undrained shear strength of 94.8 kPa. So, the foundation is strong enough to support probable

foundation. Also, from consolidation test, it was found that the filed was over consolidated. Also,

the permeability of the soil is very small.

3. Introduction

This report presents the results of the subsurface exploration and geotechnical engineering

services performed for a new construction planned to be located at the Child Care Drive, west of

Burge Union, at the campus of University of Kansas (KU), Lawrence, Kansas, as shown in


7

Appendix A-Figure 7 and Figure 8. The purpose of these exploration and geotechnical

engineering services is to provide information and geotechnical engineering recommendations

relative to:

Subsurface soil conditions

Groundwater conditions

Foundation design and construction

Estimated seismic site class

Earthwork

Construction considerations

Lateral earth pressures

The geotechnical scope of work for this project included the advancement of five boreholes,

only three of them were conducted to a depth about 17½ ft below the existing grade in the area of

the proposed new construction, as shown in Appendix A-Figure 9 The boreholes were conducted

by a geotechnical group of KDOT using their advanced equipment for testing and analyzing a

geotechnical characteristics of the soil at that location.

In this context, the graduate students at CE 788 class in the school of engineering at KU

conducted a laboratory tests on the Shelby tube samples were extracted from the boreholes. The

students were divided into three groups. Group 2 performed four types of geotechnical tests:

Atterberg limit test, hydrometer test, one dimensional consolidation test, and Consolidation

undrained triaxial test on the samples were pulled out from the borehole number 4 by Shelby

tube number 2 and 5.


8

4. Physical Conditions

3.1. Climate

The climate of Lawrence, where the exploration and geotechnical engineering services were

conducted, gets more than 39 inches of rain per year, while the US average is 37 (Data, n.d.).

Snowfall is 13 inches, while the average US city gets 25 inches of snow per year, as shown in the

Table 1 and Figure 1.

On average, there are 211 sunny days per year in Lawrence. The highest temperature in

July is around 90 degrees. The January low is 18. Comfort index, which is based on humidity

during the hot months, is a 30 out of 100, where higher is more comfortable. The US average on

the comfort index is 44 (Places, 2015).

Table 4-1 Lawrence Climate. (Places, 2015)

Climate\Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual

Avg.

Average high

(°F) 38 44 55 65 74 83 89 88 79 67 54 41 64.8

Average

low (°F) 18 22 31 43 54 64 68 66 57 45 33 22 43.6

Avg.

Precipitation

(inch)

1 1.4 2.7 4.1 5.4 5.9 4.1 4.1 4.2 3.4 2.2 1.6 39.92

Average

snowfall (inch) 4 4 1 0 0 0 0 0 0 0 1 3 13


9

Figure 4-1 Lawrence Climate (Places, 2015)

3.2. Topography and Drainage

The test location is located at 880 to 890 ft above sea level (pickatrail, n.d.), as shown in

Appendix A-Figure 10. The area, where the borings were conducted, was almost level. The

borings were in the park lot, which is paved by a 5.75 inches flexible pavement, as shown in

Figure 2. The boring area has a good drainage through the drain pipes were transfer the rainfall

water to the nearby opened drain channel.


10

Figure 4-2 Boreholes locations

3.3. Regional Geology and Seismicity

The most seismic activate area in Kansas is along and parallel to the Humboldt fault zone. In the

northern part of this zone, micro–earthquakes and felt earthquakes near Manhattan are associated

with the Humboldt zone itself. The second most active area is a northeast-southeast-trending

zone near the Nebraska border in Washington, Republic, and cloud Counties, as shown in Figure

3 (Burchett, Luza, Van Eck, & Wilson, 1983). The largest earthquake in Kansas was Manhattan

earthquake, which was happened in April 24, 1867 Measuring 5.1 on the Richter scale. This

earthquake caused several minor injuries, cracked walls, and loosened stones from buildings. At

Manhattan, a 0.6-meter wave was seen moving south to north on the Kansas River (USGS, n.d.).


11

Figure 4-3. Micro-earthquakes (*) and faults (/) in Kansas (Burchett, Luza, Van Eck, &

Wilson, 1983)

3.4. Soil Survey Mapping

The soil survey was conducted on Douglas County, which contained required information to

manage farms, ranches, and woodlands and to select sites for roads, ponds, building, and other

structures to find out the suitability of tracts of land for farming, industry, and recreation as well.

