SOIL MECHANICS IIECV 3303

FACULTY OF ENGINEERINGCIVIL ENGINEERING DEPARTMENTECV 3303SOIL MECHANICS IISEMESTER 2 2013/2014

TITLE : COMPACTION TEST DATE OF PRACTICAL : 5 MARCH 2015GROUP NO. : 10NO.MATRIC NUNBERNAME

1.175360AHMAD ZAIM HARITH BIN BIBUDIN

2.174250MOHAMMAD NASRUL BIN CHE WAHAB

3.175710OSCAR CHIN CHEN HENG

4.174518MUHAMMAD SYAFIQ IKMAL BIN ABDUL WAHAB

5.176034WAN NURULHUDA HANIM BT WAN MOHAMAD

6.170422LIU JUNXIN

LECTURER : DR. HASLINDA BINTI NAHAZANANTEACHING ASSISTANT : MS. KIMBERLY ANAK JAYUMTECHNICIAN : EN. MOHD RAZALI ABDUL RAHMANDATE OF SUBMISSION : 12 MARCH 2015

Table of Contents

WORK OF SCHEDULE3INTRODUCTION4Figure 1 : Type of Soil Particles4OBJECTIVES5PROCEDURE6EQUIPMENT/APPARATUS9RESULT & CALCULATION11Table 111Table 211Graph 1 : Graph shows relationship betwwen dry density and moisture content14DISCUSSION15RECOMMENDATION16CONCLUSION17REFERENCES18APPENDICES19Figure 2 : Weighting the sample of compacted soil19Figure 3 : Putting the sample into the oven19Figure 4 : Compacted soil in a mould20Figure 5 : Stir the soil with water20Figure 6 : Soil is compacted21Figure 7 : Weighting compacted soil21

WORK OF SCHEDULEITEMSGROUP MEMBERS

NAMEMATRIC NO.

Front Cover, Table of Content, List of Figure, List of Table, Work of Schedule.Zaim Harith175360

Introduction, ObjectivesSyafiq Ikmal174518

Apparatus, MethodologyMohammad Nasrul174250

Result & CalculationHuda Hanim176034

Discussion, RecommendationOscar Chin175710

Appendices, Conclusion, ReferencesLiu Junxin170422

INTRODUCTIONSoil compaction occurs when soil particles are pressed together, reducing pore space between them (Figure 1). Heavily compacted soils contain few large pores and have a reduced rate of both water infiltration and drainage from the compacted layer. This occurs because large pores are the most effective in moving water through the soil when it is saturated. In addition, the exchange of gases slows down in compacted soils, causing an increase in the likelihood of aeration-related problems. Finally, while soil compaction increases soil strength-the ability of soil to resist being moved by an applied force-a compacted soil also means that roots must exert greater force to penetrate the compacted layer.Soil compaction changes pore space size, distribution, and soil strength. One way to quantify the change is by measuring the bulk density. As the pore space is decreased within a soil, the bulk density is increased. Soils with a higher percentage of clay and silt, which naturally have more pore space, have a lower bulk density than sandier soils.

Figure 1 : Type of Soil Particles

TheProctor compaction testis a laboratory method of experimentally determining the optimalmoisture contentat which a givensoiltype will become most dense and achieve its maximum drydensity. The term Proctor is in honor ofR. R. Proctor, who in 1933 showed that the dry density of a soil for a given compactive effort depends on the amount of water the soil contains duringsoil compaction.His original test is most commonly referred to as the standard Proctor compaction test; later on, his test was updated to create the modified Proctor compaction test.

OBJECTIVESThe objectives of this lab are ;1. To determine the optimal moisture content at which a given soil type will become most dense and achieve its maximum dry density.2. To demonstrate proctor method which is learned in the class.

PROCEDURENo.ProcedurePicture of the process

1.The soil sample is air dried and sieved through BS 20mm sieve. Gravel content in the sample is recorded.

2.3kg of the soil sample is weighed on the weighing machine.

3.210ml of water is added to the soil sample which is about 7% from its moisture content.

4.The mould and the base plate is weighed and labeled with M1

5.The soil was compacted inside the mould with 3 layers, with each layer was compacted using rammer with falling free height of 450mm for about 27 blows. The excess soil that protrude above the mould is removed to a level soil surface using metal edge.

6.The mould with the compacted soil is weighed and labeled with M2.

7.The sampling cans is weighed and labeled.

8.The compacted soil in the mould is removed and placed in the metal tray. Three different sample from the top, bottom and middle of the soil is taken for moisture content determination purposes and is placed in the sampling can.

9.The sampling can is weighed with the soil sample in it.

10.The remaining sample of the soil is added with 150ml of water which is about 5% of its moisture content. The test is repeated for 5 times.

11.The sampling can is oven dried for about 24 hours.

12.The oven dried sampling cans is weighed and the data is recorded.

EQUIPMENT/APPARATUSNo.EquipmentDescription

1.Cylindrical mould

Cylindrical mould of dimensions 105mm internal diameter, internal height 115.5mm, and volume 1000cm.

The mould is used to place the soil that will be compacted.

2.Rammer

The rammer of dimensions 50mm diameter, 4.5kg weight and free fall height of 450mm.

Rammer is used to compact the soil sample in the cylindrical mould.

3.Pallete knife

Pallete knife is used to mix the soil sample with water.

4.Metal tray

Metal tray is used to mix the soil with water.

5.Metal edge

Metal edge is used to remove excess soil that protrude above the mould. It is also used to level the soil samples surface.

6.Sampling can

Sampling can is used to place the soil sample to be oven dried.

7.Measuring cylinder

Measuring cylinder is used to measure the volume of water to be added to the soil.

