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By Wolfgang G. Brunner

In the far north of Uttar Pradesh Province in the Indian Himalayas, the 280 MW Dhauliganga hydroelectric power plant is under construction by National Hydroelectric Power Corporation (NHPC), a state- owned enterprise, and a joint venture of Kajima Corporation of Tokyo and Daewoo Corporation of Seoul. This project sets out to develop the lower section of the mountain cascade of the Dhauliganga River, a tributary of the Sarda River, with a 311 m gross head. The 1360 km2 mountainous catchment area is bounded in the north- east by the Chinese border and in the south- east by the Nepalese border. The dam project is located in a remote area north of the principal town of Darchula of the upper Sarda valley, which is one of the seismically most active regions of India. The 56 m high rock fill dam, which will be the first of its kind in India, is faced with concrete and has a 1 m thick, at its crown 270 m long and over 70 m deep cut- off wall of plastic concrete below its toe. The cut- off wall, with a total area of 7500 m2, is constructed by a combination of Bauer hydraulic grabs, assisted by chisels and a Bauer BC 40 cutter which enables the overlapping joint system to be installed, guarantees optimum verticality and enables the cut- off to be keyed into the bedrock formation.

Jan 1, 2004

By Jennifer Peirce Brandt

Project documents and the United States Army Corps of Engineers? permit for construction of the Stemmers Run Relief Wastewater Force Main across the Back River in Baltimore County, Maryland specified a minimal width, steel sheet pile cofferdam and a 12 feet wide, pile supported, timber decked, causeway trestle ? both approximately 1700 feet in length. Due to the impractical width of the causeway, the contractor desired to combine the cofferdam and the causeway structures in order to minimize wetland disturbance and maximize access for construction equipment. The resulting support structure was a steel sheet pile cofferdam, approximately 17 feet wide, internally braced, and capped with transverse timber deck mats to serve as the access and work trestle for the trench excavation, pipe bent construction, and trench backfill. Construction of this cofferdam/causeway progressed from the north shoreline toward the middle of the river. Then, working back toward the north shoreline, the contractor excavated, installed the 54 inch diameter pipe and H-pile support bents, and backfilled the trench in increments of approximately 60 linear feet. Excavation spoils from one section were used to backfill the preceding section. As the pipe installation progressed toward the north shore, the steel sheet piling and timber deck were removed. As sufficient sheet piling and deck mats were removed, the contractor began the process anew from the opposite shoreline using the reclaimed materials. The project was complicated by the presence of deep, very soft, weight of hammer, silts and organic clays and an unbalanced, hydrostatic head of 20.5 feet. In addition, concurrent pile driving, excavating, and backfilling in successive cofferdam sections required the use of heavy, long reach, hydraulic backhoes, and a 200 ton capacity crawler crane which controlled the design of the timber causeway deck and its supporting sheet piles.

Jan 1, 2008

By Yahia M. Al-Smadi

Effect of lateral loading against existing sheet pile wall and distribution of gravity loading due to various number of construction loading scenarios were studied. The objective of this effort was to determine the loading case that permits the contractor to utilize a 400 ton crane at the specified location with the existing limitation imposed on site. Staged analysis was determined as the methodology that will more accurately predict the exiting and additional stress due to the impose crane loading. A reliable and robust analysis (ANSYS) software was used to complete both 2D and 3D finite element model and analysis. Analysis model parameters such as material properties, non-linear behavior of the soil, and meshing are presented and discussed. At the conclusion specific range of crane operation and pick weights operating on existing concrete mat supported on top of an existing tunnel was reviewed and deemed acceptable.