The survey distributed the soil in Douglas County into five associations (Deckey,

Zimmerman, Plinsky, & Davis, 1977):


12

Martin-Sogn-Vinland Association, which make up about 48 percent of the County and

includes Martin soil about 35 percent, Sogn soil 18 percent, Vinland soil 14 percent, the

remaining is minor soils, as shown in Figure 4.

Figure 4-4. Pattern of Soils in Martin-Sogn-Vinland Association in Douglas County, KS

(Deckey, Zimmerman, Plinsky, & Davis, 1977)

Wabash-Kennebec-Reading Association, which makes up about 12 percent of the

County.

Pawnee-Woodson-Morrill Association makes up about 9 percent of the County.

Sibleyville-Martin-Woodson Association makes up 24 percent of the County.

Eudora-Kimo Association makes up 7 percent of the County.


13

For dwelling and small commercial buildings, the survey recommend to build structures with

a foundation loads have a foundation load not more than three stories high on undisturbed soil.

For such structures, soil should be sufficiently stable that neither cracking (or subsidence from

settling) nor shear failure of the foundation occur. Soil wetness and depth to a seasonal high

water table indicate potential difficulty in providing accurate drainage for basements and gardens

(Deckey, Zimmerman, Plinsky, & Davis, 1977).

3.5. Sub-surface Conditions

Subsurface exploration and sampling at the boring locations are indicated on Appendix B

Stratification boundaries on the boring log in the data sheet represent the approximate location of

changes in material types. The transition between materials may be gradual or abrupt

horizontally and vertically in-situ. Based on the results of the boreholes, subsurface conditions of

the project site can be generalized, as shown in the Table 2. After fourth stratum the hard layer of

soil was encountered. Therefore, bottom of boring at 26.7 feet refused.

Table 4-2 Subsurface Conditions

Stratum

Thickness

of Stratum

(feet)

Material Description Moisture Density

Surficial 0.6 Asphalt Pavement N/A N/A

1st Stratum 2.4 Dark brown and gray clay Very moist Stiff

2nd Stratum 13.5 Brown clay Moist, less moist

with depth Stiff

3rd Stratum 8.2 Brown clay Slightly moist Stiff

4th Stratum 2 Light brown clayey silt Dry Firm


14

5. Field Exploration

4.1 Bore Hole Preparation

KDOT’s geotechnical engineering crew demarked the investigation site. KU is going to

construct a new Integrated Science buildings and landscaping in the area. The KDOT crew

prepared five holes by demarking almost in the straight line. The Test location and demarcations

are shown Figure 5.1.

Figure 5-1: Test Site Location and Demarcation

KDOT crew used a pavement cutter to remove the top of the paved parking lot at site. The cutter

size was 10 inches diameter. The borehole prepared after removing the surface paved part is

shown in Figure 5.2.

Hole

Hole

Hole 3

Hole 2

Hole 1


15

Figure 5-2: Drill Hole Preparation by Removing Top Paved Part

4.2 Drilling and Sampling

KDOT crew used hollow flying augur and solid flying augur depending upon the necessities of

the test on the particular borehole – that were previously planned. Table 5.1 demonstrates the

types of test or sampling performed in each boreholes and method of digging of holes.

Table 5-1 Location of Boreholes, Types of Digging and Activities Performed

Location Borehole Method Activities performed

Borehole 1 Hollow flying augur

Shelby tube sampling

SPT test

Vane shear test

Disturbed sample collection for lab tests

Borehole 2 Solid flying augur Pressure meter test

Demonstration of borehole shear test

Borehole 3 Bull sampling Bull sampling

Borehole 4 Hollow flying augur SPT

Shelby tube

Borehole 5 Hollow flying augur Shelby tube

The undisturbed sampling was carried out by 3.5 inch diameter and 30 inch long Shelby tube.

The Shelby tube was penetrated at the required depth as mentioned in Figure 4.3. Altogether 6


16

sampling were carried out in Shelby tube. The locations (depth and area) of the Shelby tubes

sampling are given in Figure 5.3 and Figure 5.1.

Figure 5-3 Location of Shelby Tube Sampling

Some photographs regarding the boring and sampling are presented in Appendix C.

4.3 Standard Penetration Test (SPT)

Standard Penetration Test was carried out at borehole 1 and borehole 4 by inserting 2 inch

diameter split-spoon sampler at the different depth. The location of the SPT tests are shown in

Figure 5.4.

