15. Ground freezing is a process of making water-bearing strata temporarily impermeable and to increase their compressive and shear strength by transforming joint water into ice. Tanahbekuadalahproses pembuatanair-bearing stratasementarakedap air danuntuk meningkatkan kekuatantekan dangesermerekadengan mengubahairmenjadi esbersama. Freezing is normally used to provide structural underpinning; temporary supports for an excavation or to prevent ground water flow into an excavated area. Pembekuanbiasanya digunakanuntuk menyediakanfondasistruktural; dukungansementara untukpenggalianatau untuk mencegahaliran air tanahke suatu daerahdigali. Successful freezing of permeable water-bearing ground affects simultaneously a seal against water and substantial strengthening of incoherent ground. PembekuanSuksespermeabelairbantalantanahmempengaruhisecara bersamaansegelterhadapairdan penguatansubstansialtanahmembingungkan. No extraneous materials need to be injected and apart from the contingency of frost heave, the ground normally reverts to its normal state. Tidak adabahanasingharusdisuntikkandanterpisah darikontingensiheavees, tanahbiasanyaberalihke keadaan normal. It is applicable to a wide range of soils but it takes considerable time to establish a substantial ice wall and the freeze must be maintained by continued refrigeration as long as required. Hal iniberlaku untukberbagai jenis tanahtetapi membutuhkan waktuyang cukupuntuk membangundindingesyang besardanpembekuanharus dijagaolehlanjutanpendinginanselamadiperlukan. 14. Vertical drains are installed under a surcharge load to accelerate the drainage of impervious soils and thus speed up consolidation Drainase vertikaldipasangdi bawah bebanbiaya tambahanuntuk mempercepatdrainasetanahtahandan dengan demikianmempercepatkonsolidasi These drains provide a shorter path for the water to flow through to get away from the soil Saluraninimenyediakan jaluryang lebih pendek untukairmengalir melaluiuntuk menjauh daritanah Time to drain clay layers can be reduced from years to a couple of months Waktuuntuk menguraslapisantanah liatdapat dikurangidaritahunkebeberapabulan 1. Soil Modification = Improvement of soil behavior Soil Stabilization = Increases strength and structural values ModifikasiTanah=Peningkatanperilaku tanah Stabilisasitanah=Meningkatkannilai-nilaikekuatan danstruktur 9. Vibro-Replacement Stone Columns extends the range of soils that include cohesive soils. Vibro-Penggantian KolomBatumemperluas jangkauantanahyangmeliputitanah kohesif. Densification and/or reinforcement of the soil with compacted granular columns or âstone columnsâ is accomplished by either top-feed or the bottom-feed method. Densifikasidan/ataupenguatantanahdengan kolomgranulardipadatkanatau"kolom batu" dilakukan denganbaikatasumpanataumetode bottom-feed. Cohesive, mixed and layered soils generally do not densify easily when subjected to vibration alone. The Vibro-Replacement Stone Column technique was developed specifically for these soils, effectively extending the range of soil types that can be improved with the deep vibratory process. With Vibro-Replacement Stone Columns, columns of dense, crushed stone are designed to increase bearing capacity, reduce settlement, aid densification and mitigate the potential for liquefaction, and improve shear resistance. Kohesif, dicampurdanberlapistanahumumnya tidakdensifymudahketika mengalamigetaransendiri. TheVibro-Penggantian BatuteknikKolomdikembangkan khusus untuktanah ini, secara efektifmemperluas jangkauanjenis tanahyangdapat ditingkatkandengan prosesgetarandalam.DenganVibro-Penggantian BatuKolom, kolompadat, batu pecahdirancanguntuk meningkatkandaya dukung, mengurangipemukiman, bantuandensifikasidan mengurangipotensilikuifaksi, danmeningkatkan ketahanangeser. · The Vibro-Replacement Stone Column Process: · t heVibro-Penggantian BatuKolomProses: 1. Reduces foundation settlement. 