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By Marcus Daubner

This paper explains how BAUER Spezialtiefbau GmbH uses digital methods on projects - starting from work preparation to completion of works. More precisely, the advantages of BIM-based planning during work preparation and the automated and structured data management - both machine production data and the manually recorded quality-relevant reports - during execution phase are displayed. In this context, the benefit of the digital twin to optimize processes, to reduce defect costs, for a more effective reporting sys-tem, and the further usage of as-built information in the BIM or GIS process is described.

Sep 1, 2022

By Karen Dawson

Pressure-grouted helical piles support a new seven-story homeless housing center in the Coney Island neighborhood of Brooklyn, New York. The project team instrumented and statically load tested piles to as much as 1,000 kips (4.4 MN) in advance of construction to obtain the approval of the New York City Building Code officials and to verify the design. Use of pressure-grouted helical piles required additional design effort and time risk because of New York City's Construction Code Determination (CCD1) process, which is required for non- standard deep foundation types. Despite

May 1, 2022

By A. Ghorbani

The analysis of Combined Pile Raft Foundation (CPRF) is very complex due to involved interactions among components of CPRF system. Many researchers made efforts to develop sufficient methods including three dimensional finite element methods to compute these interactions. Since there are some restrictions and complexity in previous methods, in present study a new approach based on three dimensional finite difference methods is implemented to overcome some of these restrictions. The total and differential settlements of a centrifuge case study are computed using different numerical methods to show the performance of present numerical approach.

Jan 1, 2007

By Dan A. Brown, Rich A. Lamb, Paul J. Axtell

"Over the last 10 years, the Minnesota Department of Transportation (Mn/DOT) has had a very active program of replacing many major bridges, large structures spanning the Mississippi River. The deep foundations for these new structures include both drilled shafts and large diameter open-ended driven steel pipe piles. Most of these projects included load tests, both axial and lateral.The geology of this area of Minnesota includes some interesting foundation challenges, including highly organic and compressible very soft silts and clays to very dense sand and gravel overlying sedimentary bedrock. In some cases scour requires embedment into rock, and the bedrock formations may range from very soft sandstone to very hard dolostone. Artesian groundwater conditions can sometimes complicate drilled shaft construction, but the rock is otherwise very favorable for drilled shafts. Experience with the open-ended driven steel pipe piles (typically 42 and 48 in, 1.07 and 1.2 m diameter) suggest that these piles most often penetrate even dense granular materials to achieve bearing on rock. Experiences with drilled shafts socketed into the soft sandstones demonstrate that these rocks provide very favorable conditions for drilled shafts, so long as suitable construction practices are followed. Here we present several recent case histories regarding the foundation design and construction of major bridge projects in the vicinity of Minneapolis, Minn., including the Wakota Bridge, the I-35W replacement, the Lafayette Bridge, the Hastings Bridge and the St. Croix Bridge. Some lessons learned from construction and load testing of both types of foundations are described along with implications for design in similar soil and rock conditions."

Jan 1, 2013

By Matthew D. Marks

"The Sacramento Area Flood Control Agency initiated the Natomas Levee Improvement Program in 2006 which would bring the entire 42 mile Natomas Basin perimeter levee system into compliance with applicable Federal and State standards for levee protecting urban areas. The soil-bentonite slurry cutoff has been utilized as the primary construction method for addressing the under seepage deficiencies. To date, a combined total of over 4,500,000 square feet of slurry cutoff wall have been constructed utilizing excavation methods to a maximum depth of 75 feet and deep soil mixing methods to a depth of 90 feet. The construction of these cutoff walls has required the use of newly designed and custom built long boom and stick attachments for large hydraulic excavators and additional resource will be required to complete future phases. Key components of the NLIP program have included advancements in the development of soil-bentonite backfill mix designs, specified ranges on the soil backfill gradation to address concerns of long term consolidation of the backfill material, evaluation of the trench slurry filtrate loss with regard to cutoff wall acceptance, maintenance high slurry densities to provide greater trench stability, and continued development of backfill mixing procedures.IntroductionThe Natomas Levee Improvement Program (NLIP) was initiated by the Sacramento Flood Control Agency (SAFCA) in 2006. The long term objective of the NLIP is to provide 200-year level flood protection to the basin. To date, approximately 21 of the 42 mile Natomas Basin perimeter levee system has been completed, totaling over $100,000,000 in construction contracts, of which slurry cutoff walls make up approximately $25,000,000. Other construction elements include excavation and removal of unsuitable levee materials, raising or widening existing levees, construction of landside seepage berms, drainage canals, and miscellaneous structures.Although each construction phase of the NLIP includes various construction elements of levee restoration program, the slurry cutoff wall is the primary construction element for addressing the under seepage deficiencies. To date, approximately 4,500,000 square feet of slurry cutoff walls have been installed using excavation and deep soil mixing (DSM) methods. This includes approximately 2,000,000 square feet of slurry cutoff wall along 5 miles of the NCC South Levee and 2,500,000 square feet of slurry cutoff wall along 16 miles of the Sacramento River East Levee (SREL). The work has been completed under 8 separate contracts, through SAFCA, and performed between September 2007 and December 2012. A summary of the contract phases and associated cutoff wall square footage is provided in Table 1. Most of the work has been performed within the seasonal dry weather period in the Sacramento valley, which occurs between April and October. This has required much of the work to be performed on an aggressive construction schedule, year after year."

