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By H. Shiri

Iran's largest natural gas field is South Pars, geologically an extension of Qatar's 900-Tcf North Field. South Pars was first identified in 1988 and originally appraised at 128 Tcf in the early 1990s. This Field contains 38.6 % of the gas resources of Iran and is regarded as the largest offshore gas field in the world. Offshore geotechnical site investigations are one of the key activities of upstream fields operators to supply the EPC contractors with the required results for designing approaches of offshore complexes. In the mean time a lot of marine site investigations have been carried into execution within the phases of South Pars development. The authors are currently trying to create the fundamentals of investigating the small- and large-scale spatial variability of the South Pars Gas Field in Persian Gulf/ IRAN. Part of this investigation is the providing of an extensive data base of the offshore geotechnical properties of South Pars. Such a data base, will enable a model to be developed of the large-scale variability of these properties. In addition, this data set will provide a data whereby general trends to be established, as well as, providing relationships between geotechnical parameters and spatial parameters utilizing probabilistic and data mining methods like ANN (Artificial Neural Network) in Geotechnical Engineering.

Jan 1, 2006

By I. K. Ozaydin

Analysis of piles groups loaded with large bending moments and both vertical and batter piles can be best performed by matrix analysis. In this paper, a case history about a tall marine control tower is presented. The soil conditions at the site and the results of the computer analysis of the piled foundation are summarized. It is shown that the pile loads are indeed less than the allowable load for a single pile. Pile head loads and moments are used in the analysis of the raft foundation.

Jan 1, 2010

By Bernardo J. Jiménez, Harlem Lora, Roberto Acosta Mora

Circunvalacion Norte project is currently the most important infrastructure project in Costa Rica. It is the last segment of the urban perimeter highway. Site investigation of local geotechnical conditions were studied by SPT, CPT, pressuremeter tests and boreholes. A static load test was executed as a proof test with an associated ultimate resistance of 12056 kN (2710 kips). Drilled shaft design was done using PMT tests and axial nominal resistance varied between 4000 kN (900 kips) and 6000 kN (1350 kips). A total of 416 drilled shafts were constructed in 15 months with drill performance of 32 m/day (105 ft/day). Drilled shaft lengths varied between 4,0 (13 ft) m and 40,0 m (130 ft). Selfconsolidating concrete was used to achieve an adequate workability even in high densities rebar cages. Several site conditions proved the importance for maintenance of the working platform, predrilling of rock sockets and having spare parts to avoid increase in project’s cost. New procedures were taken to prevent concrete segregation on excavations near underground water flow. Monitoring the quality of the shafts from CSL test showed less than 3% of the shafts presented a considerable anomaly, which proved that the adopted construction method and materials were adequate. For the concrete anomalies, successful remediation was performed by means of grout at the base of the shaft with two different types of drilling methodology depending on the concrete anomaly.

By Francis B. Gularte

The Dalles Dam is located 192 miles upstream from the Columbia River?s mouth. As part of an effort to increase survival rates for young salmon migrating downstream to the Pacific Ocean, a river spillwall was constructed to guide the young salmon into the thalway and out of the reach of predators. The spillwall consisted of 43 large precast concrete cells constructed onsite. The 120-ton cells are positioned on the bedrock riverbed to form the 830-foot-long spillwall. Large capacity post-tensioned strand anchors extend through ducts in the precast units, anchoring the wall to the basalt. One hundred seventy-eight tie-down anchors consisting of 30, 32, or 40 strands were installed and post-tensioned to secure the cells. The logistic and technical challenges presented by positioning, installing, and stressing the precast cells in the tailrace of a large dam required a high level of cooperation and planning between the owner, general contractor, subcontractors, and suppliers in order to finish the project within the allotted in-water work windows to minimize impacts on seasonal salmon migration.