Borehole 1 Borehole 4 Borehole 5

7-8.5 ft

16-17.5 ft

Shelby tube 1 Shelby

tube 2

Shelby

tube 3

Shelby

tube 4

Shelby

tube 5 Shelby

tube 6

4.5-6.3 ft

ft


17

Figure 5-4 Location of Standard Penetration Test at Different Boreholes

The measured SPT N value at SPT 1 (borehole 1) was 11, SPT 2 was 13 and SPT 3 was 11. The

measured N values at the SPT test and the corresponding outcomes of the test are presented in

Table 4.2. The calculations for the outcomes are presented in Appendix C.

Table 5-2 SPT Measured and Corrected N Values and Other Outcomes

Location Measured N

Value

Corrected N60

Value

N160 Su (kPa)

(Terzaghi)

Su (kPa)

(Hara)

SPT 1 (Borehole1) 11 16 32 66 163

SPT 2 (Borehole

2)

13 21 28 78 183.8

SPT 3 (Borehole

2)

11 20 22 66 163

The Su is almost constant throughout the soil layer. Also, the measured N values are pretty

constant in all measured depth.

Borehole 1 Borehole 4

9.0-10.5

18-19.5ft

SPT 1

SPT 2

SPT 3

3.0-4.5 ft

ft


18

4.4 Vane Shear Test

The KDOT crew conducted vane shear test at borehole 1 at the depth of 9 ft by using 2 inch

diameter tapered vane shear apparatus due to stiffer nature of the clay soil at site. The torque arm

length of the vane shear apparatus was 12 inches and the vane shear constant of 5.17. The critical

(failure state) field data and the results are presented in Table 4.3

Table 5-3 Vane Shear Test Results

Conditions Failure State applied

force (lbf)

Undrained shear

strength (kPa) Soil Sensitivity

Undisturbed 45 92.44 Insensitive

Remolded 39 80.11

The detail calculation of the test results are given in Appendix C and corresponding photographs

to vane shear test are given in Appendix C.

4.5 Pressure Meter Test

Pressure meter test was carried out at borehole 2 at the depth of 8.0 feet based on ASTM 4719. A

borehole was drilled with solid continuous auger having 3 inches. The diameter of the

pressuremeter probe was 66 mm (2.6 inches).

KDOT engineers carried out the calibration of the pressurementer at KDOT lab. Based on the

provided data, the calibration curves are presented in Figure 4.5


19

Figure 5-5 Volume and Pressure Calibration of Pressuremeter

Based on the corrected pressuremeter data, the corrected pressuremeter curve is plotted in Figure

5.6.

Figure 5-6 Corrected Pressuremeter Curve Showing Elastic Range and Plastic Range

0

100

200

300

400

500

600

700

0 0.5 1 1.5 2 2.5 3 3.5

volu

me

(cm

3)

pressure (bar)

Volume calibration curve Pressure calibration curve

0

1

2

3

4

5

6

0 100 200 300 400 500 600 700 800 900 1000

Co

rrec

ted

pre

ssu

re (

bar

)

Corrected volume (cm3)


20

Group B interpreted the following results from this test:

Table 5-4 Result from Pressuremeter Test

Name of Test Lateral Earth

Pressure Coff. at

Rest (K0)

Pressuremeter

Elastic Modulus

(EPMT) kPa

Udrained shear

strength (Su)

kPa

Preconsoilidation

Stress (σ’p) kPa

Pressuremeter 1.1 3691.0 71.0 230.4

The more photographs about the pressuremeter test are presented in Appendix D.

4.6 Direct Push Bull Sampling

Sampling was carried out by direct push bull sampling and analyzed by inspection. A field log

sheet was filled by inspecting the data for classification and characterization of soil. The log

sheet obtained from the bull sampling is presented in Appendix C and the photographs related to

the bull sampling is given in Appendix D.


21

6. Laboratory Testing

5.1 Specific Gravity Determination

Group two tested the specific gravity of the sample following by ASTM D854 - 14. We took this

sample from Shelby tube. The sample contains all particles less than sieve size 4 and more

specifically almost all clay particles. Group two found the specific gravity of 2.69 for the

sampled soil. Calculation is presented in Appendix D.

5.2 Grain Size Distribution of Soil

Group 2 conducted the standard test for particle size analysis of fine soil based on D422 – 63.

