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By Maral Papazian Bedian

Construction contracts in the USA contain the clause "Value Engineering" ? an interesting and curious clause allowing contractor initiated design changes. Misleading is the interpretation of value engineering implying cost saving and sharing with the owner, and curious is the timing, just before beginning of actual construction. It is not surprising that such a clause would simply be ignored, because it involves change, often major design changes in very short time; and change is feared, moreover, it is vehemently resisted by all parties, owner, designer, contractor. The problem in the USA may lie in the divergence and separation of the two entities: Designer/Engineer and Builder/Contractor, assigned to the "one" engineering project. The priorities and incentives of these two groups are very different. The Engineer spends years, even decades, in design and prepares contract drawings often without a deep understanding of construction methods. Worse, with all the time available to him and in our era of tremendous advances in computational methods and speed, the designer turns in plans that are inexcusably exaggerated code-based design with excessive safety factors. As to the Contractor, he builds, often without appreciation of design principles or regard for design engineers. Redesign to apply a new technology or optimization of an inferior design just before construction becomes unthinkable. It is not surprising that adverse and hostile relationship between the designer and the contractor is a norm with extended disputes and claims, not to mention the cost these entail. Surprisingly, "Value Engineering" was successfully implemented in record speed on several very large projects in the metropolitan New York area. The process of change was unconventional, painful, and even comical. Four case studies are presented: two Design/Build: the 1.2 billion dollars Hudson-Bergen Light Rail Transit System in New Jersey and the 90 million dollars MTA Bus Depot in Manhattan, and two Conventional Design/Bid/Build: the 90 million dollars Queens Boulevard Bridge and the 150 million dollars Long Island Expressway.

Jan 1, 2002

1.1 The parties agree to submit all claims, disputes or controversies arising out of, or in relation to, the interpretation, application or enforcement of this agreement, including dispute resolution procedures, to sequential mandatory discussion, mediation and arbitration for resolution of all disputes before, and as a condition precedent, to self-help, arbitration, judicial action or other remedies. This mandatory procedure will resolve each dispute within one-hundred (100) calendar days. Any deadline falling on a federal holiday or weekend will be the next working day. Breach of this disputes process shall constitute a material breach of contract for which the aggrieved party may recover all costs, including attorneys fees, interest and other expenses necessary to resolve the dispute through litigation. The obligation to discuss and then mediate and arbitrate covers all disputes arising from every aspect of the Project to be built by the owner, including, but not limited to, design, engineering, bonding, indemnification, labor, material and services, and the acts or omissions of any related party for whom a party to this agreement may stand responsible.

Jan 1, 1994

By Shane Baker

Cementation Foundations Skanska Ltd encountered many significant challenges in designing and constructing the foundations for the LNG (Liquefied Natural Gas) tanks and associated structures at the Isle of Grain, Kent, UK. With LNG cargo ship levels fixed by the adjacent English Channel, the platform could not exceed critical thickness in order to achieve final grade level, so a safe and efficient working platform for construction equipment on extremely poor alluvial soils was designed and installed. The detailed pile design also required particular analysis of the pile group behaviour and considered seismic load cases not usually associated with UK pile design. Continuous flight auger (CFA) piles were the chosen foundation solution and design was verified through preliminary and working pile tests both axially and horizontally. Contaminated land and existing foundations from a previous oil terminal meant that removal of spoil was extremely costly so specific measures were taken to minimise the off-site disposal. The management of a package of general Civil Engineering in addition to the piling scope, coupled with an unrelenting production program has forced a raising of the bar for this foundation technique.