Jan 1, 2010

By David S. Graham, Joseph D. Bailey, Paul J. Axtell, Michael K. Muchard

"Two instrumented test piles were simultaneously subjected to a static lateral load test by jacking the piles apart. One of the piles was loaded in axial compression via kentledge during the lateral load test. Both piles were constructed in an identical manner. These piles were constructed and tested as part of a construction-phase load test program for a floodwall improvement project along the Missouri River in Kansas City, Kansas. Details of the subsurface conditions, drilled pile construction, instrumentation, and load testing procedures are described. Data collected during testing of the piles are presented and compared. Potential effects of the axial compressive load related to observed differences in pile lateral response are discussed.INTRODUCTIONTwo instrumented test piles were simultaneously subjected to a static lateral load with one of the piles also subject to a combined axial load during testing. The load test program was part of a floodwall improvement project in Kansas City, Kansas. Known as the BPU floodwall, the floodwall runs along the south bank of the Missouri River at a Kansas City Board of Public Utilities power generation and water treatment facility. The project location is shown in Fig. 1.Drilled, 2-ft (610-mm) diameter piles were designated by the designer, the U.S. Army Corps of Engineers (COE), as the foundation type for supporting extended floodwall footings. The drilled piles are fully cased, cast-in-place concrete, reinforced with a steel 12x74 (310x110) H-pile. In order to test soil lateral response and pile structural response under combined loading, the COE required that both a lateral test and combined lateral and axial test pile be constructed and tested. In order to most efficiently test both piles and to allow for simpler comparison, the two piles were simultaneously laterally loaded by jacking the piles apart, applying a maximum lateral load of 195 kips (867 kN). A constant axial load was applied to the combined test pile by kentledge prior to lateral loading and was maintained for the duration of the lateral load test. The total weight of the kentledge was 61.5 kips (274 kN). Fig. 2 shows the test setup."

Jan 1, 2017

By Daniel Levacher

Pile load tests in site require extensive means of action and time. To get outstanding tests, the environmental test conditions must be perfectly known and acceptable. They concern the support installation, the loading, the access and instrumentation site conditions and the economical aspects. In particular cases as offshore areas, the load tests are not feasible. Moreover the variability of soil characteristics limits the interpretation results at the considered tested site. The use of centrifuge modellling offers an other way to study the loaded pile behaviours. Centrifuge tests lead to parametric approaches which constitute for geotechnical engineers an important data base tor recommendations and design codes. To accurately simulate pile behaviours by checking similitude laws linked to the studied problems, the installation of model-piles must be also representative of the in-situ piles. Driven piles account for a large part of the piles installed through the world, mainly for offshore or harbour constructions. So, to explore driven pile problems by centrifuge tests, miniature pile driving hammers must be developed and tested under macro-gravities. The paper describes two types of these ones in details. They are commonly used at the centrifuge centre of the Laboratoire Central des Ponts et Chaussées - (LCPC) - [Réf. 1] for different deep foundations researches. Performances and limitations are given for both miniature pile drivers and some results from their use are presented to illustrate the suitability of these apparatus.

Jan 1, 1996

By Rajesh A. Vaidya

A large scale piling work is undertaken in India for an important fast track industrial project. Thousands of solid square precast concrete piles are driven to depths of around 50m. Soils encountered are of alluvial origin with very soft clays varying in thickness from 10 to 18m at the top followed by medium dense to dense and occasionally very dense sand, stiff clay and finally dense to very dense sand layer as the founding layer. Recent site grading with around 4 metres thick hydraulically filled river sand necessitated driving the piles to the bottom sand layer to avoid problems on account of negative skin friction and to achieve optimum pile capacity. A process approach suggested by Bell et al (2002) to promote better understanding of the pile behaviour, pile capacity, and parameters assumed at design stage for static capacity and for wave equation analysis is followed with an aim to bring in effective economy in terms of pile length and pile installation speed. Soil investigation work is also undertaken in stages to cut down pile wastage. A judicious combination of PDA and static pile load tests is followed. Pile Driving Analyser (PDA) tests at end of driving and also at various stages of recovery of pile capacity are carried out to understand the pore pressure dissipation phenomenon. The paper attempts to present some of the valuable experiences that would go to establish precast pile as a very effective alternative to driven cast-in-situ piles and bored piles which are very common in this part of the world despite their limitations in terms of economy, speed and certain geotechnical aspects.

Jan 1, 2007

"Boston’s Central Artery passes beneath nine active railroad tracks carrying commuter and Amtrak trains into South Station, the City's busiest rail terminal. These railroad operations had to remain in service throughout the construction of the “Big Dig”. The solution was to jack the tunnel under the tracks, rather than build the tunnel by more conventional means.Jacking of utility pipes is fairly common, but jacking boxes as big as a highway had never been done in North America, until the Big Dig came along.Soil freezing was decided upon as a means of stabilizing the soil under the tracks. This allows the tunnels to be jacked into place without soil caving when the soil is excavated at the leading face of the advancing tunnel boxes. Hundreds of pipes were driven into the ground between the tracks. Inside the steel pipes were smaller plastic pipes. A freezing plant near the railroad tracks pumped refrigerated brine into the inner plastic pipes. The brine ran out the bottom of the inner pipe, flowed up to the top inside the outer pipe, and was re-circulated to the freezing plant and back again into the ground. Over several weeks the circulating brine drew the heat out of the soil little by little, and froze the ground outward from the pipes. Soil FreezingThe plan required the construction of jacking pits in which the tunnel boxes could be constructed, and from which they could be jacked forward to their final locations, as described in the accompanying article. Once the jacking pit was built and the tunnel box constructed inside the pit, crews made an opening in the headwall of the pit to allow passage of the tunnel sections, excavated about three feet of the frozen soil, pushed the tunnel box ahead, and repeated the procedure again and again."

