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"To analyze the stability of landfill waste, it is necessary to know the geotechnical characteristics of the solid waste material, especially the parameters related to the stability calculation such as the strength parameters (cohesion and friction angle). The physical properties of the materials are also important, as well as the composition of the waste. This study conducts laboratory and field tests to obtain the aforementioned characteristics from a typical urban landfill in Indonesia. The case study is taken to be the TPST Bantargebang landfill. Due to the difficulties in obtaining an undisturbed sample from landfill waste, a laboratory test was conducted using artificial solid waste samples. The strength parameters of the artificial waste samples were determined using a direct shear test. Besides the laboratory test, field tests (cone penetration test (CPT) and dynamic cone penetrometer test (DCPT)) were also conducted on the closed landfill zones in TPST Bantargebang to obtain the typical bearing capacity of the fill materials. The results of the direct shear test show that the cohesion value of the waste material aligns with the initial compression: higher compression results in higher cohesion, while the contrary applies to the friction angle. The cohesion values range from 0 to 41 kPa, and the friction angle ranges from 0 to 26°. The cone resistance value (qc) up to a depth of 10 m is in the range of 2 to 10 MPa. The equivalent CBR (California Bearing Ratio) value from the DCPT ranges from 4% to 21%. Despite the large variability of the bearing capacity at the top layers, as shown by the DCPT results, the CPT results in the field reveal that the bearing capacity (also the strength characteristics) of the waste materials shows linear increase in line with the depth."

"ABSTRAKFor dynamic excitation, it is convenient to idealize homogeneous soil under a base mat by a semi-infinite truncated cone. It is easy to analyze the cone model for vertical and horizontal translation, as well as for rocking and torsional rotation. The accuracy by comparison to rigorous half-space solutions is quite adequate for practical applications. Time-domain computational methods for translational and rotational motions are described in both the stiffness and flexibility formulations and elucidated by examples. The infinite cone is dynamically equivalent to a discrete element representation of the soil, consisting of an interconnection of a small number of masses, springs, and dashpots. As an alternative to the physical-component model, the response may be determined directly by simple recursive numerical procedures. The recursive methods are exact and particularly well suited for hand calculations of short-duration excitations."

"Akibat hujan deras yang terus turun selama lebih dari 3 jam, lereng penyangga rel kereta di Cilebut, Bogor, mengalami kelongsoran. Kelongsoran menyebabkan rel kereta jalur Bogor menuju Jakarta menggantung dan tidak dapat dilalui, empat tiang listrik rubuh, serta puluhan rumah warga yang berada di bawahnya mengalami kerusakan. Sebagai upaya mengidentifikasi faktor penyebab kelongsoran tersebut, dilakukan analisis kestabilan pada lereng tersebut berdasarkan beberapa variasi pembebanan dengan melihat pengaruh rembesan atau seepage akibat keberadaan sungai yang letaknya tidak terlalu jauh dari lereng. Analisis seepage dilakukan dengan menggunakan metode steady-state, sementara analisis stabilitas lereng menggunakan metode limit equilibrium. Dari hasil analisis stabilitas lereng, kondisi sebenarnya ketika terjadi longsor yaitu saat terjadi hujan dan hanya ada beban kendaraan memang sudah menunjukkan kondisi yang cukup kritis dengan faktor keamanan mendekati 1.000, sementara kondisi yang paling kritis berdasarkan hasil analisis adalah ketika terdapat luapan air dari sungai akibat hujan dan terjadi gempa, serta ada kereta yang melintas di jalur arah Jakarta dengan faktor keamanan sebesar 0.965. Kondisi yang paling kritis dari hasil analisis tersebut kemudian menjadi acuan dalam merencanakan alternatif perkuatan lereng dengan menggunakan soil nail dan geotextile. Kenaikan muka air tanah akibat hujan, pembebanan di area lemah, serta adanya getaran akibat gempa merupakan beberapa hal yang menyebabkan kondisi lereng menjadi tidak aman.

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After heavy rains fell for more than 3 hours, slope that supports railway tracks in Cilebut, Bogor, suffered a landslide. This landslide/slope failure made Bogor-to-Jakarta track to hang and cut, four electric poles collapsed, and dozens of houses were damaged underneath. As an effort to identify factors causing the landslide, slope stability analysis is applied to the slope with some loading variations and considering the effect of seepage from a river near the slope.

Seepage analysis is done using steady-state method, while slope stability analysis is done using limit equilibrium method. From the results of slope stability analysis, the actual condition in the event of landslide occur when rain falls and there is only vehicle load already shows considerable critical condition with a safety factor close to 1,000, while the most critical conditions based on the results of the analysis is that when there is a surge of water from the river due to long-duration rain, a train passing Bogor-to-Jakarta track, and an earthquake, with a safety factor of 0.965.