Jan 1, 2006

By Bengt H. Fellenius

Session 2, Deep Foundation without Soil Excavation, has attracted no fewer than 22 papers dealing with subjects from soil improvement by grouting, injection, and deep mixing techniques through vibroflotation and special piles, including aspects pertaining to conventional driven and bored piles. In the short time available, it is not possible to both do justice to the papers and provide a critical review of the state-of-the-art. Instead, to meet the objective of making the next half hour worthwhile to the audience, I have chosen to comment on a few special points brought forward in the papers and thereafter to discuss more in detail a couple of aspects I have deemed to be of general interest. Four papers deal with jet-grouting, injection, and deep mixing techniques: DOMSKI, J. J. Reinforcement of subsoil under the foundations of historical buildings in Cracow using deep injection technique. RESTELLI, A. B, BERTERO, M., and LODIGIANI, E. Deep mixing technology to improve the bearing capacity of a very soft clayey soil under an earth embankment.

Jan 1, 1994

By Frank Callanan

The Ameristar Casino expansion project included the design and construction of a 25-story hotel and 9-story parking structure expansion. The site is located in a floodplain on the banks of the Missouri River in Saint Charles, Missouri, where the underlying soils are potentially liquefiable. The geotechnical engineer performed subsurface exploration and analysis, which included site-specific seismic response and liquefaction, and provided geotechnical design recommendations. In the event of an earthquake, post-liquefaction settlement was calculated to be approximately 14 inches. Additional project constraints included wetlands protection, construction adjacent to the existing facility, flood protection and river bank stability. Because of the liquefaction issue, the geotechnical engineer consulted with a specialty geotechnical contractor on ground improvement methods. This consultation led to a proposal to eliminate deep foundations from the design and support the structures on shallow and mat foundations. The geotechnical engineer assisted the design team with foundation design analysis and value engineering assessments. Together with the project team, the geotechnical engineer used the data to evaluate foundation options and construction methods to overcome the site challenges and concluded that ground improvement was the optimum course of action. Because of the nature of the site constraints, a number of ground improvement methods were needed. The geotechnical engineer evaluated the methods proposed by the geotechnical contractor and provided the technical specifications for the ground improvement bid package, which included vibro-compaction, compaction grouting and micropiles. The ground improvement allowed for the use of shallow foundations (mat and spread footings), which provided the client with significant time and cost savings over the deep foundation alternatives.

Jan 1, 2009

By Maurizio Siepi, Stefano Trevisani, Pagliaccim Federico, Daniele Vanni

"Abstract: The paper describes a large innovative project completed in 2012-20123 by Trevi Group, to develop equipment capable to install ultra-deep diaphragm wall. The project highlights the capacity of SOILMEC to design and build a new hydromill able to reach an unprecedented depth of 250 m, including new devices for monitoring and correct the verticality. The entire project can take advantage of the long and solid experience matured by Trevi and Rodio (now part of Trevi Group), developing in house or, else, select the elements necessary for a high quality product in the ground.The paper describes the results of different systems used to monitor and control the verticality and the twist of panel during excavation, together with the method used to pour concrete. Finally, the results of verification coring and lab tests on concrete samples recovered at various depths are discussed. The test field has been supervised by representatives of three of the major Italian Universities, and lasts almost one year from August 2012 to June 2013.The verification holes made use of an innovative combination of directional drilling and coring, to check the quality of the plastic concrete for the full length of the panel. The data confirmed that the test panel has high quality concrete, meeting or exceeding to the prefixed requirements.With this test, super-deep cut-off walls reaching depths of 250 m have become a reality. This would change the perspectives of dam engineering both for existing dams rehabilitation and for new dams design and construction. With the execution of this test panel, the technology of milled concrete cutoffs has made a ”quantum leap”, pushing the limit of practicable dams."

Jan 1, 2014

By W. F. Van Impe

The design of piles and of pile groups has remarkably progressed over the past two decades. The in­creasing complexity of the building concept implements a more rational approach of the deep foundation capacity and its interaction with the structure. Moreover, the understanding of the soil characteristics relevant to deep foundation behaviour, is continuously in progress because soil parameters are always more accurately determined; which also contributed a lot to the recent developments in pile capacity design. At last, due to the increasing sensitivity of buildings to deformations, continuous attention must be also paid to pile group settlements. The aim of this report is to discuss some of the mentioned more important pile design developments.