Jan 1, 2017

By Takashi Enomoto

"The cement deep mixing (CDM) method has a wide range of applications, both on land and at sea. This paper describes the features of the equipment on CDM vessels engaged in maritime construction in Japan: the DCM No. 3 barge, the DCM No. 6 barge, and the DCM No. 8 barge. The DCM No. 3 barge is a large vessel with a mixing area of 5.7 m2. The design of the elevator of the deep mixing unit on the DCM No.3 barge enables us to conduct deep underground/ sea operations. This enables us to conduct mixing at depths of up to 52.6 m below the seabed and up to 70.5 m from the water surface. Additionally, since the tower is installed on the center of the barge, it has excellent stability. The DCM No. 6 barge and DCM No. 8 barge are mid-sized vessels with a mixing area of 4.6 m2. The DCM No. 6 barge was fitted in 2013 with energy conservation equipment and upgraded to an environment-friendly CDM barge. The energy saving upgrade used electric power, instead of hydraulic power, by inverter controlled alternating current motor for both mixing unit and main hoisting winch. This enables the using on effective use of regenerative power when the deep mixing unit is lowered. A feature of the DCM No. 8 barge is that it has an inclinable tower located at the bow section for elevating the deep cement mixing unit. Since the tower can be greatly inclined, the hull has a lower center of gravity and greater stability when the vessel turns. This also allows the vessel to pass below bridges and simplifies cruise preparations, outfitting and dismantling work.INTRODUCTIONThe cement deep mixing method (CDM method) involves mixing and stirring a cement-based solidifier into soft ground to rapidly bring the ground to the desired firmness. This method is used to suppress ground shear deformation, increase strength, increase slip resistance, and mitigate liquefaction and subsidence. It has been recently used in Japan in the construction of revetments at controlled waste disposal sites, both to boost the strength of the seabed and to prevent the seepage of waste matter and other pollutants. Undertaking CDM construction work at sea requires specially constructed marine construction CDM vessels. Since CDM construction at sea entails many more restrictions on working conditions than construction on land, the vessels themselves sometimes need to be modified. This paper will describe 1) the remodeling of the turrets and mixing machinery for mixing to great depths in deep water (DCM No. 3 barge with eight axes); 2) the upgraded of equipment on board CDM vessels after accounting for environmental considerations (DCM No. 6 barge with four axes); and 3) the use of a inclinable tower (DCM No. 8 barge with four axes)."

Jan 1, 2015

By Brian W. Wilson

A case study is presented that describes the design and implementation of a combined blast densification and deep dynamic compaction program which was undertaken to improve the foundation soils for a proposed tailings dam raise in Ontario, Canada. Based on the results of the geotechnical investigation it was determined that the foundation of the dam would be situated on tailings of both variable thickness and density, much of which would be susceptible to liquefaction under the design earthquake for the region and type of facility. Blast densification trials were completed by the owner and the results of these made available to prospective tenderers in response to a call for a fixed price contract for the design and implementation of a densification program for approximately 800,000 m3 of foundation tailings. The variation in tailings gradation and the impacts of such on the ground improvement program are discussed, as are details of both the additional blast densification field trials completed by the contractor, and the selected blast pattern and explosive charging used for production blasting. The applicability of the various ground improvement techniques to the actual conditions encountered, and the results obtained are also discussed.

Jan 1, 2010

By Mauricio Coto

Three bidirectional static load tests (BDSLT) were executed on bored concrete piles, as part of the permanent foundations for two buildings sites located at the Sabana, San Jose, Costa Rica, separated at a relatively short distance of about 1 km. Unit skin friction values obtained for both sites, principally for the “Lahar” layer show that in general, friction pile capacity from the tests is higher than anticipated per static calculations from soil borings geotechnical parameters correlations. Results from the tests were also compared with dynamic load tests (DLT) executed at other two sites in the surrounding area, and with a Finite Element (FE) Analysis that model soil-pile interaction for one of the projects. On the other side, some construction issues were detected on one of the sites, which negatively affected the end bearing capacity, but being that pile friction was higher than anticipated, the required overall pile capacity was accomplished. The BDSLTs results of these tests help to better understand the geotechnical behavior of the soil layers in the Sabana. Moreover, they also show that is possible to optimize the design and construction of other bored pile supported buildings and structures on the zone.