RESULT & CALCULATIONTest No.12345

Weight of mould + moist soil, M2 (g)67576785686171257036

Weight of mould, M1 (g)51375137513751375137

Weight of moist soil, M2-M1 (g)16201648172419881899

Bulk density, (M2-M1)/1000 (Mg/m)1.621.651.721.991.90

Based on the experiment that has been implemented, we obtained the results as follow :

Container No.12345

Weight of moist soil + container (g)63.3366.0159.2666.5073.71

Weight of dry soil + container (g)60.1760.8953.5457.9462.63

Weight of container (g)14.4614.3713.7714.5314.10

Weight of dry soil (g)45.7146.5239.7743.4148.53

Weight of water (g)3.165.125.728.5611.08

Moisture content, w (%)711141923

1+w1.071.111.141.191.23

Dry density, = r/ (1+w) (Mg/m)1.511.481.511.671.54

Table 1

Table 2

1. The weight of mould + moist soil and the weight of mould itself are taken at the soil laboratory and from the reading, the weight of moist soil can be obtained where:Weight of moist soil = (Weight of mould + moist soil) (Weight of mould)2. From the value of the weight of moist soil, the bulk density can be obtained by using the formula below:Bulk density, = (Weight of mould + moist soil) (Weight of mould) / 10003. The moist soils are then being placed inside the oven for 24 hours in order to measure the water content inside the soils. The weights of water are obtained by subtracting the weight of moist soil + container and weight of dry soil + container. 4. Next, the percentages of the moisture content are calculated by dividing the weight of water and weight of dry soil and thus, the values of dry density may also be gained where;Dry density, = (Weight of mould + moist soil) (Weight of mould) 1000 (1+moisture content)5. The graph of moisture content versus dry density is then plotted in order to obtain maximum dry density and optimum moisture content. 6. The air void lines are plotted for three conditions which are 0%, 5% and 10%. 7. After getting the compaction curve as well as the air void lines, the values of maximum dry density and the optimum moisture content may be gained.

Table below depicts the values of the air void for the conditions of 0%, 5% and 10%. The calculation of the zero air void condition as well as 5% and 10% is getting by using the formula respectively:i. For zero air void condition

ii. For 5% and 10% air void condition

0% Air Void5% Air Void10% Air Void

2.272.162.04

2.081.981.87

1.961.861.76

1.781.751.61

1.671.581.5

Graph 1 : Graph shows relationship betwwen dry density and moisture contentHence;Gs: 2.7Maximum dry density: 1.67 Mg/mOptimum moisture content: 19%

DISCUSSIONIn this laboratory experiment, we were exposed to practical way of determining the relationship between dry density and moisture content for soil through soil compaction test. Firstly, data were obtained experimentally. Then, data are calculated and result is plotted into a graph. The graphs obtained were then compared to theoretical graph.Initially, the bulk density obtained show an increment as water content in the soil increased until test number 5 which show a slope downward. Meanwhile, after the dry density result is calculated and plotted on a graph, the result fluctuates at around 11% water content . Theoretically, it was supposed to be parabolic curve which open downward. This can be explained as water is added to a soil at low moisture contents, it becomes easier for the particles to move past one another during compaction. The soil were more compacted, the voids are reduced and this causes the dry density to increase. As the water content increases, the soil particles develop larger water films around them.This increase in dry density continues till a stage where water starts to occupy the space that could have been occupied by the soil grains. Thus the water at this stage hinders the closer packing of grains and reduces the dry unit weight. Themaximum dry density occurs at anoptimum water content,and their values can be obtained from the plot. The maximum dry density of 1.674 Mg/ can is obtained at optimum moisture content of 19%.The graph plotted is slightly incorrect as compared to theoretical graph. This might occur due to several errors. First each soil test with different water content is not compacted with the same strength. All members of our group take turns in doing the compaction for every different water content, this might cause the strength of compaction varies from one test to another. Secondly, it was raining during our experiment which is being carry out outside the laboratory. This can lead to a higher actual water content in our soil sample than we have recorded. Finally, the soil not being evenly compacted can also lead to a bias in the result.There are several precautionary steps that can be taken in order to improve the experiment. This experiment should be carry out inside the laboratory. Compaction should be done by only one member to ensure compaction strength is constant for each soil test.

RECOMMENDATIONThere are several precautionary steps that can be taken in order to improve the experiment. First of all, this experiment should be carry out inside the laboratory to avoid any effect that might occur due to the surrounding for instance weather.Next, compaction should be done by only one person to ensure that soil sample in each test is compacted with the same strength. Finally, the soil must be compacted evenly throughout the surface for a maximum compaction effect on the soil.

CONCLUSIONAs a conclusion, we managed to determine the air void in each percentage which is 0%, 5% and 10%. Besides that, we also managed to determine the Optimum Moisture Content of 16.35% with the calculated maximum dry density of 1.726Mg/m3. The compaction curve is for making the optimum density as close as the zero-air-void as possible on 5%. So, we able to have gone through this experiment successfully.

REFERENCES

Youventharan Duraisamy. 2009. Soil Mechaniccs Laboratory Manual. University Malaysia Pahang. Bujang B.K Huat. Faisal Hj. Ali. 1995. Essential Soil Mechanics. Universiti Putra Malaysia Press. Concrete-catalogue. Retrieved on October 21, 2011 from http://www.concrete-catalog.com/soil_compaction.html

APPENDICES

Figure 2 : Weighting the sample of compacted soil

Figure 3 : Putting the sample into the oven

Figure 4 : Compacted soil in a mould

Figure 5 : Stir the soil with water

Figure 6 : Soil is compacted

Figure 7 : Weighting compacted soil