Jan 1, 1994

By Aly M. Mohammad

The Delaware River Tramway will link civic and retail developments in Philadelphia, Pennsylvania and Camden, New Jersey. Twin 300-foot towers will anchor the cables at either side of the river. Four high capacity drilled shafts designed by the Geotechnical Department of DMJM+HARRIS support each of the towers. At the Philadelphia tower, each 6-foot diameter shaft extends 130 feet deep and terminates with a 30-foot rock socket. The shafts are situated within the footprint of an existing relieving platform, which complicates the typical construction sequence. Also, the subsurface conditions at the site provide a unique challenge in both the design and construction of the drilled shafts. During the construction of the four-drilled shafts for the Philadelphia tower, a 6000-ton Osterberg load test was performed on the first shaft to verify design assumption and confirm the shaft capacity. The results of the test were utilized to establish load transfer characteristics and develop foundation design parameters suitable for the site conditions. By doing so the Design Engineer was able to reduce the length of the rock sockets on the remaining production shafts by approximately 5 feet per shaft. As a result, the test provided a significant cost saving to the Owner by eliminating 15 feet of rock drilling from the construction costs. This paper presents a description of the unique design and construction methods adopted for the foundations, also on the Osterberg load test including equipment used, number and locations of strain gages, and interpretation of results. The results and findings presented in this paper could benefit both the design and construction industries because it provides a comparison between geotechnical design assumption and actual field measurements; which has always been a challenge particularly for rock formation.

Jan 1, 2002

By Gordon] [Reavis

Halliburton Services and Brown & Root have developed a unique foundation system that blends oilfield and construction technologies to construct deep foundations which offer significant advantages across a variety of soil profiles. This highly efficient system is being developed to meet the construction industry's needs into the 21st Century. Based on a concept initially introduced to Halliburton Services by V.L. Schellhorn in 1987, Halliburton combined their existing cement slurry mixing and pumping technology with oilfield drilling practices and a new tool design to field test the viability of the concept. Results looked encouraging, and Halliburton asked it's sister company, Brown & Root to evaluate and further develop the process. With Brown & Root's knowledge of the construction industry, the original concept has developed into a viable and efficient foundation construction system.

Jan 1, 1993

By Maurizio Siepi, Fabio Santillan, Lyndon Bedford, Carlo Crippa

"Abstract: Wolf Creek dam, on the Cumberland River in Kentucky, US, operated and maintained by the Nashville District of the USACE, is the Corps' largest reservoir east of the Mississippi river. The 1748 m (5,736 ft) long Wolf Creek dam combines earthfill and concrete gravity sections. Construction began in 1941 and was completed in 1950. The dam showed signs of instability in the 1960’s, and in the late 70’s an in-depth project of rehabilitation was undertaken, using both grouting and secant piles. The works saved the dam, but in the late 90’s further signs of distress worried the Nashville district of USACE which, after a study conducted on the water seepage, concluded that construction of a new concrete barrier cut-off wall was needed. In 2009, the $341.4 USD million contract was awarded to TREVIICOS-SOLETANCHE JV.The new wall, located upstream of the concrete monoliths, has a minimum thickness of 60 cm (24 in.), and runs the length of the embankment, into the right abutment, for about 4,200 feet. The founding depth reaches 84 m (275 feet), well below the zone of solutioning. With a total surface approaching 92,903 sq.m (1,000,000 sq.ft), the Wolf Creek barrier wall is unlike any other project in the world.The construction of the cut-off wall followed a complicated but logical sequence of several operations, involving a variety of technologies: grouting, hydromill, directional drilling, and secant piles with reverse circulation. The intensive rock grouting program was aimed to minimize the risk of slurry loss and extend the positive cut-off further deep. Subsequently, an Encasement Concrete wall was installed with hydromill, toeing into the rock, to protect the embankment during the following phases. Smart holes were then drilled into the Encasement wall down to the final depth. Eventually, the holes were used to install the secant piles by employing the reverse circulation piling method.An extensive verification campaign has confirmed the superior quality of the cutoff wall consisting of 1200 secant piles, exceeding by far USACE’s requirements. The main project was substantially completed in early 2013. A small portion of secant piles wall will be installed downstream of the dam, to close the switchyard, finishing the project in the early months of 2014.IntroductionWolf Creek Dam is located on the Cumberland River in south-central Kentucky. The Nashville District of USACE operates this multipurpose dam to provide hydropower, flood control, water supply, and water quality benefits for the Cumberland River system and surrounding region. Lake Cumberland, created by the dam, impounds 7,400 million cu.m (6 million acre foot) at its maximum pool elevation of 232 m (760 ft) above sea level. This lake is the largest reservoir east of the Mississippi and the ninth largest in the United States, and attracts 4.89 million visitors, more than Yellowstone National Park (2.87 million).This paper describes the recently completed works for the rehabilitation of the dam, accomplished by TreviICOS-Soletanche JV with the construction of a new Barrier Wall."

