China Scan Tour on Ground Improvement Technologies Prepared by the ASCE G-I China Scan Tour Team Presented by Jie Han, Ph.D., PE, F.ASCE Glenn L. Parker Professor The University of Kansas
China Scan Tour on Ground Improvement Technologies from May 23 to 26, 2018 Followed by the 2 nd US-China Workshop on Ground Improvement Technologies on May 27, 2018 Organized by the G-I Soil Improvement Committee Sponsored by ASCE Geo-Institute Scope of the scan tour was: to identify and document new and implementable soil improvement technologies successfully used in China, with the goal of implementing the technologies into the current U.S. GeoTech Tools selection system.
China Scan Tour Team Prof. Jie Han, the University of Kansas (chair); Dr. Jose Clemente, Bechtel (co-chair) Dr. James Collin, the Collin Group (G-I board representative) Prof. Jie Huang, the University of Texas at San Antonio; Rob Jameson, Malcolm Prof. Prabir K. Kolay, Southern Illinois University Carbondale Prof. Cheng Lin, the University of Victoria, Canada; Dr. Guoming Lin, Terracon Dr. Antonio Marinucci, V2C Strategists, LLC; Dr. Lisheng Shao, Hayward Baker, Inc. Prof. Leon van Paassen, Arizona State University; Dr. David Yang, JAFEC USA, Inc.
Scan Tour Route
Project 1 Super-Deep (105 m/345 ft) Diaphragm Wall Shanghai Suzhou River Deep Drainage Suzhou river and Storage Facility Circular shafts 60 to 70 m (195 to 230 Huangpu river ft) deep Connected by 15.3 km (9.5 mi) of deep tunnels or pipelines with diameters ranging from 8 to 10 m (26 to 33 ft) Deep tunnels at depths of 40 to 60 m (130 to 195 ft) along the Suzhou River Credit: Shanghai Foundation Engineering Group CP., LTD., The Third Engineering Company
Project 1 Super-Deep (105 m/345 ft) Diaphragm Wall Shanghai (162 ft) (110 ft) (345 ft) (195 ft) (112 ft) (345 ft) Wall thickness = 3.3 to 4.9 ft Credit: Shanghai Foundation Engineering Group CP., LTD., The Third Engineering Company
Project 1 Super-Deep (105 m/345 ft) Diaphragm Wall Shanghai Max. excavation depth = 150m (492ft) Credit: Shanghai Foundation Engineering Group CP., LTD., The Third Engineering Company
Project 1 Super-Deep (105 m/345 ft) Diaphragm Wall Shanghai Credit: Shanghai Foundation Engineering Group CP., LTD., The Third Engineering Company
Super-Deep (105 m) Diaphragm Wall Max. excavation depth Max. excavation depth = 150m (492 ft) = 80 m (262 ft) Bauer BC40 hydromill mounted on Bauer BC40 on a Bauer MC96 & Support cranes and hydromills a Bauer MC128 crane Jintai SG60A hydromills
Super-Deep (105 m) Diaphragm Wall Milling a 300 mm (12 in) overlap into each primary panel using the hydromill. Pre-installed steel pipes for a post-construction freezing system at the panel ends. Option for exterior grouting patterns at the panel joints. Installation Over- Panel Measured Start Date Time No. Verticality break (hours) ZQ2 30 Dec 2017 120 1/3750 114% ZQ3 06 Jan 2018 76 1/1600 106% ZQ2-3 12 Jan 2018 297 1/1000 109% Credit: Shanghai Foundation Engineering Group CP., LTD., The Third Engineering Company
Super-Deep (105 m) Diaphragm Wall Hydration and settling tanks Desanding and desilting units Quality assurance / quality control performed on the bentonite slurry
Project 2 Dynamic Compaction + Vacuum Dewatering DDC typical suitable for partially saturated, non-plastic or low plasticity soil (e.g., PI< 8) where the groundwater table is sufficiently deep. DDC also effective for low permeability silt and clay, provided a proper drainage and/or dewatering system is installed Quick process, No fill or temporary matting (i.e., no preload or surcharge fill), Cost effectiveness for massive treatment, Straightforward, relatively simple installation, & construction equipment.
Project 2 Dynamic Compaction + Vacuum Dewatering • Improve dredged land for a 1 km (0.6 mi) long municipal road. The total treatment area is 28,000 m 2 (6.9 acre). • Achieve a minimum allowable bearing capacity of 120 kPa (2,500 psf), and a subgrade modulus no less than 25 MPa (3,625 psi) Credit: Shanghai GeoHabour Co.
Credit: Shanghai GeoHabour Co.
Project 2 Dynamic Compaction + Vacuum Dewatering Process 2 nd pass 3 rd pass 1 st pass Ironing tamping tamping tamping Settlement (cm) 23.4 31.3 7.1 10.8 Total settlement (cm) 72.6 Credit: Shanghai GeoHabour Co.