Jan 1, 2003

By Masaki Kitazume

Five papers were presented orally to the topics of Jet Grouting and Deep Mixing. The session was started with a brief introduction by the moderators. Following the oral presentation, floor discussions were directed by the moderators. A brief introduction of each of the oral presentations is provided before each discussion.

Feb 10, 2003

By Filippo Mira-Cattò, Andrea M. R. Pettinaroli, Elena Rovetto

"The construction of Powisle station of Metro Warsaw Line 2, in Poland, required the execution of two shafts next to an urban road tunnel adjacent to the Vistula River. The shafts were linked by three conventionally mined tunnels to be excavated 10 m below the water table level, into an upper sandy and sandy silty layer and a lower stiff clayey stratum. After a failed dig attempt under the protection of jet grouting and forepoling, it was decided to deal with the tunnels excavation problem by using the ground freezing technique as a temporary, non-polluting geotechnical treatment, keeping in service the upper road tunnel. The planning of the activities and the executive phases had a significant importance for the success of the work. For work scheduling reasons the mixed system was adopted, i.e. using both the liquid nitrogen system and the brine freezing method. The freezing process management, with a real time evaluation of the soil temperature measured by thermometric strings and an accurate monitoring of the overlying road tunnel structure, allowed the tunnel excavation and lining stages to be performed under difficult conditions, without water leaking from the frozen ground shell, within the expected times and saving extra costs.INTRODUCTIONThe new Underground Line 2 in Warsaw connects the eastern and western part of the town. One of the most critical interferences was the under passing of the Vistula river and of the Wislostrada motorway tunnel, a very congested motorway along the western bank of the river, with the construction of the new station Powisle. The construction of the station required the excavation of two shafts, using the top-down system with the creation of intermediate slabs while deepening the excavation.The shafts were used for the extraction of four Tunnel Boring Machines (TBMs), two approaching from the Vistula river side (east-side) and two approaching from downtown (west-side); in order to connect the two shafts was foreseen the realization of three tunnels, two for the underground lines and the central one for the exchanging passenger platform. These tunnels were underpassing the “Wislostrada Road Tunnel” and interfered with this tunnel foundation, which consisted of diaphragm walls (DW), the “barrettes” (Figure 1).Due to the variable geological conditions at the site, the first excavation stage, with a temporary underground support constructed of horizontal jet grouting columns and forepoling, caused the North tunnel face failure, that required an immediate filling of the empty cavities with lean mix concrete under the Wislostrada tunnel slabs. Thereafter, the recovering attempt with the grout injections could not be completed because of the development of heaves induced on the tunnel structures (Bringiotti et al. 2016). In those conditions the tunnel excavation with traditional technologies appeared to be very problematic, with high risk for the structural safety of the Wislostrada tunnel. This would have meant longer duration for the works and higher costs for the General Contractor as well as for the city Council."

Jan 1, 2015

By Qingwei Joshua Ong

Tension piles, also known as uplift or anchor piles, are necessary to resist uplift forces that might cause structural distress. In excavation projects, most uplift forces are developed because of hydrostatic pressures, and so tension piles are subjected to a great deal of tensile forces. Most current methods of design for tension piles completely neglect the tensile strength contribution of concrete, relying only on the steel members to carry the tensile stresses, resulting in an overly conservative design. The stressstrain behavior of the composite material of concrete and steel must be considered for a realistic simulation of tension piles. This paper will examine a case on a tension bored pile in typical soft clay to demonstrate the importance of considering the tension strength and tension softening of the concrete.

Nov 1, 2022

By David J. Puller

As part of the value engineering process on a major Design Build highway project, instrumented trial pile load tests were used to achieve savings in cost and time on the foundations for a major river crossing. Two trial piles were tested close to failure load at 25MN. Following the interpretation of the pile load test results which included the determination of the ultimate shaft and base capacity, the mobilisation of the shaft and base resistance with pile displacement, and correlations with vertical effective stress and SPT profile, a revised design methodology was proposed. A 25% enhancement on commonly assumed ultimate shaft friction in Chalk was adopted. In addition a significant reduction in the Factor of Safety on end-bearing capacity generally used was also implemented. The revised design resulted in a significant cost and time saving on the piling operation with the pile length reduced by up to 6m (approx. 20%) for the river piers.