Jan 1, 2014

By SungJe Chi

Intrinsic remediation is the effect of natural attenuation mechanisms - dilution, dispersion, sorption/precipitation and biodegradation - reducing contaminant concentrations in ground water to specified levels at predetermined compliance points in the aquifer. Current monitoring and modeling for post closure was used to assess the current and long-term potential of intrinsic remediation of contaminated seepage originating from a large reactive (sulfidic) tailings impoundment near Questa, New Mexico. It is concluded that the natural attenuation mechanisms of precipitation within the tailings (as a result of buffering) and dilution/dispersion within the aquifer are currently active and likely sufficient to reduce contaminant concentrations to below state standards in the long-term. Other natural attenuation mechanisms such as sorption and biodegradation within the receiving aquife4s) were not assessed here, but are likely further reducing contaminant concentrations. Active interception and recovery of the seepage water is being maintained until monitoring demonstrates that intrinsic remediation has successfully achieved the level of water quality control required.

Jan 1, 2017

By S. T. Kok

This paper presents a case study in West Malaysia for passive piles failure in very soft marine clay in open excavation. In this particular case, the thickness of the very soft marine clay ranges from 5 m to 7 m (16 ft to 23 ft) from the ground surface. Preliminary site investigation reported SPT ?N? value of zero for the very soft marine clay. The design was based on a deep foundation utilizing driven piles to support the superstructure. During pile cap construction, the piles were subjected to uncontrolled open excavation, inducing bending moment in the piles, resulting in some cracked and broken piles. Analyses were carried out using an existing three-dimensional finite element code with a non-linear soil model to predict the response of these piles during excavation. Finally, the predictions of pile responses during excavation were compared satisfactorily with the observed results.