From this laboratory test, we found 6.3% of particle retained on sieve size 200 ( <15%). The

particle size distribution graph is in Figure 5.1. We found that coefficient of uniformity (Cu) and

coefficient of curvature (Cc) are 10 and 0.63 respectively.

Figure 6-1 Gradation Curve of the Sampled Soil

0.0%

20.0%

40.0%

60.0%

80.0%

100.0%

0.001 0.010 0.100 1.000

% p

assi

ng

Diamter in mm


22

5.3 Atterberg Limit Determination

We determined the plastic limit and liquid limit based on D4318 - 10. The sampled soil have the

plastic limit of 24 and the liquid limit of 54. The plasticity index is 30. We found that the soil fall

above A-Line in the plasticity chart. And the soil is considered to be CH soil from USCS

classification. The laboratory data sheet for the Atterberg limit calculation are presented in

Appnendix D.

5.4 Consolidation of Sample

Group two performed the 1-D Consolidation Test based on ASTM D2435-96 at civil engineering

lab at KU. This sample was taken from the top part of the Selby tube no 2. The initial void rato

of the sample was 0.64. The overconsolidation (OCR) of the sample was 3.3. The coefficient of

consolidation was found as 0.021 cm2/min from Taylor’s Square Root Method. Also, we

calculated recompression index (Cr) of 0.0316 and compression index (Cc) of 0.082. The results

obtained from 1-D consolidation test are given in Table 5.1:

Table 6-1 Results from 1-D Consolidation Test

Preconsolidation

stress (σp’)

D’ (MPa) Cv by

Casagrande’s

Method

Cv by Taylor’s

Square root

method

K by

Casagrande's

kPa MPa cm2/min cm2/min cm/min

150 12.615 0.01 0.018 7.776 x 10-8

Group 2 select the Casagrande’s Method to calculate the permeability since Cv of Casagrande’s

method was lower as compared to Taylor’s method. The applied pressure versus void ratio curve,

Taylor’s square root method and Casagrande’s log t method are presented in Figure 5.2, Figure

5.3 and Figure 5.4 respectively.


23

Figure 6-2 Void Ratio versus Pressure Curve (Log Scale)

Figure 6-3 Taylor`s root time method

0.5400

0.5600

0.5800

0.6000

0.6200

0.6400

0.6600

0.1 1 10 100 1000

Vo

id r

atio

, e

Pressure, p (kPa)

0.045

0.049

0.053

0.057

0.061

0.065

0 5 10 15 20 25 30 35 40

Dia

l rea

din

g (i

n)

Square root time

t50


24

Figure 6-4 Casagrande's log t Method

5.5 Unconfined Compression Test

This unconfined compression test was carried out by Zachary Aaron Brady (TA) for

undergraduate class and he provided the data of this test. The unconfined compression stress

versus the axial strain graph is shown in Figure 6.6. The sample failed at 27.5 psi (189.6 kPa).

0.045

0.049

0.053

0.057

0.061

0.065

0.1 1 10 100 1000

Dia

l Rea

din

g (i

n)

Time, (min)t90


25

Figure 6-5 Stress versus Strain Curve of Unconfined Compression Test

The undrained shear strength is evaluated as 13.75 psi (94.8 kPa).

5.6 Consolidated Undrained Test

The consolidated undrained triaxial test was carried out from Shelby tube 2 of borehole 4. The

sample was extracted by vertical extractor at geotechnical laboratory at KU. Then the sample

was cut in average of 2.8 inches diameter and almost 5.8 inches height. The exact dimensions of

the sample before placing the triaxial set were 7.2cm (2.836 inches) diameter and 14.92 cm

(5.876 inches) height. The field unit weight of the sample was 19.5 kN/m3.

The sample was left for saturation under cell pressure of 448 kPa (65 psi), the inlet back pressure

of 427 kPa (62 psi) and outlet pressure of 414 kPa (60 psi). After saturation, we allowed the

sample for consolidation for 48 hours with cell pressure of 522 kPa (75.7 psi) and back pressure

of 425 kPa (61.7 psi). After 48 hours of consolidation, the sample was assumed to be

consolidated perfectly. Then the sample was sheared. The deviator stress versus strain curve,

normal stress versus strain curve and Mohr Column failure envelope are presented in Figure 5.8 .