Jan 1, 2002

By W. G. K. Fleming

The codification of foundation design and construction is a subject of extensive discussion in Europe and all current code proposals are based on limit state partial factoring. For simplicity, it is claimed, simplified forms of Partial Factor use are presently being advocated but, if this is the direction which codes are to follow, then it is preferable in this age of computer technology that a true system should be adopted rather than a simplification. A philosophically satisfactory method can readily be found which can fulfilcurrent requirements and it is better that such a method should be adopted from the beginning rather than later to find it necessary to make important alterations and amendments.

Jan 1, 1996

By Jorj O. Osterberg

This paper is for presentation at the 14th Annual Members Conference of the Deep Foundations Institute held at the Hyatt Regency Hotel, Baltimore Maryland on October 10, 1989. This is an introductory presentation of a one hour symposium on the applications of a new testing device. This paper discusses how the device works and its uses. Papers following this describe: - How the cell is constructed and calibrated - Two projects on which the device was used on long driven piles to determine the frictional capacity - A bridge project on which the device was used on an instrumented test drilled shaft and a working drilled shaft

Jan 1, 1989

? Hollow Stem Auger ? Drill Bits ? Leads/Torque Arm ? Hydraulic Gearbox ? Hydraulic Power Unit ? Grout Pump ? Crawler Crane

Jan 1, 1998

By Jiun-Yih Chen

Pile load tests are regularly used to verify pile capacities. Sometimes, they are used to optimize pile designs. This paper presents a case study based on a real project, in which the information obtained from load tests during construction was used to shorten the design pile lengths without a formal decision analysis. In this study, a simple probabilistic model was used to assess the probabilities of failure based on design information. The Bayesian approach was used to update the probabilities given the additional information from load tests. These probabilities were then used in a formal decision analysis to determine the optimal pile lengths based on design information and based on the additional information from load tests. The optimal pile lengths are different from those implemented in the project without a formal decision analysis. The value of the formal decision analysis is illustrated by its ability to optimize the pile length in a transparent and defendable way.

Jan 1, 2009

By Manfred Schoepf

"Construction projects using the most advanced technologies and organizational structures demand intelligent construction machinery. In this process, automation technology plays an increasingly important role. Many components used in the automatic control of machine components are being taken for granted to such an extent that operators are often even unaware of their existence. Innovations in micro-electronics, such as process computers, programmable logic controllers (PLC) or intelligent sensor systems, have by now found their way into construction machinery. Construction machines are indeed becoming ever more intelligent. Key electronic applications in foundation engineering machines can be summarized into the following main categories:- Data acquisition- Online monitoring of the equipment status- Remote data transfer- Satellite-based Navigation System for Positioning and Documentation- Process controlData acquisitionThis includes machine-specific operating data, such as engine speed or operating temperature, operating hours, display of fuel consumption, but also the acquisition of process-specific data, such as pile depth, pile inclination or slurry volume.Monitoring the equipment status onlineAn extremely important aspect is the acquisition of fault data. In conjunction with available remote data transfer systems, malfunctions can now be searched and diagnosed by specialists anywhere in the world to provide assistance to the site personnel.Remote data transfer - “Anywhere, from everywhere”All previously referred to parameters can be stored on appropriate storage media inside the machine. The customer also gets a worldwide, safe access via an internet browser to check the current status of the equipment, anytime, anywhere.All data can be saved on a secured web server for documentation and further analysis. The internet connection of the equipment through a special module (DTR Module) additionally allows the user to operate a local, password-saved WLAN hot spot at the construction site and exchange data between equipment, tablet and internet.The web based system, which is named “WEB-BGM Equipment Management” in the Bauer Group, can do much more than only communicating with one machine."

Jan 1, 2015

By Shoichi Tsukuni, Akihiko Uchida, Kazuo Konishi

"In order to investigate the effect of grid-form deep mixing walls as a countermeasure for liquefaction damage to roads and private houses in Urayasu, Japan, three dynamic centrifuge model tests were conducted. Urayasu is located in the Tokyo Bay area, and private houses in the city incurred severe damage due to liquefaction during the 2011 Tohoku earthquake. In grid-form deep mixing walls design, the distance between grid-form walls is critical to prevent liquefaction. This study clarifies the relationship between the settlement of private houses and the distance between grid-form walls under the conditions that exist in Urayasu.INTRODUCTIONMany private houses in Urayasu, Japan suffered severe damages due to liquefaction during the 2011 Tohoku earthquake (Photograph 1). Fig. 1 shows the location of Urayasu and the maximum acceleration of the observed seismic waves in the Tokyo Bay area. At Urayasu, the duration of the seismic waves (hereafter called the Urayasu Wave) was about 2 min. The maximum acceleration was 1.57 m/s2 (Fig. 2), which is relatively small. The damages occurred in the land reclamation areas that consist of loose sand with an SPT-N value less than 10.To prevent liquefaction in future, it is necessary to adopt suitable countermeasures in the areas where many private houses suffered severe damages. Grid-form deep mixing walls are one such countermeasure. Fig. 3 and Photograph 2 show grid-form deep mixing walls. Walls are constructed using the deep cement mixing method. Fig. 4 shows a plane view of planned grid-form deep mixing walls for roads and existing private houses in Urayasu."