Dynamic Compaction + Vacuum Dewatering
Project 3 Detachable Anchor & Jet Grouting Excavation & Ground Water Cut-off by: • Detachable anchor • Jet grouting in anchor bonding zone • Soil mixing wall with recoverable W-beams • Two-story basement excavation to 12 m depth in very difficult soils • GWT at 0.7 m depth Credit: Zhejiang Zhongqiao Prestress Equipment Co., Ltd. & The Architectural Design and Research Inst. of Zhejiang Univ. Co., Ltd.
Project 3 Detachable Anchor & Jet Grouting Credit: Zhejiang Zhongqiao Prestress Equipment Co., Ltd. & The Architectural Design and Research Inst. of Zhejiang Univ. Co., Ltd. Detachable Anchor • Apply 2~3 ton tension on release strand • Unlock wedges • Recover working strands
Project 3 Detachable Anchor & Jet Grouting
Project 3 Detachable Anchor & Jet Grouting Reusable W-beams in the soil mixed columns Beams coated with a tar & grease mix Beams vertically inserted into fresh mixed column Above soil mixing, beams wrapped with styrofoam sheets & cast into concrete grade beam After excavation finished, W-beams pulled out
Project 4 Vacuum Consolidation Masive dredged land for a new city
Project 4 Vacuum Consolidation Credit: Huadong Engineering Corporation Ltd. Large reclaimed land (2.53 km 2 or 624 acres) • Vacuum preloading • Vacuum preloading + air injection • PVD electro-osmosis dewatering and consolidation
Project 4 Vacuum Consolidation • 3 to 10 meters dredged fill, soft silts & clays W = 50~80% • Native alluvial deposits of silts & clays W=30 ~ 70% • Target bearing capacity of 40 to 80 kPa for roads and Menard (2001) airport runways. • The long-term settlement target was 30 centimeters over 15 to 30 years. Credit: Dr. Huayang Lei
Project 4 Vacuum Consolidation Vacuum tubes & PVDs used to inject high pressure air to prevent clogging & facilitate water movements to speed up consolidation Credit: Dr. Huayang Lei Credit: Dr. Huayang Lei
Project 4 Vacuum Consolidation
Project 4 Vacuum Consolidation Vacuum consolidation + water surcharge
Project 4 Vacuum Consolidation
Project 4 Vacuum Consolidation Multiple small water-jet vacuum pumps used on another project site (not on the tour) Credit: Dr. Jie Han
Project 4 PVD Electro- Osmosis Test Jones et al. 2011
Project 4 PVD Electro-Osmosis • 1000 m 2 test area • measured settlement 500~ 750 mm in 32 days of electro- osmosis consolidation • Energy consumption 4~7 kwh/m 3 Credit: Hangzhou Shenyuan Environmental Sci-Tech Co. Ltd
Project 6 Soil Mixing, Pre-stressed Hollow Concrete Pile, Mass Mixing, & DAQ • New 50.8 km Hangzhou Beltline, 32.5-km long section to be constructed over soft soil • Soft soil thickness 2 ~ 44 m • Freeway embankment heights 2 ~ 6 m, & 5 to 6 m near bridge-approach embankment • Project site in a plain river network area of Hangjia Lake. No. Soil layer w (%) E s (MPa) c (kPa) φ(°) ② Soft soil 1 43.5 3.07 9.8 4.6 ③ Soft soil 2 40.9 3.23 10.3 5.3
Project 6 Counter Rotation DSM Counter rotation deep mixing: 0.5m column • 10m penetration • Grout pumped though inner casing • One electric motor with gear box to counter rotate inner and outer casing • Grease sealed between casings
Project 6 Wet Mass Mixing Soft Clay W ≤ 60% 1m 3 Mixing Ratio Cement Fly Ash Admix Cement Fly Ash Admix （ % ） （ % ） （ % ） （ Kg ） （ Kg ） （ Kg ） Full system DAQ 3.0 3.0 47.4 47.4 \ \ Credit: China Railway Construction Co. In-situ soil Moving direction Soft soil
Project 6 Pre-stressed Bamboo Shape Hollow Concrete Pile The bamboo-shaped or nodular pipe piling system (static drill rooted nodular [SDRN] pile system) Composite system combines pile foundations with soil mixing and grouting Start with a partially grouted and partially soil mixed hole. Insert hollow precast pipe sections Typically used for structural support of structures and in conjunction with column- supported embankments.
Project 6 Pre-stressed Bamboo Shape Hollow Concrete Pile
Other GI Technologies Presented in GI Workshop in Shanghai
Other GI Technologies Presented in GI Workshop in Shanghai Credit: Dr. Gang Zheng
Other GI Technologies Presented in GI Workshop in Shanghai Credit: Dr. Hanlong Liu
T-Shape Soil Mixing Credit: Dr. Songyu Liu
Thank You!
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