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Repair Performance Landslide and Slope Using Bore pile and Ground Anchor on Cipali Toll Road Km 103 Akhmudiyanto Akhmudiyanto; Paulus Pramono Rahardjo; Rinda Karlinasari
U Karst Vol 5, No 2 (2021): NOVEMBER
Publisher : Kadiri University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (4274.89 KB) | DOI: 10.30737/ukarst.v5i2.1583

Abstract

One of the causes of on-road collapse slopes is traffic load. Slope failure by road loads usually occurs due to several factors such as soil type, rainfall, land use. This study aims to determine landslide and slope repair performance using bore pile and ground anchor on Cipali Toll Road KM 103. The research method used in this study is the Finite element method. In this research, data collection, modeling parameter determination, slope stability analysis, slope reinforcement analysis, and reinforcement design were carried out with variations in bore pile and ground anchor dimensions. The software program used is a finite element program in the form of PLAXIS to analyze slope stability and estimate the slope failure area. The result of the study is that the R-Value inter is 0.25 with a 1.0341 safety factor. Best repair performance obtained from the addition of reinforcement with ground anchor 2 layer on bore pile 2 with a distance of 2 meters increased the safety factor to 1,913; Borepile capacity calculation with the calculation of normal force and moment iteration, the largest occurs in the DPT (Retaining Wall) stage with a normal load of -37.9 and a moment force of -471.15 which is still able to be borne by bore pile 1. The result of this study is expected to be benchmark and repair material to improve slope stability at km 103 Tol Cipali
Study of Anisotropy Characteristics of Bogor Volcanic Soil Yusi Sulastri; Paulus Pramono Rahardjo
U Karst Vol 5, No 1 (2021): APRIL
Publisher : Kadiri University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2700.687 KB) | DOI: 10.30737/ukarst.v5i1.1137

Abstract

Anisotropy in soil results from the deposition process which describes the characteristics of the soil grains or is caused by stress or from the consequences of stresses caused during deposition and subsequent erosion. All soils behave in general anisotropy and some exhibit undrained shear strength. This study conducted 2 tests, namely the first field testing with original soil samples in the form of CPTu and dilatometer. The CPTu test's objective is to determine the vertical soil parameters, while the dilatometer is to determine the horizontal soil parameters. This study indicates that the indication of anisotropy in all shear strength tests is evident in the results of the CPTu test and the Dilatometer test. TX - UU and consolidation show that the horizontal shear strength (Suh) is greater than the vertical slope shear strength (Suv). In this case, the ratio obtained for shear strength is Suh = 1.3 Suv. And from the results of the consolidation test in the laboratory, it was found that the horizontal compression index parameter  (Cc horizontal) was greater than the vertical (Cc vertical) and the horizontal coefficient of consolidation (Ch) is greater than the vertical coefficient of consolidation (Cv).
Evaluating Liquefaction Phenomenon Of Silty Sand Using Piezocone Penetration Test (CPTu) Albert Johan; Paulus Pramono Rahardjo; Budijanto Widjaja
U Karst Vol 6, No 1 (2022): APRIL
Publisher : Kadiri University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3773.405 KB) | DOI: 10.30737/ukarst.v6i1.2118

Abstract

Most investigations into liquefaction have focused on clean sandy soils, with time, evidence has grown that liquefaction is often associated with silty sand material. Sibalaya Village, which suffered the greatest damage from the Palu-Donggala earthquake, is dominated by silty sand material. Related to this issue, an experimental study is conducted in the laboratory to understand the behavior of excess pore pressure and the strength of the saturated silty sand under dynamic loading. The experimental study uses several sets of testing apparatus such as a shake table, chamber, and CPTu. The shake table provides a dynamic load for the soil sample. The chamber allows the field environment to be duplicated in the laboratory. The CPTu measures excess pore pressure and strength of the soil sample. The test results show that liquefaction can occur in silty sand material. However, the fine-grain particles cannot generate the overall pore water pressure in which the pore water pressure ratio can only reach 93% of the initial effective vertical stress. Liquefaction also generates increased pore water pressure and a decrease in soil strength. The increase of dynamic load will result in a shorter liquefaction starting time, and fine content strongly influences the pore water pressure behavior, especially on the rate of pore water pressure dissipation after liquefaction occurs. Therefore, based on this research, it is known that silty sand material can experience liquefaction and can have a longer liquefaction period due to its lower permeability.
The Determination of Downhole Dynamic Compaction Paramaters Based on Finite Element Analysis Martin Wijaya; Ahmad Kemal Arsyad; Aswin Lim; Paulus Pramono Rahardjo
Journal of the Civil Engineering Forum Vol. 8 No. 3 (September 2022)
Publisher : Department of Civil and Environmental Engineering, Faculty of Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jcef.3467

