The Effect of Soaking on CBR Values in Soft Soils Stabilized with Stone Ash and Sand

Constructing in the soft soil is necessary to improve. The improvement of soft soil by mixing natural materials, namely stone ash and sand, reduces the impact of environmental damage when using chemical additives. Variations of materials mixture were 0%, 5%, 10%, 15%, and 20%. To determine the strength of the soil that has been mixed with natural materials, a test called the California Bearing Ratio (CBR) is carried out. The CBR laboratory test illustrates the conditions that will occur in the field. This CBR test was carried out using soaked and un-soaked methods. For testing by soaking, mixed variations of 0% and 5% obtained a low CBR value. The highest was 10% mixed variation and decreased to 15% and 20%. The CBR test without soaking had the highest CBR value at 5% mixture variation and the lowest at 0%. Adding a mixture variation above 5% causes the CBR value to decrease slowly. The results of the tests show that soaking the soil makes the soil condition saturated with water so that the resulting CBR value becomes very low

トルコにおける2012年義務教育改革 : 宗教関連選択科目の新設とイマーム・ハティプ中学校の再開に注目して

A conventional and seismic method for determining the ultimate pile bearing capacity was proposed and compared. The Spectral Analysis of Surface Wave (SASW) method is one of the non-destructive seismic techniques that do not require drilling and sampling of soils, was used in the determination of shear wave velocity (Vs) and damping (D) profile of soil. The soil strength was found to be directly proportional to the Vs and its value has been successfully applied to obtain shallow bearing capacity empirically. A method is proposed in this study to determine the pile bearing capacity using Vs and D measurements for the design of pile and also as an alternative method to verify the bearing capacity from the other conventional methods of evaluation. The objectives of this study are to determine Vs and D profile through frequency response data from SASW measurements and to compare pile bearing capacities obtained from the method carried out and conventional methods. All SASW test arrays were conducted near the borehole and location of conventional pile load tests. In obtaining skin and end bearing pile resistance, the Hardin and Drnevich equation has been used with reference strains obtained from the method proposed by Abbiss. Back analysis results of pile bearing capacities from SASW were found to be 18981 kN and 4947 kN compared to 18014 kN and 4633 kN of IPLT with differences of 5% and 6% for Damansara and Kuala Lumpur test sites, respectively. The results of this study indicate that the seismic method proposed in this study has the potential to be used in estimating the pile bearing capacity

Durability of Slag Based Geopolymer Stabilized Clay with High Moisture Condition

Clay soils, characterized by their cohesiveness and water retention capacity, exhibit low aeration and tend to swell when water is absorbed, leading to subsequent contraction. The moisture content significantly affects the properties of marine clay, resulting in low strength and high compressibility. Traditional stabilizers like lime, cement, gypsum, fly ash, GGBS, and zeolite have been extensively studied for their ability to enhance the compressive strength, reduce swelling potential, and improve the overall durability of the soil. These stabilizers offer numerous benefits in terms of soil properties and have been extensively researched. A total of 27 GGBS-treated specimens and 7 cement-treated specimens were cast and tested for the strength and durability characteristic. In the study, the variables are binder content of 10%, 20%, and 30%, activator/binder ratio of 0.5, 0.75, and 1.0, and initial moisture content of 0.75wL, wL, and 1.25wL. Several kinds of experiments were carried out in order to investigate the qualities of stabilized clays, such as their unconfined compressive strength and their resistance to the effects of wetting and drying cycles. As the initial moisture content of the soil increased, the strength of the treated specimens decreased under unconfined compression and flexure. As a result, increasing the binder dose was necessary in order to achieve the strength requirements for high water content soils. Thus, it showed the use of a slag-geopolymer binder for the purpose of stabilizing soft soil is an alternative that is both effective and environmentally friendly

Estimate of Small Stiffness and Damping Ratio in Residual Soil Using Spectral Analysis of Surface Wave Method

Research in the important parameters for modeling the dynamic behavior of soils has led to rapid development of the small strain stiffness and damping ratio for use in the seismic method. It is because, the experimental determination of the damping ratio is problematic, especially for hard soils sample. Many researchers have proved that the surface wave method is a reliable tool to determine shear wave velocity and damping ratio profiles at a site with very small strains level. Surface wave methods based on Rayleigh waves propagation and the resulting attenuation curve can become erroneous when higher modes contribute to the soil’s response. In this study, two approaches has been used to determine the shear strain amplitude and damping ratio of residual soils at small strain level using Spectral Analysis of Surface Wave (SASW) method. One is to derive shear strain amplitude from the frequency-response curve and the other is to derive damping ratio from travel-time data. Then, the results are compared to the conventional method

Estimate of Small Stiffness and Damping Ratio in Residual Soil Using Spectral Analysis of Surface Wave Method