2. Mengurangipenyelesaianpondasi. 3. Increases bearing capacity, allowing reduction in footing size. 4. Meningkatkandaya dukung, yang memungkinkanpenguranganukuranpijakan. 5. Provides slope stabilization. 6. Menyediakanstabilisasi lereng. 7. Permits construction on fills. 8. Izinkonstruksimengisi. 9. Permits shallow footing construction. 10. Izinkonstruksipondasidangkal. · Dynamic compaction Definition: pemadatanDinamis definisi: · method involves the systematic dropping of heavy weights, 100 to 400kN, from a height of 5 to 30m, in a pattern designed to remedy poor soil conditions at the proposed building site. · â¢Metodemelibatkanmenjatuhkansistematisbeban berat, 100ke400kN, dari ketinggian5 sampai30 m, dalam polayang dirancanguntuk memperbaikikondisi tanahyang burukdidiusulkanmembangun situs. Why dynamic compaction is used? Mengapapemadatandinamisdigunakan? · To increase in-situ density. · Untuk meningkatkanin-situkepadatan. · Improve the bearing capacity and consolidation characteristics of soils (or waste materials). · Meningkatkandaya dukungdan karakteristikkonsolidasitanah(atau bahan limbah). · Improve in-situ permeability and/or reduce liquefaction potential. · Meningkatkanin-situpermeabilitasdan/ataumengurangipotensilikuifaksi. · Preloading Preloading · Known as âpre-compressionâ. · Dikenal sebagai"pra-kompresi". · It is the process of placing additional vertical stress on a compressible soil to remove pore water over time. The pore water dissipation reduces the total volume causing settlement. · Iniadalah prosesmenempatkanstresvertikaltambahanpadatanahkompresibeluntuk menghilangkan airporidari waktu ke waktu. Disipasiair porimengurangitotalvolume yangmenyebabkanpemukiman. · the consolidation of the soils is time dependent , delaying construction projects making it a non-feasible alternative · konsolidasitanahtergantungwaktu, menundaproyek-proyek konstruksimembuatnya menjadialternatifnon-layak NO 10. Soils Treated: · Organic Silt. · Silts and Clays. · Soft Clay. · Dredged Material. Design Considerations: · Bearing Capacity · Slope Stability · Degree of Consolidation · TanahDiobati: â¢OrganicSilt. â¢siltsdanlempung. â¢LembutClay. â¢dikerukMaterial. PertimbanganDesain: â¢KapasitasBantalan â¢StabilitasLereng â¢GelarKonsolidasi Applications aplikasi · Reduce Post-Construction Settlement · Reduce Secondary Compression · Densification · Improve Bearing Capacity. · â¢MengurangiPost-Construction Settlement â¢MengurangiKompresiSekunder â¢Pemadatan â¢MeningkatkanBantalanKapasitas. · 12. GROUTING: Defined as the injection of a special liquid or slurry material called grout into the ground for the purpose of improving the soil or rock · GROUTING: Ditetapkansebagaiinjeksibahancair ataububurkhusus yang disebutnatke dalam tanahuntuk tujuanmeningkatkantanah atau batuan · Types of grouts · Cementitious grouts · Chemical grouts · jenisgrouts -Semengrouts -GroutsKimia · GROUTING METODS : Intrusion grouting · Consists of filling joints or fractures with grout · Primary benefit is reduction in hydraulic conductivity · Used to prepare foundation and abutments for dams · Usually done using cementitious grouts · â¢METODEGROUTING: Intrusiongrouting -Terdiri darimengisisendiataupatah tulangdengannat -Manfaatutama adalahpengurangankonduktivitashidrolik -Digunakanuntuk mempersiapkanpondasidan penyanggauntukbendungan -Biasanyadilakukan