Abstract

Downhole dynamic compaction (DDC) has been commonly used in China to stabilize collapsible soil through the application of construction and demolition waste material (CDW). DDC basically forms a column inside the soil stratum which is similar to a stone column except DDC materials are put in sequence and then compacted by using DDC hammer. Due to its attractive features such as its big diameter, feasibility of using oversized material particles, rapid and simple construction technique, it is used as one of the ground improvement methods for an airport project in Indonesia. Despite of all the advantages provided by DDC, it is difficult to obtain DDC parameters from laboratory tests as it is difficult to replicate the compaction effort induced by the DDC hammer and laboratory tests are not commonly employed for oversized materials. Hence, alternative method is required to evaluate DDC parameters. In this study, static load test is conducted to determine load-deformation curve of the DDC pile. Soil parameters are first determined through soil test data such as standard penetration test (SPT), laboratory test and also pressure meter tests. Correlation between pressure meter tests and SPT test result is also carried in order to interpret the soil parameter at the site. Axisymmetric finite element analysis is then carried by using MIDAS GTS NX in order to back analyses DDC parameters by matching the simulation curve with load settlement curve of the DDC. In this paper, it is shown that back analysis using hardening soil model for DDC material can be used to match simulation curve with the load-deformation curve.
The site characterization of central jakarta soft soil using CPTu and laboratory test Andrianto Muliawan Permana; Paulus Pramono Rahardjo
Indonesian Geotechnical Journal Vol. 1 No. 1 (2022): Vol.1 , No.1, April 2022
Publisher : Himpunan Ahli Teknik Tanah Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1424.223 KB) | DOI: 10.56144/igj.v1i1.6

Abstract

Construction activities has been named as one of the contributing factors to Jakarta’s alarming rate of land subsidence, which ranges between 1 to 15 cm annually, and up to 28 cm in some locations. This problem is commonly known as settlement, and the affected soft soil is usually attributed to under-consolidating soil (UC). In regards to that matter, this study aims to characterize the soft soil layer in Central Jakarta using the Cone Penetration Test with pore pressure measurement (CPTu) and laboratory assessment. In addition, Undrained Shear Strength () and Pore Pressure Ratio (and ) methods were used to estimate the over-consolidation Ratio (OCR) values. The data collected from 94 boreholes and 30 CPTu showed the soft soil layers in Central Jakarta, which was dominated by high-plasticity silty clay (CH) and clayey silt (MH). The layers are detected between the depth of 0 – 25 m and are characterized by high natural moisture content, void ratio, liquidity index, and compression index values. Within this layer of under consolidated soils, the indication of relatively low dry unit weight was also present. Furthermore, the laboratory tests showed several correlations related to under-consolidating soil, i.e. void ratio to in-situ effective stress, void ratio to compression index, and compression index to natural moisture content. The CPTu test interpretations returned a number of under-consolidation soil layer samples in Central Jakarta. Moreover, the result also indicates the presence of under-consolidating properties, as well as normally consolidated and lightly over-consolidated.
The analysis of pile-pile cap behavior under static loading test using distributed fiber optic sensor Tanti Muliati; Paulus Pramono Rahardjo; Bondan Widi Anggoro; Ricky Setiawan
Indonesian Geotechnical Journal Vol. 1 No. 1 (2022): Vol.1 , No.1, April 2022
Publisher : Himpunan Ahli Teknik Tanah Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1187.673 KB) | DOI: 10.56144/igj.v1i1.7

Abstract

Pile-Pile cap behavior was investigated in this study through the utilization of fiber optic sensors to continuously transmit information along the bored pile at a reading interval of 40 mm during each cycle of the static loading test. It is important to note that the fiber optic cables were installed on the two sides of the bored pile connected up to the pile cap to monitor the stress distribution beneath the pile cap while fiber optic sensors were installed under the pile cap. The ultimate axial bearing capacity expected to be achieved using the pile-pile cap configuration was 190 tons x 250% but failure occurred when the load used was increased to 190% of the design load. Therefore, the strain measurement obtained from the Distributed Fiber Optic Sensor Technology was analyzed to obtain information on the load transfer, pile shortening, mobilized unit skin friction, and mobilized end bearing at the pile-pile cap. The load portion carried out by pile cap was approximated at 6% to 23% from the actual top load applied. It was also discovered that the fiber optic sensors initially installed were able to record the strain caused to the soil by the load on the pile cap. The strain measurements on the soil made the zone of influence due to the loading of the foundation to reach two times the length of the pile while the biggest zone of influence lies at the end of the foundation. From recorded strain, show higher strain from one side compared to the other, this may indicate eccentricity of the load.
Investigation of Pile Behavior Toward Abutment Construction using PLAXIS 3D: Case Study on Lembak Bridge Clinton Girsang; Paulus Pramono Rahardjo; Aswin Lim
U Karst Vol. 5 No. 1 (2021): APRIL
Publisher : Kadiri University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30737/ukarst.v5i1.1012