Research in the important parameters for modeling the dynamic behavior of soils has led to rapid development of the small strain stiffness and damping ratio for use in the seismic method. It is because, the experimental determination of the damping ratio is problematic, especially for hard soils sample. Many researchers have proved that the surface wave method is a reliable tool to determine shear wave velocity and damping ratio profiles at a site with very small strains level. Surface wave methods based on Rayleigh waves propagation and the resulting attenuation curve can become erroneous when higher modes contribute to the soil’s response. In this study, two approaches has been used to determine the shear strain amplitude and damping ratio of residual soils at small strain level using Spectral Analysis of Surface Wave (SASW) method. One is to derive shear strain amplitude from the frequency-response curve and the other is to derive damping ratio from travel-time data. Then, the results are compared to the conventional method

Relationship between Shear Wave Velocity and SPT-N Value for Residual Soils

The shear wave velocity (Vs) is an important dynamic parameter in the field of geotechnical engineering. One of the surface wave methods is Spectral Analysis of Surface Wave (SASW) has received attention in obtaining the shear wave velocity (Vs) profile by analysing the dispersion curve. SASW is a non-destructive test, fast and time-effective for field survey. Thus, this paper proposed the application of SASW method to obtain the shear wave velocity (Vs) to represent the soil profile. This paper aims to determine the shear wave velocity (Vs) profile using SASW method, where the testing has been conducted at three site of residual soils located in Damansara, Kuala Lumpur and Nilai area. In this study, it shows that the soil profile obtained from shear wave velocity value is similar pattern with profile that obtained using Standard Penetration Testing (SPT), which conventional used in field. The shear wave velocity are proportionally increase with depth

Relationship between Shear Wave Velocity and SPT-N Value for Residual Soils

The shear wave velocity (Vs) is an important dynamic parameter in the field of geotechnical engineering. One of the surface wave methods is Spectral Analysis of Surface Wave (SASW) has received attention in obtaining the shear wave velocity (Vs) profile by analysing the dispersion curve. SASW is a non-destructive test, fast and time-effective for field survey. Thus, this paper proposed the application of SASW method to obtain the shear wave velocity (Vs) to represent the soil profile. This paper aims to determine the shear wave velocity (Vs) profile using SASW method, where the testing has been conducted at three site of residual soils located in Damansara, Kuala Lumpur and Nilai area. In this study, it shows that the soil profile obtained from shear wave velocity value is similar pattern with profile that obtained using Standard Penetration Testing (SPT), which conventional used in field. The shear wave velocity are proportionally increase with depth

Investigation of bedrock at the hilly area using common array profiling spectral analysis of surface waves method

Locating hard layers or bedrock is particularly important in deep subsurface exploration. However, due to the scale effect of conventional testing, it is sometimes difficult to provide a greater overview of the subsurface conditions. This motivates a method that is capable of providing better resolution to a certain depth. This paper presents an investigation of bedrock using a nondestructive method at the hilly area as a supportive method to the existing borehole. The borehole recorded granite at respectively at 25 and 24m. CAP-SASW method that is employed successfully mapping the interested area. The result showed that the granite is considered as a slightly weathered rock with shear wave velocity ranging from 850-1600 m/s

Assessment of soil compaction properties based on surface wave techniques

Soil compaction plays an important role in every construction activities to reduce risks of any damage. Traditionally, methods of assessing compaction include field tests and invasive penetration tests for compacted areas have great limitations, which caused time-consuming in evaluating large areas. Thus, this study proposed the possibility of using non-invasive surface wave method like Multi-channel Analysis of Surface Wave (MASW) as a useful tool for assessing soil compaction. The aim of this study was to determine the shear wave velocity profiles and field density of compacted soils under varying compaction efforts by using MASW method. Pre and post compaction of MASW survey were conducted at Pauh Campus, UniMAP after applying rolling compaction with variation of passes (2, 6 and 10). Each seismic data was recorded by GEODE seismograph. Sand replacement test was conducted for each survey line to obtain the field density data. All seismic data were processed using SeisImager/SW software. The results show the shear wave velocity profiles increase with the number of passes from 0 to 6 passes, but decrease after 10 passes. This method could attract the interest of geotechnical community, as it can be an alternative tool to the standard test for assessing of soil compaction in the field operation

Assessment of soil compaction properties based on surface wave techniques

Soil compaction plays an important role in every construction activities to reduce risks of any damage. Traditionally, methods of assessing compaction include field tests and invasive penetration tests for compacted areas have great limitations, which caused time-consuming in evaluating large areas. Thus, this study proposed the possibility of using non-invasive surface wave method like Multi-channel Analysis of Surface Wave (MASW) as a useful tool for assessing soil compaction. The aim of this study was to determine the shear wave velocity profiles and field density of compacted soils under varying compaction efforts by using MASW method. Pre and post compaction of MASW survey were conducted at Pauh Campus, UniMAP after applying rolling compaction with variation of passes (2, 6 and 10). Each seismic data was recorded by GEODE seismograph. Sand replacement test was conducted for each survey line to obtain the field density data. All seismic data were processed using SeisImager/SW software. The results show the shear wave velocity profiles increase with the number of passes from 0 to 6 passes, but decrease after 10 passes. This method could attract the interest of geotechnical community, as it can be an alternative tool to the standard test for assessing of soil compaction in the field operation