0

5

10

15

20

25

30

0 1 2 3 4 5 6 7

Un

con

fin

ed c

om

pre

ssio

n s

tres

s, p

si

Axial Strain, %

Stress strain curve for unconfined compression test


26

The sample was considered to be failure at 10% strain and the corresponding deviator stress is

292 kPa (42.4 psi). The results at failure (10% strain) are presented in Table 5.2

Table 6-2 Results from CU Test

Group No Deviator

pressure

Confining

Pressure

Pore Water

Pressure

Effective

confining pressure

Effective

Normal Pressure

kPa kPa kPa kPa kPa

Group 1 5225.6 50 101.6 -51.6 173.9

Group 2 292.1 96.5 72.7 23.8 316

Figure 6-6 Deviator Stress versus Strain Curve of CU Test

0

10

20

30

40

50

0 2 4 6 8 10 12 14

Dev

iato

r st

ress

, (p

si)

Axial strain, (%)


27

Figure 6-7 Normal Stress versus Axial Strain Curve

Figure 6-8 Mohr Column Failure Envelope

0

10

20

30

40

50

60

70

0 2 4 6 8 10 12 14

Tota

l an

d E

ffec

tive

no

rmal

str

ess,

(p

si)

Axial strain, %

Total stress Effective stress

0

5

10

15

20

25

30

-10 0 10 20 30 40 50 60

Dev

iato

r st

ress

, (p

si)

Stress, (psi)

Group 2 - Total Stress Mohr Circle Group 2 - Effective Stress Mohr Circle

Group 1 - Total Stress Mohr Circle Group 1 - Effective Stress Mohr Circle

Total Stress Failure Envelope Effective Stress Failure Envelope


28

7. Foundation Recommendations

In order to meet the performance requirement of superstructures, it was recommended that the

superstructures should be constructed on a sufficient foundation. Shallow foundations and pile

foundations were considered and compared. Based on the load of superstructure and the soil

properties provided from the above geotechnical investigation, a piled foundation is recommended

to support superstructures. The detailed information is provided in Table 6.1.

6.1 Foundation Design Recommendation

Table 7-1Recommended pile foundation

Description Value

Structures Two-storey building as an extension of Burge Union

Foundation types Piled foundation

The vertical bearing capacity of

the single pile

2319 kN

Total estimated settlement 7.5 mm

Note: 1. a 30-kPa design load for two-storey building was assumed and a 5-m center to center spacing of columns in

horizontal directions was assumed as well. A 750-kN load was transferred to the top of the single pile from the column

when the single pile supported the column.

In the calculation of the vertical bearing capacity of the single pile and the settlement, there were

five soil layers along the length of the pile. These soil layers were determined according to the

visual observation. The corresponding soil properties were measured from in-situ tests and lab

tests. A 15-m long pile with the diameter of 1 m was used to support one column. Since the pile

toe is in the firm clay, the pile is considered to be end-bearing pile.

In addition, the short term is the control condition because the pile penetrated into the clay

layers. The vertical bearing capacity of the single pile uses α method to consider the short term

bearing capacity. The factor of safety for bearing capacity was set to be 3. The piles are cast in-


29

situ concrete piles. Since the superstructure is two-storey building, the bearing capacity under the

lateral loading was not concerned. The calculation of the settlement of the pile used Randolph and

Wroth (1978)’s method. The considerations of soil parameters and the detailed calculation of the

vertical bearing capacity of a single pile is shown in Appendix F. The consideration of soil

parameters and the detailed calculation of the settlement can be seen in Appendix G.

Figure 7-1 Soil profile for the design of the piled foundation

The vertical bearing capacity of the single pile and its settlement are up to the uncertain conditions,

such as the subsurface profile, the structural conditions, and the quality of construction operations.

Piled foundations under these variable conditions could experience less vertical bearing capacity

and greater total and differential settlement than estimated and may not be predictable. The field

monitoring is recommended to guarantee the predicted results are sufficiently accurate.


30

6.2 Foundation Construction Considerations

The cast in-situ concrete piles will be installed into the soil. The soil properties may change due

to the disturbance resulting from boring. The disturbed soil may reduce the vertical bearing

capacity of the single pile and increase the settlement.

In addition, the pile integrity tests are suggested to check the quality of installed piles. A pile cap

has to be cast in situ on the top of the pile to connect a column.

8. Conclusions and comments

From the field test, the undrained shear strength of the foundation soil was very high. The

undrained shear strength were an average of 72 kPa from SPT test, 92.4 kPa from Vane shear test

(undisturbed) and 71 kPa from pressruemeter test.