Jan 1, 2010

By Brian McGlynn

There are many factors that can result in a site characterization being limited. For example, a client may undervalue the importance of a good geotechnical report, or an owner may feel that it would take too much time to perform an appropriate investigation among other reasons. For this project, neither was the case. The challenge was that the construction sequence of work required wick drains to accelerate the settlement of soil that had yet to be placed, resulting in the need to create a wick drain bid package based on unknown settlement parameters. This wick drain project took place in Long Beach, California, at the Long Beach Middle Harbor Re- development. For much of the past decade, the Port of Long Beach undertook a $1.5 billion redevelopment of two outdated terminals to create the Long Beach Container Terminal (LBCT). To achieve this goal, the existing terminals were demolished and the slip that serviced one of the older terminals was designed to be infilled to create the new area that would allow for the LBCT to manage 3.3 million TEUS (a commonly used freight term meaning twenty-foot equivalent unit) of cargo each year. Ultimately, the construction of the LBCT would be performed under multiple contracts to allow the new terminal to begin operation in a phased approach. Menard performed the wick drain installation under two out of three contracts, and this case history focuses on the challenges anticipated and faced under the second of these awarded contracts.

May 1, 2023

By Dempsey S. Thieman

The Kuparuk River Central Channel Bridge on the North Slope of Alaska provides critical access for oilfield service vehicles in the largest oilfield in the United States. The original sloped spill-through bridge abutments were protected by articulated concrete revetment. After 27 years of heavy service, ice impact, deep river scour, and high floods, the revetment required replacement. An OPEN CELL SHEET PILE® abutment was selected to replace the existing erosion protection and provide increased performance and structure life. Project engineers and contractors successfully addressed the challenges of low overhead sheet pile installation under the bridge, extremely heavy vehicle loads, and arctic winter construction conditions through innovative design and construction techniques. The project was successfully completed on schedule with minimal disruptions to critical bridge traffic. This paper provides a detailed discussion of the design and construction techniques utilized to address the challenges of the project, many of which could be adapted to other projects.

Jan 1, 2008

By Gianfranco Di Cicco

Seepage problems were recorded for more then 40 years at the Walter F. George lock and dam. In 2001 the Mobile district of The U.S. Army Corps of Engineers turned to the installation of a 200 feet deep cut-off in a final attempt to remedy the situation. The advertised design-built contract requested the installation of the cutoff wall in front of the concrete structure of the dam starting from 90 feet of water, cutting through a concrete lock structure, a submerged retaining wall and extending on both sides on the earthen embankments. This paper summarize the history of the project and the installation of the first recorded cut-off wall constructed under deep water, upstream to an existing dam structures and under an existing concrete lock. The technology used combined with the project's results may be considered a milestone in the marine foundation and the marine cut-off wall construction technology.

Jan 1, 2013

By Anne Lemnitzer

When a major storm system stalled over Western Europe last summer, it pro- duced the deadliest flood on European territory in the last two decades. Beyond record-setting rainfall over countries such as Luxembourg, Switzerland, France and the Netherlands from the storm's "Bernd" low pressure system, more than 230 people were killed in Germany and Belgium. The storm system also caused over an estimated $20 billion (€17.7 billion) of damage. A team from the Geotechnical Extreme Events Reconnaissance (GEER) Association, supported by the National Science Foundation, was mobilized to investigate the potential impacts of the widespread flooding in Germany, Belgium and the Netherlands. Members of the DFI Europe regional chapter closely collaborated with the U.S.-based GEER team and many other engineers and scientists in Europe to collect perishable data and study flooding effects and the event's resulting impacts on geostructures, such as bridges, retaining walls, dikes and embankments. This article features some of the vast information collected by the team, which has recently been published in a comprehensive reconnaissance report and made available for free at geerassociation.org. All data will also be accessible at the NEHRI DesignSafe Cl data repository.

Feb 1, 2022

By Silas C. Nichols

FHWA Interest is due to: ? An increase in successful projects in the U.S. private sector and in other countries ? Cost effective and more efficient in many circumstances ? Agency Priorities - FHWA "Vital Few" AASHTO TIG