The most critical conditions of the analysis are then become a reference in planning alternatives for slope reinforcement using soil nail and geotextile. Rise in groundwater levels due to rain, loading in the weak area, and the vibrations caused by the earthquake are several things that cause slope condition becomes unsafe."

"This book provides a snapshot of the research activities of the Institute of Geotechnical Engineering, University of Natural Resources and Life Sciences in Vienna, Austria. The topics are broad ranged including; Centrifuge model testing, Constitutive model, Granular physics, Numerical simulation, and Soil bioengineering.The topics reflect our geotechnical research in a changing world. Traditional topics in foundation engineering are fading out and new topics are emerging. The European Commission is gratefully acknowledged for funding the following projects within its program FP7 and Horizon2020: MUMOLADE (Multiscale modelling of landslide and debris flow), REVENUES (Reinforced Vegetation Numerical Evaluation of Slopes) and GEORAMP (Geohazards - Risk Assessment, Mitigation and Prevention)."

"This study investigated the possibility of developing a synthetic fill material by combining industrial waste materials, thus, integrating the properties of cohesion and friction as a replacement for natural soil. Biosolids and steel slag were selected for proportioning of the synthetic fill material. They were blended in different proportions and the geotechnical properties of the various blends were investigated to determine the strength and bearing of the blended synthetic material for fill applications. The results of the investigation were encouraging with the index properties of the blends better than those of biosolids. It was found that 25% to 40% steel slag blending produced the maximum strength and bearing. The investigation revealed that blending of industrial waste materials has the potential to perform the function of a synthetic fill material in road embankments and backfills. However, further studies are recommended to investigate its long term compressibility and permeability and further improvement of bearing to meet local standards."

"The book comprises selected proceedings of the 2016 annual conference of the Indian Geotechnical Society. The technical papers presented on the theme “Geotechnical Characterisation and Geoenvironmental Engineering” highlight the modified geotechnical properties of soil admixed industrial waste and also the characteristics of soil with different pore fluid under varying test conditions. The major topics covered are (i) characterisation of soils, rocks and synthesised materials and (ii) geoenvironmental engineering and behaviour of unsaturated soil. This book will prove a valuable reference for researchers and practicing engineers alike."

"Dengan meningkatnya volume timbulan sampah, maka keterbatasan lahan menjadi permasalahan ketika pengoperasian TPA. Sehingga proses mempercepat proses dekomposisi perlu untuk dilakukan. Tujuan dari penelitian untuk menginvestigasi pengaruh resirkulasi air lindi terhadap degradasi kualitas sampah dan air lindi pada bioreaktor landfill. Penelitian menggunakan tanki toren yang berisi tiga lapisan dengan berat total 300 kg. Kadar air sampah ditingkatkan dengan resirkulasi lindi 1,5 L dan air 1,4 dengan waktu pengamatan 150 hari. Hasil menunjukan parameter pH lindi yakni 5,43-7,9, rerata reduksi volume sampah mencapai 84,09%, rerata temperatur yakni 29-38,90C, rerata total mikroorganisme (mesofilic) yakni 0,06-468,5x107CFu/gram, rerata rasio karbon dan nitrogen yakni 8,7:1-19,3:1, field capacity yakni 0,47 L/kg, BOD5 yakni 24,5-1899,4 mg/l, COD yakni 2720-41600 mg/l.

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As increasing volume of waste generation, land constraints will be problem when landfill already operated. So that rate decomposition of waste must be considered. The purpose of this study is to investigate the impact of leachate recirculation on the degradation of refuse and leachate quality at bioreactor landfill. The study was carried out using columns containing three layers of refuse with total of waste is 300 kg. Water content is improved with injection by flushing with leachate 1,5 L and tap water 1,4 L over 150 days. Results show 5,43-7,9 for pH, 84,09% for average of volume reduction, 29-38,90C for average of temperature, 0,06-468,5x107CFu/gram for mesophilic micro., 8,7:1-19,3:1 for average of carbon and nitrogen ratio, 0,47 L/kg for field capacity, 24,5-1899,4 mg/l for BOD5, 2720-41600 mg/l for COD."

"This book presents articles covering a wide spectrum of topics in geotechnical engineering, including properties of soils, unsaturated soil mechanics, ground improvement, liquefaction and seismic studies, soil-structure interaction and stability analysis of man-made and natural slopes.The contributing authors are renowned researchers in their respective fields, which include soft ground improvement, seismic response of retaining structure using soil-structure Interaction (SSI) principles, and unsaturated soils. Based on keynote addresses and invited talks presented at the Indian Geotechnical Conference 2016, this book will prove a valuable resource for practicing engineers and researchers in the field of geotechnical engineering."