Abstract

Soil  as  a  subgrade  foundation  under  embankment  construction often  creates  problems  in  terms  of  stability  and  settlement. Therefore, it needs improvement by using preloading embankment. This article presents the investigation of pile behavior towards two scenarios  of  abutment  construction  using  Plaxis  3D,  a  three- dimensional  finite  element  program.  The  use  of  two  scenarios  of analysis was Method A. The abutment construction phase conduct without using a preloading embankment, and Method B, where a preloading  embankment  constructs  before  the  abutment construction.  The  case  study  location  at  the  Lembak  bridge. Compare  the  analysis  results  with  the  measured  data.  Results showed that Method A and Method B's pile deflection yielded four times  and  one  point  six  times  larger  than  the  measure  data, respectively.  Hence,  it  indicates  that  Method  B  recommends  for future construction of bridge abutment.
Performance Analysis Of “Toga” Foundation With Cap On Thick Soft Soil Based On Laboratory Models And Finite Element Analysis Melissa Kurnia; Paulus Pramono Rahardjo
U Karst Vol. 4 No. 2 (2020): NOVEMBER
Publisher : Kadiri University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30737/ukarst.v4i2.1072

Abstract

Various alternative foundations are offered depending on soil conditions from the results of soil investigations. In difficult soil types such as thick, soft soil layers, pile foundation is generally used to avoid the excess settlements, but deep foundations for small buildings are not the right solution when viewed from a cost perspective. One of the more economical foundations is to use the” toga” foundation, with a plate on top and a caisson underneath where the caisson can be inserted into the soil with an open end. Through this study, the carrying capacity of the” toga” foundation will be analyzed. Then the foundation will be made on a laboratory scale and tested with axial load. The load and deformation relationship were analyzed using PLAXIS 3D analysis. It can be concluded the performance of the ”toga” foundation on thick, soft soil can be used for two-floored buildings
Development Study of T-Z Curve Generated from Kentledge System and Bidirectional Test Nisa Utami Rachmayanti; Paulus Pramono Rahardjo
U Karst Vol. 5 No. 1 (2021): APRIL
Publisher : Kadiri University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30737/ukarst.v5i1.1090

Abstract

Pile loading tests to check the bearing capacity to support large loads. We can also use it to measure its deflection under lateral load.  There  are  two  tests:  the  axial  static  pile  load  test (Kentledge)  and  the  two-directional  static  pile  load  test (Bidirectional).  T-Z  curve  as  the  result  analysis  based  on  the instrumented  pile  test  data  describes  the  load  distribution  and mobilized skin friction along with the pile. Numbers of Vibrating Wire  Strain  Gauge  (VWSG)  mounted  in  several  depths  of  the bored  pile  and  two  tell-tale  on  top  and  toe  of  the  pile  used  as primary  data  in  this  research.  This  research  to  determine  the different  distribution  of  mobilized  skin  friction.  The  pile  from two different pile load test methods from the calculated t-z curve as  the  study  developed  from  both  methods  of  pile  test.  The research results that the kentledge system has bigger mobilized skin friction than in bidirectional test.
Study of Anisotropy Characteristics of Bogor Volcanic Soil Yusi Sulastri; Paulus Pramono Rahardjo
U Karst Vol. 5 No. 1 (2021): APRIL
Publisher : Kadiri University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30737/ukarst.v5i1.1137

Abstract

Anisotropy in soil results from the deposition process which describes the characteristics of the soil grains or is caused by stress or from the consequences of stresses caused during deposition and subsequent erosion. All soils behave in general anisotropy and some exhibit undrained shear strength. This study conducted 2 tests, namely the first field testing with original soil samples in the form of CPTu and dilatometer. The CPTu test's objective is to determine the vertical soil parameters, while the dilatometer is to determine the horizontal soil parameters. This study indicates that the indication of anisotropy in all shear strength tests is evident in the results of the CPTu test and the Dilatometer test. TX - UU and consolidation show that the horizontal shear strength (Suh) is greater than the vertical slope shear strength (Suv). In this case, the ratio obtained for shear strength is Suh = 1.3 Suv. And from the results of the consolidation test in the laboratory, it was found that the horizontal compression index parameter  (Cc horizontal) was greater than the vertical (Cc vertical) and the horizontal coefficient of consolidation (Ch) is greater than the vertical coefficient of consolidation (Cv).