Pier, well cap and steining junction is a complicated 3-d re-ion. The prevalent design procedure for the pier, well cap and steining in isolated manner is not rational. In absence of an integrated approach for design of the junction structure, the well cap is designed uneconomical and at the same time pier and steining are left relatively unsafe. Strut-and-Tie Model based design is a simple solution to this problem. An example illustrating design of the junction structure using STM is presented. On comparison of the outcomes of the STM based design with the prevalent design, the following anomalies are found: i) For smooth flow of forces, length of pier at its base should preferably be made equal to the outer well diameter, ii) STM based design for the pier is more rational, economical and safe. iii) Due to presence of hoop stress, as indicated by the STM, the steining concrete in a depth of p times outer diameter of the well from the well cap level should be limited to M15 grade, iv) STM based design for the steining is more rational, economical and safe.

Jan 1, 1996

By Charles Winter

The Ohio Department of Transpor- tation's (ODOT's) $228 million 1-480 Valley View Bridge project was needed to keep traffic flowing on one of the state's busiest freeway segments. Deterioration from age and steady high- traffic volumes necessitated the replacement of the existing decks of the I-480 east- and west-bound bridges over the Cuyahoga River Valley in suburban Cleveland. To facilitate this work without creating tremendous backups and traffic delays due to long-term lane closures, the project included design and construction of a new four-lane bridge in the median gap between the existing 1-480 bridges. Now complete, the new center bridge allows for all four lanes of I-480 to be maintained in each direction while deck replacement and other repairs are made to the existing bridges, while also providing increased capacity after project completion. ODOT awarded the project to the Walsh Design-Build Team (DBT) in late 2017. This article describes how the Walsh DBT, with Jacobs Engineering as the DBT lead design firm, incor- porated an innovative approach to the design and construction of the driven pile foundations for the new I-480 center bridge. I-480 crosses approximately 200 ft (60.9 m) above the Cuyahoga River Valley. With an overall length of 4,150 ft (1,265 m) and spans ranging from 180 to 300 ft (54.8 to 91.4 m), the design and construction of the foundations for the new center bridge were critical to the success of the project. Due to their overall height and span lengths, the foundation loads for a typical pier consisted of a factored vertical load of 22,000 kips, (100 MN) plus significant overturning forces due to horizontal loads and thermal effects.

May 1, 2022

By Mitsuhiro Shibazki

I can't answer that question but I am looking at Andy, my co-author, and he says we didn't measure it. No movement. If I understand it correctly, how do we handle lateral forces in shear? The main columns were designed as pin connections so there wasn't a moment in the shear between the pile cap and the columns the steel reinforcing was used to resist that. I am not aware of how we would have installed those, it is possible to try and submerge them all if the jet grout is still fluid. They were higher than design. You are correct.

Feb 10, 2003

By A. J. Metz, Roberto Nevarez

One popular method to stabilize slopes is the use of deep foundation elements to support lateral loads from an unstable soil or rock mass. Drilled deep foundation elements are often selected due to local availability of equipment, access concerns, cost considerations and post-construction aesthetics. Often, one or more rows of deep foundation elements are installed running parallel to the slope. The elements in each row may or may not be connected through a cap beam. They work primarily in bending, and resist slope movement by transferring the earth pressures down below the potential slip surface. Design of these systems considers the effect of arching

Nov 1, 2023

By Jonathan Ernst

The Bruce Museum is an art, science and natural history museum in Green- wich, Connecticut. The museum was originally built as a private residence in 1853, and has undergone several reno- vations, the most recent dating to 1992. The current renovation is part of a $60 million capital expansion plan for the "New Bruce." The renovation includes a 43,000 sf (4,000 m2), three-story addition that will more than double the size of the museum, adding space for new ex- hibitions, education and community spaces. The proposed bottom of the foundations for the renovation sit up to 16 ft (5 m) below the Bruce Museum's existing shallow foundations.