Jan 1, 2005

By Bidjan Ghahreman

A total of 120 micropiles were constructed for foundations of a new selective catalytic reduction (SCR) unit in a coal-fired power plant east of Kansas City, Missouri. Construction was performed under restricted overhead conditions because of the existing facilities. The subsurface profile included about 70 feet of overburden composed of granular fill, stiff to very stiff cohesive material, medium dense sand, and very dense gravel. The bedrock was composed of alternating layers of shale and claystone (weak rock) and limestone (strong rock). It was decided that the bond zone would be entirely in the bedrock. The design rock profile along the bond zone was composed of 10 feet of shale and claystone underlain by 10 feet of limestone, which in turn was underlain by shale and claystone. To achieve the design compression and uplift capacities of 100 tons and 60 tons, respectively, a length of 23 feet was determined for the bond zone. Compression and uplift load tests were performed to verify the design. IBC-2000 elastic line, Decourt (1999) extrapolation, and Chin-Kondner extrapolation were used to interpret the load test results. The interpretation of load test data indicated that both compression and uplift capacities far exceeded the respective design loads. Spring constants of 397 tons per inch (T/in.) (in compression) and 290 T/in. (in uplift) were estimated from load tests at respective design loads. During the compression load test, no sign of creep was observed after the applied load was maintained at the design load (100 tons) for two hours.

Jan 1, 2009

By Brett K. Mainer

In the summer and fall of 2007, Drill Tech Drilling and Shoring, Inc. designed and built three 24-foot inside diameter shafts in Northern California using soil mix panels for support. The soil mixing was performed using the Bauer Cutter Soil Mix (CSM) method, by which rectangular soil mix panels up to 71 feet deep were arranged in an overlapping manner to form a 24-foot inside diameter circle. The shafts were then excavated to depths up to 51 feet. One of the shafts was a test shaft and used only the soil mix panels for support. The other two shafts were located immediately adjacent to the Mokelumne River and were used as access pits for a microtunnel drive under the river. These two shafts had wide flange beams embedded in the panels and were supported with several levels of ring steel placed during excavation. This project was the first use of the Bauer CSM method in the United States. The CSM method has been used extensively in Europe and Asia, but never for this application and never with this high a loading criteria due to water head and microtunnel reaction forces. Soil conditions at the river crossing shafts consisted of sands, gravels, and cobbles over top of sandstone and conglomerate bedrock ranging in strength up to 5,000 psi. Groundwater was within several feet of the surface. The shafts were successfully completed between October 2007 and January 2008, and the microtunnel was successfully completed in February 2008. This paper provides discussion regarding selection of the shoring type, structural design, the soil mixing method, and the mix designs. Shaft construction, shaft performance, and the capabilities of the CSM equipment are presented.

Jan 1, 2008

By Jim Cook

Arsenal Football Club required the development of a new home stadium in north London, subsequently named the Emirates Stadium. The proposed development comprised a 60,000 seat stadium, with associated facilities and a sports training centre. Described are the foundation solutions and piling construction techniques used, which take into consideration the potential impacts on existing above and below ground railway infrastructure and underground water structures. Methods used by the piling contractor to improve aspects associated with health, safety and quality are also described.

Jan 1, 2008

By Lawrence F. Johnsen

Six case histories are presented in which tall, slender high rises are supported on high capacity minicaissons. The recent development of a high strength rebar cage has resulted in compressive loads of up to 3400 kips on 24 inch diameter minicaissons. Provisions in the pending NYC building code will allow borehole video inspection in lieu of load testing. The ?new? technology results from the marriage of several well established methods: rotary duplex well drilling, high capacity micropiles and high capacity reinforced concrete building columns.

Jan 1, 2007

By Terence P. Holman

Micropiles are employed to retrofit existing foundations, including underpinning prior to future construction operations and resupport of existing structures that have experienced distortion and settlement. This paper presents analyses of the two case histories requiring the use of micropiles in these applications. The first case history involves micropiles used to resupport a settled pump station next to an excavation which had suffered basal failure and ground loss. A compression load test pile experienced plunging failure which, after analysis of the strain-gauge data acquired during the test, was attributable to a greater degree of disturbance to the subsoils beneath the site than anticipated. After construction of the micropiles around the pump chamber a synchronized jacking system was used to lift and right the 320 kip chamber structure, followed by resupporting it on the newly constructed piles. The second case history entails the use of micropiles for direct underpinning support of existing columns prior to a utility tunnel installation within an existing high-bay warehouse structure. The design constraint that most significantly affected the successful completion of this project was the desire to bond the new piles into the existing reinforced concrete foundations. As a result of the coring method through the footing, the ultimate bond stress measured during a pullout test was more than twice that assumed in the design. Monitoring of the underpinned columns during trench excavation indicated that the system performance was acceptable. These case histories reinforce the concept that lower capacity micropiles can provide a rapid means to underpin and retrofit existing structures.

