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By Lu Peiyan

A computation model of soil-pile (wall) interaction under lateral loading is presented in this paper. The model has been applied to some engineering projects, and the comparison between computation result and measured result shows good agreement, so the model is proved to be correct and practical.

Jan 1, 1991

By I. Stanculescu

The consolidation of thick and very compressible soil deposits by stone columns associated with cast-in-place plain concrete columns, has been performed for shallow foundations of some heavy industrial structures. The reduction of settlements and increase of soil bearing capacity were thus ensured as a result of soft soil interaction with stone and concrete columns. The results of model tests and in situ large scale applications are presented. A calculation procedure is also suggested for foundation bases improved by the proposed method.

Jan 1, 2010

By P. Ventura

Reliability of the liquefaction analysis is based on data plotted as by piezocone, as by deep vibrocompactation monitored tests. The negative porewater pressure, re lated to hydrostatic value, recorded by piezocone, is a good marker of the absen ce of the liquefaction. Systematic measures of the ground settlements, inside the vibroinfixed steel pipe, allow to locate the liquefable strata with loose density. Experimental study of the combined soil improvement by stone columns is carry out in particular in sea bed. The interaxis of the columns for the best efficiency is valued as of the vibrocompactation, as of the drainage effects, especially during earthquake.

Jan 1, 1989

By Mathew Avery, Colby Barrett

In November 2016, a 7.8-magnitude earthquake caused more than 100,000 cubic meters of rock and debris to tumble down and bury the transportation infrastructure below Ohau Point in New Zealand. All routes between the northern and southern portions of South Island were severed. To undertake the rebuilding efforts, the New Zealand government established North Canterbury Transport Infrastructure Recovery (NCTIR) – an alliance to repair the road and rail networks between Picton and Christchurch. NCTIR’s aim was to have the road open by Christmas 2017, but work also continued into 2018 to complete a number of safety improvements along the highway. The presentation will review the initial remediation attempts, the necessity to re-evaluate the original efforts, the need to incorporate techniques that were “outside-the-box” and different from traditional methods, and the logistics and planning that were required to complete the work safely. INTRODUCTION Shortly after midnight on Monday 14th November, a magnitude 7.8 earthquake struck the small South Island settlement of Waiau in North Canterbury, 100km north of Christchurch. The quake was the largest in New Zealand since the magnitude 7.8 Dusky Sound earthquake in 2009 (GNS 2016). While shaking was widespread with over 15,000 recorded ‘felt reports,’ the worst shaking occurred about 50 seconds after the quake rupturing started. The energy of the tremor progressed north over several minutes with surface rupture recorded on a total of 21 faults. The length of all the fault ruptures combined was close to 100km (GNS 2016). The degree of ground shaking was high, recorded as Modified Mercalli Intensity Scale (MMI) Level 8 – Severe. This level of shaking causes considerable damage in ordinary buildings with partial collapse including fall of chimneys, factory stacks, columns, monuments, walls, etc. At a human level, people experience difficulty standing; while furniture and appliances shift. Geologically, the damage depends on the geological setting. In Kaikoura and the surrounding area, especially the coastal highway State Highway 1, north and south of the town, many of the slopes consist of over steepened weathered, fractured greywacke. During the quake, the shaking caused significant and widespread damage with a total of 26 major slips (and many smaller slips); closing both State Highway 1 and the Main North Rail Line between Picton and Christchurch.

Jan 1, 2018

By William Van Impe

A most renewing and promissing soil displacement screw pile is called the O-pile. The O-screw pile is a soil displacement auger pile based on a screwing in - screwing out procedure. The displacement auger head consists of a discontinuously diameter - increasing steel tip, on top of which the continuous screw flange with variable pitch is mounted. The soil displacement is kinematically ensured by downwardly oriented slots mounted on the auger head at different well chosen locations on the flanges. This leads to a very efficient lower energy screwing-in sequence of the pile and consequently to a high penetration rate. A test loading program of instrumented O-piles has been carried out in order to evaluate the load settlement behaviour, the shaft and tip capacity of the O-pile, including its specific installation parameters.

Jan 1, 1996

By Paul J. Axtell

The results of in-situ geophysical cross-hole tests on improved soil by soil mixing (SM) and jet grouting (JG) are described. This testing was conducted on soil improved by SM and JG columns constructed in the downstream free-field of Tuttle Creek Dam near Manhattan, Kansas as part of the seismic retrofit. Results of similar geophysical testing performed on untreated soil in the vicinity of the Downstream Test Program (DTP) area, as well as beneath the embankment at several locations, are also described and used for comparison purposes. In-situ shear moduli are also compared with those determined in laboratory resonant column tests. The increase in stress wave velocities and associated shear moduli by SM and JG treatment are presented for use in liquefaction potential and seismic deformation analyses of SM or JG treated soil. This data is required to determine the decrease in liquefaction potential and earthquake-induced permanent deformations due to SM or JG with respect to that of untreated soil.