This result was supported by the laboratory test as the unconfined compressive gives the undrained

shear strength of 94.8 kPa. So, the foundation is strong enough to support probable foundation.

Also, from consolidation test, it was found that the filed was over consolidated. Also, the

permeability of the soil is very small.

The piled foundation is recommended to support the two-storey building. The calculated vertical

bearing capacity and the settlement of the single pile were 2391 kN and 7.5 mm, respectively. The

calculated vertical bearing capacity of the single pile may reduce and the settlement of the single

pile may increase due to variation of the subsurface profile, the structural conditions, and the

quality of construction operations.


31

9. References

Burchett, R. R., Luza, K. V., Van Eck, O. J., & Wilson, F. W. (1983). Seismicity and tectonic

relationships of the Nemaha Uplift and Midcontinent geophysical anomaly. Final project

summary. Lincoln,Norman,Iowa city, Lawrence: Nebraska University ; Oklahoma

Geological Survey; Iowa Geological Survey; Kansas Geological Survey.

Data, U. C. (n.d.). Climate Lawrence - Kansas. Retrieved 05 09, 2015, from

http://www.usclimatedata.com/:

http://www.usclimatedata.com/climate/lawrence/kansas/united-states/usks0319

Deckey, H. P., Zimmerman, J. L., Plinsky, R. O., & Davis, R. D. (1977). Soil Survey of Douglas

County. Kansas.

pickatrail. (n.d.). Lawrence East, Kansas 7.5 Minute Topo Map. Retrieved 05 09, 2015, from

http://www.pickatrail.com/: http://www.pickatrail.com/topo-map/l/7.5x7.5/lawrence-east-

ks.html

Places, S. B. (2015, 05 08). Climate in Lawrence, Kansas. Retrieved from

http://www.bestplaces.net/: http://www.bestplaces.net/climate/city/kansas/lawrence

USGS. (n.d.). Kansas Earthquake Information. Retrieved 05 09, 2015, from

earthquake.usgs.gov/: http://earthquake.usgs.gov/earthquakes/states/?region=Kansas

Appendix A: Filed exploration

Figure 9-1. KU Central District Plan (dcm.ku.edu)

New Construction


34

Test Location


35

Figure 9-2. Site Location Plan

Figure 9-3. Borings Location plan

Boring 1

Boring 5

Boring 4

Boring 3

Boring 2


36

Figure 9-4. Topography map of Test Location (3)

Test Location


37

10. Appendix B: Boring log Sheet

Figure 10-1. Subsurface Exploration and Sampling Sheet (˂19 feet depth)


38

Figure 10-2. Subsurface Exploration and Sampling Sheet (>19 feet depth)


39

11. Appendix C: Field Test Data Sheet


40


41


42


43

12. Appendix D: Lab Test Data Sheet

Appendix D: Field Moisture Content Determination

Nos of Sample

Container Name

Empty Wt. of Container

Container + Wet Weight

of Soil

Container + Dry Weight

of Soil

Moisture Content of

Smaple

1 1 32.71 66.49 59.89 0.242826

2 L3AJ 29.52 66.16 58.98 0.24372

Average MC 24.3%

Appendix D: Specific Gravity Test Data

Wt. of empty

flask wt. of

flask+Water wt. of

flask+water+soil Mass of dry

soil Temperature

gm gm gm Degree C

174.06 672.31 706.27 54.06 26

Appendix D: Liquid Limit Determination

No. of blow

Can Identification

Empty wt. of Can

Can + Moist Soil Wt.

Can+ Dry soil Wt.

MC

45

Hall 17.13 32.75 27.5 50.6%

50.3% 10 15.92 30.89 25.9 50.0%

38

EAGS 15.54 22.69 20.3 50.2%

51.5% 8 15.96 23.51 20.9 52.8%

26

M42 15.48 30.01 24.9 54.2%

54.0% I# 16.16 32.05 26.5 53.7%

19

CBM2 21.5 37.5 32 52.4%

53.0% DM41 22.22 31.1 28 53.6%

16

16.26 34.99 28.1 58.2%

58.2% mv1 16.2 37.24 29.5 58.2%

So, from graph, liquid limit is 54


44

Appendix D: Plastic Limit Determination

Can Identification Empty wt.

of Can Can + Moist

Soil Wt. Can+ Dry soil Wt.

