CORE LOG AND CONE PENETRATION TEST APPROACH FOR BEARING CAPACITY ANALYSIS OF QUATERNARY DEPOSIT AND ITS CORRELATION TO FACIES DISTRIBUTION IN SOUTHERN BALI

Area development deals with optimal land use and the reduction of the risk of geological disasters. The coastal area of South Bali is prone to land settlement hazards. In order to mitigate the risk, it is important to understand the depositional environment of the area related to its bearing capacity and geological hazard risks. The aim of this research is to understand the subsurface depositional environment and quantifying its bearing capacity. Quantitative modeling was carried out to obtain the sediment-bearing capacity of the Pendungan area in Bali, Indonesia. The methods used in this research were the observation of borehole cores, the identification of the cone penetration test (CPTu) curves pattern, the sediment index property test, the soil strength laboratory, and bearing capacity analysis. Based on lithologic association, the CPTu curve pattern, and grain size analysis, there are three facies developing in the study area with different bearing capacity values. Generally, beach ridge sand has a higher bearing capacity (N-SPT value of 8 – 52) for shallow foundation than fluvial clay. Meanwhile, floodplain facies has the lowest bearing capacity (N-SPT value of 2 – 20).

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GEOENGINEERING INVESTIGATION OF AN EROSION INDUCED HIGHWAY STRUCTURAL FAILURE ALONG IFON – BENIN HIGHWAY, SOUTHWESTERN NIGERIA

Earth Science Malaysia ◽

10.26480/esmy.01.2020.51.60 ◽

2020 ◽

Vol 4 (1) ◽

pp. 51-60

Author(s):

Olumuyiwa Olusola Falowo ◽

Adekunle Aliu

Keyword(s):

Soil Analysis ◽

Cone Penetration Test ◽

Traffic Load ◽

Grain Size Analysis ◽

Size Analysis ◽

Soil Parameters ◽

Penetration Test ◽

Cone Penetration ◽

Clayey Silt ◽

Limit Test

Road infrastructural is one of the most important economic indices for development of a country. Therefore in-situ cone penetration test and laboratory soil analysis were performed at two failed segments along Ifon-Benin highway, with the aim of determining cause(s) and extent of the failure. The cone penetration test was carried out to a depth of about 20 m with a lateral spacing of 20 m along the roadway. The laboratory tests conducted were grain size analysis, Atterberg limit test, compaction test, California Bearing Ratio, and undrained unconfined triaxial test. The results revealed that all the soil parameters fell short of the federal ministry of works and housing specification of Nigeria, with plasticity index (>20%), % fines (>35%), CBR values (<80%) recommended, angle of friction and cohesion are less than minimum standard of 30° and 50 Kpa respectively. The CPT revealed predominant sandy silt to clayey silt topsoil and clay substratum with compressive strength of 20 – 40 KN/m2. The water level is higher than 3 m, consequently far below the road foundation baseline. Findings showed that the upper 6 m of the failed segments has been seriously affected by erosion and flooding. Subsequently the process resulted into excessive settlement of the silt/clayey-subgrade soil underneath the pavement structure. This makes the highway to settle largely under traffic load. In addition, incessant heavy flooding around the embankment/shoulder of the highway might have induced the failure, leading to looseness, and less-cohesion of the layers which invariably reduces subgrade support and weakens various pavement layers.

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PERBANDINGAN DAYA DUKUNG TIANG PANCANG BERDASARKAN PENGUJIAN CONE PENETRATION TEST (CPT) DAN STANDARD PENETRATION TEST (SPT) PADA TANAH BERPASIR

UKaRsT ◽

10.30737/ukarst.v4i1.793 ◽

2020 ◽

Vol 4 (1) ◽

pp. 109

Author(s):

I Wayan Ariyana Basoka

Keyword(s):

Bearing Capacity ◽

Field Tests ◽

Field Testing ◽

Cone Penetration Test ◽

Standard Penetration Test ◽

Pile Foundations ◽

Capacity Analysis ◽

Penetration Test ◽

Cone Penetration ◽

Spt Data

Design of building structure always related to the foundation, field testing is often done to test the bearing capacity of the soil in the form of a cone penetration test (CPT) and a standard penetration test (SPT). From the two field tests that are often done, it is necessary to research the amount of bearing capacity obtained through CPT and SPT data. This study uses a bearing capacity analysis of the pile foundation using CPT and SPT data in Pesanggaran, Bali, Indonesia. The analysis was carried out by comparing the bearing capacity of pile foundations using pile foundations with dimensions of 15 cm, 20 cm, 25 cm and 30 cm at a level of 10 meters. The results of the bearing capacity percentage are then compared. From the analysis conducted, the bearing capacity of pile foundations using CPT data has a higher value than the carrying capacity of poles using SPT data with a bearing capacity difference of 10,4-16,3%.Perancangan suatu struktur erat kaitannya dengan fondasi, pengujian lapangan yang sering dilakukan untuk mengetahui daya dukung fondasi berupa cone penetration test (CPT) dan standard penetration test (SPT). Dari dua pengujian lapangan yang sering dilakukan, maka perlu dilakukan dilakukan penelitian mengenai seberapa besar perbedaan hasil daya dukung yang diperoleh melalui data CPT dan SPT. Penelitian ini melakukan perbandingan analisis daya dukung fondasi tiang dengan menggunakan data CPT dan SPT di Pesanggaran, Bali, Indonesia. Analisis dilakukan dengan membandingkan daya dukung fondasi tiang menggunakan fondasi tiang berdimensi 15 cm, 20 cm, 25 cm, dan 30 cm pada kedalaman 10 meter. Hasil persentase daya dukung yang diperoleh kemudian dibandingkan. Dari analisis yang dilakukan, diperoleh daya dukung fondasi tiang menggunakan data CPT memiliki nilai lebih tinggi daripada daya dukung tiang menggunakan data SPT dengan perbedaan daya dukung 10,4-16,3%.

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