Jan 1, 2009

By Stefan Larsson, Sebastian Adevik, Sadek Baker, Razvan Ignat

"Abstract Uncertain strength, deformation and flow properties in dry deep mixing columns often lead to conservative choices concerning design values where the design is regularly complemented with a surcharge fill. The surcharge not only leads to increased cost but also to logistical problems where the surcharge is a physical obstacle. The deformation properties of a ground improvement were studied by means of two small embankment load tests. The settlement measurements were also used in FEM analyses, where the effect of surcharge on creep settlements was investigated. Based on the results, the effects of the surcharge were considered negligible and could safely be ignored. The project is an example how the contractor can use a field test as an effective design approach.IntroductionGround improvement of soft soils with dry deep mixing columns, or lime-cement columns, is often combined with a surcharge fill. The main reason for using a surcharge is to force the primary settlement and some of the secondary settlement that would have occurred under the final embankment height alone, to take place under the surcharge loading. Another reason is to level out uneven settlements. Strength and deformation properties in improved soil cannot be sufficiently assessed in advance, before columns have been tested on-site, and this uncertainty often lead to conservative choices concerning design values. In order to compensate for a slow forecasted consolidation process, the design is regularly complemented with a surcharge. The surcharge not only leads to increased cost but also to logistical problems where the surcharge is a physical obstacle.Extensive research undertaken by Åhnberg (2006, 2007) shows, by means of triaxial and oedometer tests, that cementation processes and a load acting on the columns during hardening, makes the improved soil to behave as a heavily over-consolidated soil due to an increase in quasi pre-consolidation pressure. The effects of using a surcharge on the time for consolidation and creep properties are thus probably small, since the stress level does not normally exceed this quasi pre-consolidation pressure. A study presented by Venda Oliveira et al. (2013) shows that the stress level within small ranges has limited effect on the creep properties.This paper presents a case study where the deformation properties of a ground improvement using dry deep mixing columns was investigated by load tests on two small test embankments. The tests were performed at the Interchange Värtan project site, which is part of the Norra länken infrastructure project in Stockholm. The tests were not performed as a research project but simple load tests performed by the contractor with the purpose of rationalizing the design delivered by the client. One purpose of the load tests was to assess the deformations when the columns are loaded temporarily by overlaying concrete works. Another purpose was to provide some input data to a study of the effects of using surcharge on creep settlements. The analysis was conducted as finite element modeling using the commercial code PLAXIS, where creep settlements can be simulated using the built-in Soft Soil Creep model."

Jan 1, 2014

By W. Tom Witherspoon

Many Engineers are skeptical and cautious about skin friction factors for the portion of drilled piers where temporary casing is used. This has led Texas engineers in many cases to eliminate skin friction values for the cased section, which necessitates deepening the drilled shaft to compensate for the loss in the cased section. This paper has provided field test data that supports inclusion of skin friction in the temporarily cased hole section as a contributing factor in total axial capacity as comparable to open hole shafts of the same diameter. Reasons for the resultant friction values are provided including; remolding of the cased clay section and the increased pier circumference necessitated by the oversized casing required for adherence to the engineers shaft diameter specification.

Jan 1, 2009

By N. Som

The pile capacity in cohesive and granular soils depends on a number of parameters. The values of these parameters as recommended by Indian Standard Code of Practice vary over wide ranges. A designer often finds it difficult to select appropriate values of these parameters for realistic estimate of a pile capacity. The present paper makes a critical review of the values of the parameters given in Indian Standard Code of Practice and suggests a realistic approach to selecting them in the light of recent research.

Jan 1, 1996

By Robert Fernie

Demographics and Infrastructure demands have led to a significant increase in construction of: deep basements for buildings and, trough structures for Highway and Rail/Metro. Concrete embedded walls used for temporary works can be incorporated into permanent works and because of this (and geological conditions) tend to be favoured in UK. This paper considers British practice in the provision of diaphragm (slurry) walls secant (true and pseudo) piled walls contiguous piled walls Plant utilisation, construction techniques, reinforcement placement, connections, propping, water tightness, tolerances, general UK practices and their relation to design practices are discussed. [ ]

Jan 1, 2000

By Nikolaus Schneider

"Abstract: The combination of failure in joints of diaphragm walls and their exposure to water pressure may have far reaching effects ranging from water leakage to the risk of catastrophic loss of stability for the retaining wall and civil structures behind it. Investigations of imperfect joints in diaphragm walls have led to the development and testing of a quality tool to monitor the joint integrity of diaphragm walls during construction. By applying independent mechanical sensors (“joint inspector”) to the steel frame of hydraulic or mechanical grabs, it is now possible to record the surface conditions of exposed primary joints during the construction of secondary panels. This allows for the implementation of corrective action during the construction process should joint quality not indicate a watertight connection to the adjacent panel. The joint inspector, used for different types of stop ends, was tested on a full scale test field at several construction sites. The implementation of this new quality tool drives a new quality standard for deep excavations in inner city areas.General introduction to diaphragm wallsDiaphragm walls are reinforced concrete elements constructed using bentonite slurry to temporarily support an open trench in the ground. They are used in two main fields of application in civil construction, as foundation elements for vertical and horizontal loads (barrettes) and as retaining walls for excavation pits.Particularly for deep excavation pits in inner city areas, diaphragm walls are used as temporary or permanent walls of retaining walls. Alternative retaining wall systems would be secant pile walls, sheet piles or soldier piles, but these have disadvantages in structural strength when compared to diaphragm walls. If the vertical load of existing buildings next to the excavation pit has to be accommodated, the most practical solution can be found using diaphragm walls supported by prestressed anchors, steel struts or slabs."