MC Average MC

E12 9.9 11 10.79 0.235955 24.3% FR13 9.9 11.2 10.94 0.25

Appendix D

Gradation by Hydrometer Analysis

General Data

Tested By: Group 2 Moisture content Date: 4/27/2015 M of Container 0 gm

Mass of air dry, M

Mass of Soil + Container - Wet 50

Specific Gravity, Gs 2.69

Mass of Soil + Container - Dry 0

Hydrometer: 152H Dry mass of Soil 0 Meniscus correction,

Fm 0.5 w 0.00% mass of

soilds, Ms 50 Dry mass of soil 50 g

α correction: 1.005 gm

Time,

T(min) Zero

Correction Hydrometer

Reading Corrected Reading

% Finer K

Diameter (mm)

93.7% 0.075

27.6 0.5 7 51 44.5 89.4% 0.0127 0.050

27.6 1 7 48 41.5 83.4% 0.0127 0.037

27.6 2 7 44 37.5 75.4% 0.0127 0.027

27.6 4 7 42 35.5 71.4% 0.0127 0.019

27.6 8 7 40 33.5 67.3% 0.0127 0.014

27.6 15 7 32 25.5 51.3% 0.0127 0.011

27.6 30 7 30 23.5 47.2% 0.0127 0.008

27.6 60 7 27.5 21 42.2% 0.0127 0.006

27.6 120 7 24 17.5 35.2% 0.0127 0.004

28 240 7 21 14.5 29.1% 0.0126 0.003

27.5 480 7 16 9.5 19.1% 0.0127 0.002

27.5 720 7 14 7.5 15.1% 0.0127 0.002

27.5 1440 7 11.5 5 10.1% 0.0127 0.001


45

Appendix D: Consolidation Test Data Sheet and Calculation

time

(min) Accumulative

time (min) time root

Loading (kg) kg

Pressure (kPa)

dial reading

dial reading (in)

0 0 0.00 0 0 0.00 23.60 0.2360

1440 1440 0.00 1 10 31.31 23.09 0.2309

0.1 1440.1 0.32 2 20 62.62 22.98 0.2298

0.25 1440.35 0.50 2 20 62.62 22.97 0.2297

0.5 1440.85 0.71 2 20 62.62 22.96 0.2296

1 1441.85 1.00 2 20 62.62 22.95 0.2295

2 1443.85 1.41 2 20 62.62 22.95 0.2295

4 1447.85 2.00 2 20 62.62 22.94 0.2294

8 1455.85 2.83 2 20 62.62 22.93 0.2293

15 1470.85 3.87 2 20 62.62 22.93 0.2293

30 1500.85 5.48 2 20 62.62 22.92 0.2292

60 1560.85 7.75 2 20 62.62 22.92 0.2292

120 1680.85 10.95 2 20 62.62 22.91 0.2291

240 1920.85 15.49 2 20 62.62 22.90 0.2290

480 2400.85 21.91 2 20 62.62 22.89 0.2289

1440 3840.85 37.95 2 20 62.62 22.88 0.2288

1440 5280.85 0.00 4 40 125.25 22.33 0.2233

1440 6720.85 0.00 8 80 250.49 21.21 0.2121

1440 8160.85 0.00 16 160 500.99 19.57 0.1957

0.1 8160.95 0.32 32 320 1001.98 18.81 0.1881

0.25 8161.2 0.50 32 320 1001.98 18.77 0.1877

0.5 8161.7 0.71 32 320 1001.98 18.72 0.1872

1 8162.7 1.00 32 320 1001.98 18.67 0.1867

2 8164.7 1.41 32 320 1001.98 18.60 0.1860

4 8168.7 2.00 32 320 1001.98 18.52 0.1852

8 8176.7 2.83 32 320 1001.98 18.41 0.1841

15 8191.7 3.87 32 320 1001.98 18.28 0.1828

30 8221.7 5.48 32 320 1001.98 18.10 0.1810

60 8281.7 7.75 32 320 1001.98 17.91 0.1791

120 8401.7 10.95 32 320 1001.98 17.74 0.1774

240 8641.7 15.49 32 320 1001.98 17.61 0.1761

480 9121.7 21.91 32 320 1001.98 17.55 0.1755

1440 10561.7 37.95 32 320 1001.98 17.49 0.1749

1440 12001.7 0.00 8 80 250.49 18.66 0.1866

1440 13441.7 0.00 2 20 62.62 20.21 0.2021


46

Appendix D: Consolidation Test Calculation


47


48


49

13. Appendix F: The Calculation of Vertical Bearing Capacity of a Single

Pile

The short term is the control condition for vertical bearing capacity of the single pile in this project.