dengan menggunakangroutssemen · Permeation grouting · Injection of thin grouts into the soil · Once the soil cures, becomes a solid mass · Done using chemical grouts · Used for creating groundwater barriers or preparign ground before tunneling · â¢Permeasigrouting -Injeksigroutstipiske dalam tanah -Setelahobattanah, menjadimassayang solid -Selesaimenggunakangroutskimia -Digunakan untukmenciptakanhambatanair tanahatau mempersiapkantanahsebelumtunneling · Compaction grouting · When low-slump compaction grout is injected into granular soils, grout bulbs are formed that displace and densify the surrounding loose soils. · Used to repair structures that have excessive settlement · Pemadatangrouting -Ketikarendahkemerosotanpemadatannatdisuntikkan ketanahgranular, lampunatterbentukmenggusuritu danmerapatkantanahkehilangansekitarnya. -Digunakan untukstrukturperbaikanyang memilikipenyelesaianyang berlebihan · Jet grouting · Developed in Japan · Uses a special pipe with horizontal jets that inject grout into the ground at high pressures · Jet grouting is an erosion/replacement system that creates an engineered, in situ soil/cement product known as Soilcretesm. Effective across the widest range of soil types, and capable of being performed around subsurface obstructions and in confined spaces, jet grouting is a versatile and valuable tool for soft soil stabilization, underpinning, excavation support and groundwater control. · Jetgrouting -Dikembangkandi Jepang -Menggunakanpipakhusus denganjethorisontalyangmenyuntikkannatke dalam tanahpada tekanan tinggi -Jetgroutingadalah sistemerosi/penggantiyang menciptakanrekayasa, dalam produktanah/semenin situyang dikenal sebagaiSoilcrete. Efektifdi seluruhjangkauan terluasjenis tanah, danmampuyang dilakukansekitar penghalangbawah permukaandandi ruang terbatas, jetgroutingadalah alatserbagunadan berhargauntukstabilisasitanah lunak, yang mendukung, dukunganpenggaliandan kontroltanah. 11. Precompression :Simply place a surcharge fill on top of the soil that requires consolidation Once sufficient consolidation has taken place, the fill can be removed and construction takes place Surcharge fills are typically 10-25 feet thick and generally produces settlement of 1 to 3 feet. Most effective in clay soil Precompression: Cukupmenempatkanbiaya tambahanmengisidi atastanahyang memerlukankonsolidasi Setelahkonsolidasiyang cukuptelah terjadi, mengisidapat dihapusdan konstruksiberlangsung Mengisibiaya tambahanbiasanya10-25kaki tebaldan umumnyamenghasilkanpenyelesaian1 sampai 3meter. Paling efektif dalamtanahliat ADVANTAGES :Requires only conventional earthmoving equipment, Any grading contractor can perform the work, Long track record of success DISADVANTAGES :Surcharge fill must extend horizontally at least 10 m beyond the perimeter of the planned construction, which may not be possible at confined sites Transport of large quantities of soil required Surcharge must remain in place for months or years, thus delaying construction KEUNGGULAN: Membutuhkanhanya peralatanearthmovingkonvensional, Setiapkontraktorpenilaiandapat melakukanpekerjaan, track recordpanjangkeberhasilan Kekurangan: Surchargemengisiharusmemperpanjanghorizontalsetidaknya10mdi luarperimeterrencana pembangunan, yangtidak mungkindi lokasiterbatas Transportasidalam jumlah besartanahyang dibutuhkan Surchargeharustetap di tempatselama berbulan-bulanatau bertahun-tahun, sehingga menundakonstruksi · Vertical drains :Vertical drains are installed under a surcharge load to accelerate the drainage of impervious soils and thus speed up consolidation These drains provide a shorter path for the water