Jan 1, 2007

By Todd Nottingham

Channel deepening of major ports is challenging designers to explore innovative solutions to ensure stability of bulkheads, such as for the Oakland Inner Harbor. This particular challenge was met with the use of the SPIN FIN® Tension Pile for restraint of an HZ combination wall along the Oakland Inner Harbor Shoreline in Oakland, California. A SPIN FIN pile is a pipe pile with welded plates at the pile tip that increase pile capacity. A brief history of the project will be provided as well as results of pile load tension tests, pile strain gauge, and wall deflection under construction loads. Tension pile load deflection results will be discussed with recommendations toward establishing deflection-based ultimate load criteria. A discussion of predicted wall loads and field observed wall loads will be provided.

Jan 1, 2008

By Douglas L. Scaggs

Driving piles in under water applications has become more common place over the past twenty years. Where only a water depth reachable with a follower or dewatered cofferdam was the rule in the past, newer technologies developed for the offshore oil and gas industry have made depths of even several thousand feet possible offering new possibilities in foundation design and installation. With the new technology, engineers can now more efficiently design structures by placing foundations optimally thereby reducing weight and cost of the overall structure.

Jan 1, 2013

By Alberto Carmona Rosell, Sri Ram Ramankutty

"The installation of Bored Piles and Diaphragm Wall under slurry using tremie raises quality concerns on the integrity of concrete. It is vital to understand the effects on concrete integrity during concrete pouring process. This paper intends to unveil to what extent the compressive strength of the concrete pour is affected in contact with drilling fluid still. Another important angle of analysis proves whether the inclusion of solids particles of un-hydrated fluid could have impact on the concrete compressive strength. The testing comparing the response of concrete compressive strength when drilling fluid is included into the concrete mix altering the water/cement ratio by 5%, 20% and 30%. Comparative results are analysed between two different hydrated slurries namely sodium activated Bentonite and 3rd generation synthetic polymer.1. INTRODUCTIONSoil stabilization is the base for a successful deep foundation execution. The G3 System Slurry developed by Ground Engineering Operations (GEO), with its third generation polymer, namely PolyMud®, is an innovative and unique alternative to the mineral based slurries for soil stabilization, enhancing the quality and integrity of the underground foundation structures. It optimises the production rate of work progress and cost as well. At the same time, PolyMud® slurry is proven to be environmentally friendly.Guaranteeing the maximum quality of the foundation elements according to the initial design is one of the most important objectives and a concern for the foundations contractors. In order to fulfil the project expectations in this aspect, any incident that could compromise the designed concrete integrity and capacity must be avoided.GEO, has carry out its own research regarding effects on the concrete compression results if drilling fluid intermixes with fresh concrete while pouring. To shed light in this regard, GEO, in collaboration with CML (Concrete Materials Laboratory) Sdn. Bhd., carried out empiric tests that analyse this particular event from different perspectives, bringing up the corresponding results that will be studied and commented in this article."

Jan 1, 2015

By Jesus Gomez, Mary Nodine

Rigid inclusions are widely used in the U.S. as a ground improvement tech- nique, particularly for industrial, low- rise and highway applications with poor subsurface conditions, where control of settlement is necessary. Rigid inclu- sions consist of grouted or concrete elements typically 12-24 in (305-610 mm) in diameter that may or may not be reinforced with a center bar. Typical soil conditions where rigid inclusions are feasible might consist of a surface layer of fill and natural, granular soil, followed by a stratum of soft silt or clay overlying a dense or stiff formation. Rigid inclusions are installed from the existing ground surface or suitable work platform, through the surface soils and through the soft, compressible layer, and into the deeper layer, which is less susceptible to compression- induced settlement. Typically, when used to support an extended area surcharge, the inclusions are installed in a rectangular or triangular pattern at regular spacings ranging from 5-12 ft (1.54 m), depending on a variety of factors. The rigid inclusion system is often capped with a load transfer platform (LTP), whose function is to direct a significant portion of the applied load toward the rigid inclu- sions. Additional load is transferred to the rigid inclusions through the upper fill soils above the compressible layer. The rigid inclusions transfer the applied load axially to their tips and into the deeper layer. In the U.S., rigid inclusions are mostly installed using displacement auger systems. The use of a dis- placement auger has significant advantages. It produces zero to near- zero spoils, which is an important environmental consideration. The