Therefore the undrained condition (i.e., α method is used for friction resistance) was used to

calculate the vertical bearing capacity of the single pile. The undrained shear strengths of soils

were calculated from the results of SPT, the vane shear tests, the unconfined compression tests,

and the pressure meter tests. The undrained shear strengths of soils from the results of SPT were

selected to yield a conservative design. The properties of soils for the calculation of vertical

bearing capacity of the single pile are summarized in Table F.1.

Table F.1 the properties of soils

Layer Soil Top (ft) Bottom (ft) Thickness (m) Undrained shear strength (kPa)

1 Dark brown and gray clay 0.5 3.8 0.99 66

2 Brownish gray clay 3.8 8.2 1.32 66

3 Dark reddish brown clay 8.2 15.3 2.13 78

4 Brown clay, slightly moist 15.3 24.7 2.82 66

5 Light brown clayey silt 24.7 50.5 7.74 66

The values of α were calculated based on API method. The equations of calculation were given

in the following:

(Equation F.1)


48

The α values, friction resistance, and friction bearing load are summarized in Table F.2.

Table F.2 the calculated results for side bearing load

Layer Soil α Friction resistance, fs (kPa) Frinction bearing load (kN)

1 Dark brown and gray clay 0.59 38.94 121.1

2 Brownish gray clay 0.59 38.94 161.5

3 Dark reddish brown clay 0.5 39 261.0

4 Brown clay, slightly moist 0.59 38.94 345.0

5 Light brown clayey silt 0.59 38.94 946.9

The toe resistance was calculated based on the following Equation (F.2):

(Equation F.2)

The bearing capacity of the single pile is the sum of friction bearing capacity and toe bearing

capacity.

ts QQQ (Equation F.3)

The allowable load applied on the top of pile is

FS

QQallowable (Equation F.4)

Calculation example:

1. Friction bearing capacity (α method):

For Layer 1, the soil is Dark brown and gray clay. Its undrained shear strength is 66 kPa,

which is less than 75 kPa but greater than 25 kPa.

59.050/25665.0150/255.01 us

9.386659.0 us sf kPa

1.12199.019.38 sss AfQ kN


49

2. Toe bearing capacity

8.6156633.9* uct sNq kPa

6.48314

14.38.615 2 ttt AqQ kN

3. The vertical bearing capacity of a single pile

23196.4834.1835 ts QQQ kN

4. The allowable load applied on the top of pile

7733

2319

FS

QQallowable kN>750 kN

14. Appendix G: The Calculation of settlement of a Single Pile

The calculation of settlement of a single pile used Randolph and Wroth (1978)’s method.

dE

PI

D

(Equation G.1)

Where P is the axial load at the top of the pile, I is the influence factor, DE is the soil

modulus at the toe, and d is the diameter of the pile.

The axial load transfers to the top of pile 750P kN, and the diameter of pile 1d m. The

moduli of soils for different layers were estimated using the results from triaxial tests, one-

dimensional consolidation tests, vane shear tests, and pressure meter tests. The comparison of

these results was conducted to determine the design value used in the calculation. The moduli of

clays at the pile toe and below the pile toe were 10 MPa (i.e., 10DE MPa, 10bE MPa). The

average modulus of clays was also 10 MPa (i.e., 10avgE MPa). Poisson’s ratio of clays were 0.3.

In addition, the modulus of the pile was 30 GPa.

Calculation example:

The pile length, 15D m

11

1

d

db

110

10

b

D

E

E


51

110

10

D

avg

E

E

780010

300003.01212

D

p

sE

E

96.3)}1

152](1)25.0)3.01(15.2(25.0ln{[

)}2

]()25.0)1(5.2(25.0ln{[

d

Ds

24.01

15

780096.3

22

22

d

DD

1.0

}1

15

24.0

24.0tanh

96.3

114.34

1

1

3.01

4{

}1

15

24.0

24.0tanh

1

1

3.01

8

780014.3

11{

3.014

}tanh4

1

4{

}tanh

1

811{

14

d

D

D

D

d

D

D

D

I

s

ss

5.7110

1.0750

dE

PI

D

mm

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