to flow through to get away from the soil Time to drain clay layers can be reduced from years to a couple of months Vertikalsaluran: saluranvertikaldipasang di bawahbebanbiaya tambahanuntuk mempercepatdrainasetanahtahandan dengan demikianmempercepatkonsolidasi Saluraninimenyediakan jaluryang lebih pendek untukairmengalir melaluiuntuk menjauh daritanah Waktuuntuk menguraslapisantanah liatdapat dikurangidaritahunkebeberapabulan · In-situ densification : Most effective in sands · Methods used in conventional earthwork are only effective to about 2 m below the surface · In-situ methods like dynamic deep compaction are for soils deeper than can be compacted from the surface â¢In-situdensifikasi: Paling efektifdipasir â¢Metodeyang digunakan dalampekerjaan tanahkonvensionalhanya efektifsekitar2m di bawahpermukaan â¢In-situmetode sepertipemadatandinamismendalam adalahuntuk tanahyang lebih dalamdaripada yang bisadipadatkandari permukaan · Grouting : Defined as the injection of a special liquid or slurry material called grout into the ground for the purpose of improving the soil or rock · Types of grouts · Cementitious grouts · Chemical grouts · Reinforcement: Soil is stronger in compression than in tension · To improve strength in tension, geosynthetics placed in soil for soil reinforcement · Grouting: Ditetapkansebagaiinjeksibahancair ataububurkhusus yang disebutnatke dalam tanahuntuk tujuanmeningkatkantanah atau batuan â¢Jenisgrouts -Semengrouts -GroutsKimia â¢Penguatan: Tanahkuatdikompresidaridalam ketegangan â¢Untukmeningkatkan kekuatandalam ketegangan, Geosyntheticsditempatkandalam tanahuntukperkuatan tanah NO 7: alatpemadat : ôSmooth Wheel Roller : Alatpemadatterdiri darirodabajadengan tekanankontaksampai dengan 400 kPa, cocok untuksemuajenis tanah. Luascakupan pemadatanselebarluas roda yang kontak dengantanah yang dipadatkan Rubber Tire Roller : Terdiridari 3 â 6 roda bandengantekanan 700 kPa, cocokuntuk segalajenistanah. Luas cakupanpemadatan 80% dariluasroda yangkontakdengan tanah yang dipadatkaN SheepsfootRoller : Terdiridarisejumlah kakibajaberukuran 150 mm â 250 mm dengan luaspenampang 30 â 80 cm2melekatpada drum baja. Luascakupan pemadatan 8 â 12% luas drum dengan tekanankontak 1400 â 7000 kPa. Dapatdiisi air, cocokuntuktanah kohesifsepertilempung Tamping Foot Roller : Miripsepertisheepsfoot rollerdenganluas cakupanpemadatan lebihtinggiyaitu 40% dantekanankontak 1400 â 8400 kPa. Baik untuktanahkohesifdan menghasilkanaksi static weight, kneading, impactdanvibrasi. Grid Roller : Alatpemadatdengan rodadari drum baja yangdilapisianyaman batanganbaja. Luas cakupanpemadatan 50%. Cocokdigunakan untuk material granular sepertipasir, gravel atautanahberbatu Baby Roller : Alatpemadat smooth wheel roller yangberukurankecil. Kemampuan 10 â 30 kPa. Aksi yang dihasilkan static weight danefekvibrasi Vibrating Plate : Alatpemadatberupa pelat, dikenalumum dengannama stamper. Digunakanpada area yangsempitdan area yangmempunyairesiko tinggijikadigunakan alatpemadatbesar seperti smooth wheel rollerdsb. StabilisasiMekanis - Bertujuanuntukmendapatkantanah yang bergradasibaik (well graded) sehinggadapatmemenuhispesifikasi yang diinginkan Ciri-cirikhasuntukpemilihanperbaikanmututanahdenganstabilisasimekanis (mencampurberbagaijenistanah): · Jenistanah yang dipakaiterdapatberdekatan satudenganlainnya, apabilasatudarijenis tanah yang dimaksudharusdiambildaritempat yangjauhtidakekonomisdanharusdicarikan metode lain · Apabilaspesifikasitelahditetapkandanditetapkan proporsidarimasing-masingbahancampuran yang akandicampurpencampurandilakukandibawah pengawasan yang ketatsehingga dapatdijaminhomogenitas