Jan 1, 2014

By Enrique Ibarra, Manuel J. Mendoza

"Abstract: This paper describes the current state-of-practice for the design of cast-in-place drilled shafts in granular soils under axial loading, addressing recent advances that take into account the surrounding soil grain size distribution and their behavior. The important role of the gravel content in the shaft response under axial loading is emphasized. Usual design approaches in Mexico are described, and the results of load tests from different sources are discussed. The analysis emphasizes the primary contribution of the lateral area of shafts to their axial bearing capacity, raising doubts regarding the common local idea of “point bearing shafts”. Finally, some lines of research are noted to permit advances in the important field of deep foundations. 1 INTRODUCTIONIn Mexico, cast-in-place drilled shaft foundations are widely used to support various structures in the west area of Mexico City, where alluvial and volcanic deposits predominate. Deep foundations are also used in modern construction works located in other major cities of Mexico. In fact, the use of drilled shafts for tall buildings and overpasses in the center of Guadalajara as well as in transportation works related to the Metro and roadways in Monterrey is well known. It is worth mentioning that these same structures have been applied in road bridges throughout the country.Procedures for pile construction in Mexico have been basically the same for the past 20 years (Paniagua et al., 2005); however, modern equipment has been incorporated into the construction industry, including innovations in sludge-drilling technology, control and the quality of the castings. In addition, novel and efficient procedures such as construction with continuous auger displacement piles have been implemented (Auger Cast in Place, ACP) and have begun to be used locally with success (Schmitter and Paulin, 2006).However, it can be argued that the technological developments that have resulted in more efficient construction procedures have not included a breakthrough in the full understanding of the phenomena or basic mechanisms of load transfer from piles to the surrounding subsoil and therefore in supported, tested and practical design methods. This is particularly true when seeking to determine the unit side shear strength of shafts drilled in granular media with gravels, where it has been observed that the commonly used calculations developed for sands underestimate the load-bearing capacity by frictionin a most important way. Due to the above reasons, it seemed appropriate to present in this paper a review of the current stateof- practice in Mexico for the design of cast-in-place drilled shafts, particularly in granular media, highlighting some recent advances and research that takes into account the grain size distribution and behavior of granular soil."

Jan 1, 2014

By David V. Lewin

Heavy structures in central Cleveland, Ohio, are supported on raft foundations, driven piles, or caissons. Settlements can be predicted and structures are designed to accommodate such settlements. On one project the settlements were not provided for in the design of the structure. Soils are sands, silts, and varved clays to shale. A rift in a central area is 600 feet deep. Solutions to problems, and results, are detailed.

Jan 1, 1985

By D. Kolymbas

A simple formula is introduced which allows the evaluation of dynamic pile tests. The following case is considered: The pile top is dynamically loaded by an impact. The velocity v of the pile top is recorded over the time. Let v1 and v2 be the first and the second maximum of this curve. Then, the pile bearing capacity (resulting from ideally plastic resistance at the pile wall and at the tip) can be set approximately equal to Z(v1- ½ v2), where Z is the impedance of the pile cross section. Due to the assumption of ideal plastic resistances, radiation damping needs not be taken into account. Material damping may be important in rate sensitive soils (such as clay, even if it is highly overconsolidated). A simple correction procedure for material damping is proposed.

Jan 1, 1989