Jan 1, 2015

By Tim Siegel, III Fondren, Billy Camp

"INTRODUCTIONThe new $650 million power block at Santee Cooper’s Cross Generating Station in Cross, South Carolina is being constructed on driven pre-stressed concrete (PSC) piles. S&ME, as geotechnical subconsultant to Parsons Energy and Chemical Group, was responsible for pile analysis and design to meet the site’s geotechnical and seismic challenges. Selection, analysis and design of the PSC piles included consideration of the following:• Column and equipment support loads ranging up to 500 to 1000 kips (2224 to 4448 kN).• Incorporation of the 2000 International Building Code seismic provisions.• A thick upper soft clay and loose, liquefiable sand.• Potential for karst-related features in the calcareous Santee Limestone.GEOTECHNICAL CHARACTERIZATIONThe near-surface site geology consists of (in order of increasing depth): (1) Pleistocene sediments, (2) the Santee Limestone (considered part of the Orangeburg Group) of Eocene age, and (3) the Black Mingo Formation of the Eocene/Paleocene age (refer to the shear-wave profile in Figure 4). Pleistocene clays and silts are generally soft and will settle significantly if subjected to loading by heavy grade-supported structures while the interbedded sands are generally loose. Where submerged below the shallow groundwater table, the sands were determined to be liquefiable during a strong earthquake.The Santee Limestone is a nearly white to yellow fossiliferous and partly glauconitic rock consisting chiefly of calcium carbonate. Observations of the rock core samples from the site indicate that it can range from hard crystalline limestone (primarily in thin layers) to a lightly cemented sand. In terms of rock strength, the Santee Limestone is generally very soft to soft, depending on the cementation and other depositional characteristics."

Jan 1, 2004

By Antonio Zechini, Giuseppe Iorio, Massimo Grisolia

"The new C Line of the Rome Metro runs northwest to southeast across the city center, with 30 new stations and a total length of more than 15.5 mi (25 km). Due to the presence of a dense urban environment, the selected solution for the construction of the stations consists of a cutand- cover excavation, which is retained by multipropped diaphragm walls to minimize settlement and prevent damage to the nearby structures. The bottom of the excavation of the underground stations are about 82 ft to 98 ft (25 m to 30 m) below ground surface, and about 66 ft to 82 ft (20 m to 25 m) below the groundwater table. To ensure dry conditions and to prevent hydraulic base heave instability, deep well systems were designed and used to lower groundwater level and piezometric head during excavation. The dewatering field tests showed how the local stratigraphy strongly affects the dewatering efficiency. Finite element modeling (FEM) of steady state filtration were used to compare the soil permeability with Lefranc in-situ test results and to verify the efficiency of the grouted plugs. The geological sequence along the new C Line consists of a very heterogeneously layered deposit. The base deposit of stiff overconsolidated clay (“APL,” Pliocene age) is overlain by fluvio-palustrine very dense sandy gravels (“SG,” Pleistocene age), which are then overlain by medium stiff clayey silts or dense sandy silts (“AR” or “ST,” Paleotevere units). These deposits are overlain by covered by pyroclastic volcanic soils, tuff, silty sand and sandy silt (Middle to Upper Pleistocene) deriving from the Colli Albani apparatus. A layer of made ground (“R”) of varying thickness covers the stratigraphic sequence and the natural soil profile everywhere.The local hydrogeological framework is very complex and characterized by a double groundwater system. The upper main aquifer is mainly represented by the “pozzolane sequences” (“PR/PN”), while the lower aquifer consists of a deposit of sandy gravel (“SG,” Pleistocene), which is underlain by marine claystone bedrock (“APL,” Pliocene). The pyroclastic deposits (e.g., pozzolane, lithoid and pseudolithoid tuff and clayely tuff) show large variations in permeability due to porosity, compaction processes, sealing and secondary fracturing. Permeability values for each soil type were determined using Lefranc tests at variable head and using pumping tests. The Lefranc tests indicated a wide range of permeability."

Jan 1, 2017