Jan 1, 2008

By Scott A. Walker, Frank L. Rollo

"The San Francisco Museum of Modern Art (SFMOMA) in downtown metropolitan San Francisco, California, is supported on a mat foundation. Although the mat foundation of the original museum was designed to accommodate a future expansion, the plans for expansion that developed in 2010 required a larger footprint to accommodate the new space requirements of the museum. The new, larger expansion was designed by lead architect Snohetta. It will be a tall 12-story, steel-framed building occupying an area that was once the eastern part of the existing museum as well as two adjacent and newly acquired parcels.As designed, the expansion includes a 30-foot-deep excavation which is surrounded by adjacent buildings and improvements. Because of variable subsurface conditions at the site, geotechnical challenges included mitigating anticipated differential settlement between the existing and new foundations, preventing overstressing of the existing mat foundation, controlling groundwater to prevent settlement of surrounding improvements, and providing temporary support of adjacent structures during excavation for the new basement.To address several of the geotechnical challenges, soil-cement mixed (SMX) ground improvement was recommended by Treadwell & Rollo. However, during contract negotiations and construction, the specialty contractor proposed using jet grouting as an alternative technique for ground improvement. The jet grouting approach was accepted in principal, but when implemented was only marginally successful. Accordingly, the contractor eventually installed SMX panels using a Cutter Soil Mixing (CSM) machine. Because the CSM machine was a late arrival during construction, the contractor was not able to take advantage of the ground-improvement technique to install many of the shoring elements that we had originally recommended (such as the cut-off shoring wall). In the end, SMX panels were installed as ground-improvement beneath the new mat foundation to (1) reduce the potential for liquefaction in clean sand below the groundwater by providing increased rigidity to the soil, (2) reduce the potential for disturbing a weak underlying marsh deposit during construction, and (3) transfer vertical building loads to a layer of underlying dense sand.This paper also discusses the quality control and quality assurance programs that were implemented to check that the ground-improvement techniques used were thorough and complete and provided the required strength to transfer the new foundation loads to the underlying strata."

Jan 1, 2014

By Peter Middendorp

Pile foundations are widely applied in the Netherlands because of the soft soil conditions. One of the popular pile types are cast-in-situ piles, which have to be integrity tested to get accepted. Integrity testing has been applied for more than 30 years, with the number of integrity test performed nowadays exceeding 400,000 per year and subsequently there is a substantial amount of practical experience with this testing method. This paper will deal with some basics of integrity testing and describe some of the techniques that have been adopted in the Dutch pile testing practice, like detection of pile head defects with a spike type hammer pulse, and the site average or pile group average for the qualitative interpretation of measured signals.

Jan 1, 2006

By Douglas W. Christie

Deep foundations in Washington, DC have played a role in the city?s development since the 19th century. Designers of government and commercial buildings sought deep foundations initially to minimize settlement of structures. As the western portion of the National Mall was made by filling in portions of the Potomac River, numerous memorials and monuments on the Mall required deep foundations. In recent years deep foundations have been used to allow underground construction for various reasons. Commercial developers have sought to maximize the use of sites by developing below-grade space for parking to meet code requirements and offset the limits on building heights. Underground museum and gallery space has been constructed to expand public space while preserving open space above grade. Access and security concerns have prompted the design of underground visitor centers rather than above-grade structures.

Jan 1, 2006

By Rick Deschamps

The Block 76 project includes the demolition and redevelopment of an entire city block for mixed use retail, office and residential properties directly adjacent to Historic Temple Square in Salt Lake City, Utah. Excavation was carried out 65 ft below street grade and by as much as 50 ft directly below adjacent buildings supported by shallow foundations. Movements of the earth retention system and adjacent buildings were monitored in real time using automated equipment which complemented traditional geotechnical instrumentation. In the areas immediately adjacent to the existing buildings 9 stories or greater, anchored diaphragm walls were employed. Areas of the site not supported by diaphragm walls employed a soil nail wall system. Jet grouting was used for water cutoff in lieu of dewatering along the north and east sides of project. In total, the earth retention scope included 45,000 sq. ft of diaphragm wall, 104,000 sq. ft of soil nail wall, and micropile underpinning of 3 buildings. This paper provides an overall description of the Block 76 project. A detailed account is provided of the technical and commercial lessons learned. The project provided a unique example of how an owner can receive best overall value by acceptance of some technical risk up front. Benefit was gained by allowing the contractor to reduce contingencies within the bid from unknowns on a fast-track project.

Jan 1, 2009

By Thoedtida Thipparat

The diaphragm walls and barrettes are very important to the constructions of multi-storeyed buildings, elevated expressways, subway railway stations, etc. Uncertainties particularly increase in accordance with the construction progress. Overcoming uncertainties influences the construction goals including achievement of time. This paper is aimed at proposing an uncertainty assessment and delay evaluation model to assess uncertainties and evaluate delay resulting from those uncertainties. Neurofuzzy systems (NFSs) for assessing uncertainties and evaluating delays are developed. Artificial neural networks (ANNs) have ability for learning from the past data and generalizing outputs for the next applications which are provided for fuzzy logic systems (FLSs). FLSs have ability for exploiting the tolerance of imprecision and uncertainty. FLSs provide the reasoning to the ANNs. Uncertainties affecting each operation were assessed and delays were evaluated by following steps of the proposed model. The uncertainty assessment and delay evaluation approach was applied to a diaphragm wall and barrette construction to demonstrate how to implement the proposed model. The results of the test case application were used for handling delay at all operations regarding the corresponding uncertainties.