Aug 1, 2023

By Naim Noori Samie

Lateral force rsistance of piles is analytically investigated by dividing the pile length to 3 segments. The first segment (Zone I) models the load eccentricity with respect to the soil and the pile-deck connection, using a third degree differential equation representing the shear variation along the pile. The soil is assumed to be uniform, homogeneous with an elastic-perfectly plastic behavior. The Top soil layer (Zone II) is assumed to be stressed beyond the elastic limit. A simple 4th degree differential equation represents this zone. The soil resistance is assumed to vary linearly with depth (or surcharge). The pile deformation and soil behavior determines the plastic zone length. In zone III the soil is assumed to behave elastically, hence its resistance is proportional to its deformation. A linear 4th degree differential equation is employed in this zone. The compatibility conditions are satisfied on each boundary. Maximum allowable moment and shear are investigated throughout the pile as the basic limiting criteria on lateral force capacity. In this paper the soil coefficients are taken from a proposal by ref(3), and the results are compared with the soil response as determined by the P-Y method as recommended by ref(2).

Jan 1, 1996

By Charles R. Conlon, Matthew J. Niermann

This paper presents the underpinning and excavation support systems used for construction at 2100 L Street in Washington, DC. The excavation for the proposed building extended below bedrock, which presented significant challenges for underpinning the historic Stevens School, constructed in the late 1800’s. The Stevens School was underpinned using several techniques consisting of soil mixing below an unreinforced foundation, traditional hand-dug pits to rock, micropiles below rock, and bracket piles. The excavation support system for the remainder of the project consisted of soldier piles and lagging supported laterally by tiebacks and braces. Shotcrete and rock bolts supported the exposed bedrock. This paper will discuss the design, construction and monitoring results.

By Louay Owaidat

The United States Army Corps of Engineers (USACE) Sacramento District awarded a $64 million construction contract in February 2020 to the Maloney Odin Joint Venture for 3 mi (4.8 km) of levee improvements along the Sacramento River East Levee (SREL). This project kicked off approximately $1.5 billion of work to upgrade levees along the American and Sacramento Rivers and widen the Sacramento Weir and Bypass. The project received the 2021 ASCE Region 9 Project of the Year Award. Contract 1 improved levees along five segments of the river, the longest segment being a 2 mi (3.2 km) reach from Garcia Bend Park to the Freeport Intake Facility in the Pocket neighborhood of Sacramento.

Oct 1, 2022

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 R. Chowdhury

The relevance of reliability studies for deep foundations is considered in this paper with special reference to pile foundations. Attention is drawn to uncertainties related to applied loads, the load-carrying capacity and the safety margin of a pile foundation. The essential steps in a reliability study are outlined. An essential goal of any study is the determination of the Reliability Index or Safety Index under different conditions of loading and operation. Calculations concerning probability of failure or success require an assumption to be made concerning the probability distribution of the safety margin. The significance of this and other assumptions should be clearly understood. Reliability approaches should be used to complement conventional deterministic studies.

Jan 1, 2010

By Gerry Houlahan

The east span of the 3.5 km long SF-Oakland Bay Bridge is supported by different types of foundations along its span. Starting from the west, its first 460 m section comprising twin concrete box-girders is supported by sands and rock on Yerba Buena Island. A 620 m long steel suspension span then bridges a 25 m deep channel that is formed in sediments overlying rock. Twin concrete box girder structures, each 2.4 km long, complete the stretch over the remainder of San Francisco Bay to the engineered earth fill landing at its east end. For most of its length, the Skyway bridges water 3 to 10 m deep over soft surficial Young Bay Mud. The foundation types include spread footings with hold-downs, steel and concrete piles that are set in drilled rock sockets up to 3 m in diameter and 2.5 m diameter steel tubular piles driven to penetrations of up to 100 m. The design and construction-related considerations are presented. The different foundation types, influences of the site geology and earthquake demands on the substructures are discussed. The seismic motions of the bridge superstructures and substructures, as well as the depth-varying soil motions, influenced the foundation design. Together with performance-based design criteria, including post-earthquake footing displacement limits, these seismic demands influenced various aspects of the foundation design, including the use of battered and vertical piles.

Jan 1, 2013

By Greg Halsted, Joshua Gilman

Today's civil and geotechnical engineers play an important role in helping to achieve sustainable infrastructure. To address environmental sustainability and climate change caused by green- house gas (GHG) emissions, all engi- neers must adjust their traditional approach to materials, design and construction practices to include a focus on minimizing carbon dioxide emissions. The considerable influence that geotechnical engineers have on projects provides an important oppor- tunity to affect positive change. The carbon footprint of the construction methods and materials used for foun- dations can be as much as 8-9% of a new building's total carbon footprint, and geotechnical engineers have an op- portunity to evaluate alternatives based not only on cost, but also the long-term environmental impacts. Growing environmental considerations and societal concerns are influencing the selection of construction materials and methods, including cement and concrete's role and significance for infrastructure applications today and in the future.

Jan 1, 2023