May 1, 2023

By John G. DiGenova

The Allwell Center Ice Arena at Plymouth State University, Plymouth, New Hampshire is located in the flood plain of the Pemigewasset River. To maintain the arena near the level of the surrounding area, foundation design required use of uplift elements to resist hydrostatic loads caused by frequent flood conditions. Soils beneath the arena consisted of very loose to medium dense alluvial deposits overlying thick glaciolacustrine deposits. Bedrock was encountered at depths of 115 feet (35 m) or more. A mat foundation with a sealed building system was developed for the arena to guard against flood events. Several alternatives were investigated to provide uplift capacity for the mat foundation, including the Rammed Aggregate Pier® (RAP) system, driven precast-prestressed concrete piles, driven H-piles, and deep drilled soil/rock anchors. Evaluations indicated that the most cost effective uplift solution was a tension RAP system that developed uplift resistance in the shallow alluvial deposits. A total of 344 55-kip (245-kN) capacity RAP elements were required for the project. The RAPs were designed to resist tensile loads using threaded steel bars. Dual corrosion resistance was provided to the uplift elements by including sacrificial steel and galvanizing the oversized bars and connection plates. A pre-construction test program was conducted on RAP elements drilled to a depth of approximately 25 feet (7.6 m) and installed using various shaft construction procedures and materials. Ten test piers were constructed and six were tested to verify that the piers could resist 200 percent of the design load with measured deflections of less than 1 inch (25 mm). The RAP system also provided improved bearing conditions for the perimeter wall and mat foundations by densifying and stiffening the upper alluvial soils.

Jan 1, 2011

By X. M. Wu

The paper describes four different types of support for deep excavations, which are currently used in China. Local experiences were illustrated by presenting case histories for each type of support. For braced excavation in soft clays in Shanghai, the earth pressure against bracings were found to be in conformity with the trapizoidal estimation given by Terzaghi and Peck (1967). For tie-back support of excavations in Beijing and Shengyang, earth pressures were found to be much less than those predicted by ordinary rules. In the construction of a mining shaft in coarse sand below ground water level, high pressure jet grouting has been successfully used to form a circular impervious lining of the shaft. As an effective anti-slide measure, large diameter reinforced concrete piles constructed by open shaft method have been widely used with success.

Jan 1, 2010

By Nathan A. Ingraffea

The use of steel sheet pile walls and drilled shaft foundation elements to enable up-down construction methods has been used successfully on recent high-rise structures with multi-story below grade parking. The John Ross Tower and The 3720 Tower in Portland, Oregon each make use of this system and are discussed in-depth. Up-Down construction involves the simultaneous construction of the building levels above and below grade instead of the standard construction technique of excavating and shoring the below grade construction before being able to build upward from the base of the excavation. Advantages of the up-down system include a shortened overall construction schedule, permanent basement walls that double as the temporary shoring walls, elimination of the typical continuous wall footing or grade beam at the building perimeter, increased use of recycled material (steel) while maintaining an overall decrease in total materials, elimination of wall forming costs, decreases in forming costs for slabs, decreases in waterproofing costs for walls and elimination of pile caps and/or footings for the building columns. Lessons learned during the construction of both buildings include the need for more extensive geotechnical boring information, descriptive sheet pile and drilled shaft specifications, a clear understanding from the design team on finished appearance of sheet pile and shafts, and careful consideration of the connection between both slabs and the sheet pile wall and slabs and drilled shafts.

Jan 1, 2008