Jan 1, 2006

By A. B. Desai

The construction of 1144 nos. of piles, each 1.5 m diameter, bored-cast-in-situ type and varying in depths from 6.5 to 23m, has been completed as foundation for 26 piers of 548 m long aqueduct across Orsang river to carry 1128 m3 water of Narmada Main Canal of the Sardar Sarovar Project in Gujarat. These piles are socketed 1.5 m into foundation grade rockmass. The portal system of 44 nos. of piles and pile cap at the top for each pier is analyzed considering the portal fixed at bottom of piles. The borings for pile shaft were done deploying reverse mud circulation rigs and also by conventional chiseling and bailing operations. Besides vertical loading tests and lateral loading test on piles, dynamic tests such as low strain integrity testing on 290 piles and high strain pile testing on 17 piles were also conducted. The results indicated that (a) the settlement/ displacement are much less than the prescribed limits (b) good quality of concrete (c) piles are firmly socketed and (d) piles have adequate structural capacity to withstand the design load.

Jan 1, 1996

By Daniel L. Hanson

This paper presents a case history of the design, installation and performance of a tied-back tangent caisson retaining wall which was constructed as part of the Third Harbor Tunnel project currently underway in Boston, Massachusetts. The Third Harbor Tunnel project consists of a large multi-lane transportation tunnel which is being constructed by the sunken tube method. In this type of construction, the tunnel alignment, slopes and bedding are excavated and installed underwater and the tunnel sections floated over the proper alignment and sunk in place. The tangent caisson retaining wall discussed in this paper was constructed to provide support of the upper portions of the tunnel excavation at the East Boston Portal where the tunnel exited from below the harbor and continued underground on shore. A portion of the tangent caisson retaining wall was also utilized to provide earth support for the barge unloading facility where spoil from the tunnel excavation was transferred to surface vehicles for removal from the site. PROJECT BACKGROUND The tangent caisson retaining wall was constructed by The Millgard Corporation (TMC) as a subcontractor to the Boston Third Harbor Tunnel Contractors, a Joint Venture which consisted of the firms of Morrison-Knudsen Corporation, Interbeton Inc., and J.F. White Contracting Company. The entire project team is listed below on Table 1. The design of the tangent caisson wall system was performed by Hanson Engineering, P.C. (HE) acting as design consultant to TMC. The retaining wall system incorporated a single row of pressure injected earth anchors (tie-backs) as part of the design. The earth anchors were designed and installed by Drill Tech as a subcontractor to TMC.

Jan 1, 1994

By Flor De Cock

The paper reflects part of the work from the European Regional Technical Committee on Piles (ERTC3) during its mandate between 1994 and 1999, and, in particular, describes the find­ings from an International Seminar held in 1997 in Brussels on European practice for design­ing axially loaded piles. The seminar included contributions from 17 European countries, each of which provided a synopsis of their respective national design approaches. This paper pays particular attention to the design methods based on laboratory and in-situ test data for both bored and displacement piles.

Jan 1, 2002

By Fabrice Mathieu

The Cutter Soil Mixing (CSM) provides a cost effective solution for the rapid construction of retaining and cut-off walls using new equipment developed from diaphragm wall cutter technology. CSM consists of cutting and mixing drums mounted on compact hydraulic motors. Soletanche Bachy CSM has been designed to leave the space above the tool free, thereby mixing the soil efficiently during all the phases of the wall construction, with high penetration rates. The precise positioning and verticality of the wall is achieved using a kelly bar and full monitoring. Soletanche Bachy CSM is a versatile equipment which can be mounted on various carriers: pile rigs, hydraulic crane, carrier equipped with telescopic mast. The major phases of Soletanche Bachy CSM development are presented, including the results of an extensive trial carried out in Le Havre (France). The soil consists of hydraulic fill with soft soil lenses overlying sandy deposits. 20m deep panels were constructed to support a rectangular shaft. During the construction, and after its completion, the shaft was subjected to an extensive series of tests followed by a partial excavation. The paper discusses also the future development of the technique and its potential applications.

Jan 1, 2006

By Mark R. Svinkin

Construction-induced vibrations may be detrimental to adjacent structures and sensitive electronics operating nearby. Construction vibration sources have a wide range of energy and velocity, as a function of time, transmitted on the ground. Analysis of existing methods for predicting ground and structure vibrations shows that empirical equations provide calculations only of amplitudes of vertical soil vibrations with insufficient accuracy. This paper presents the application of the impulse response function concept to solve the geotechnical problem of predicting ground and structure vibrations before installation of vibration sources. Impulse response functions reflect real behavior of soil and structures without the investigation of soil and structure properties. A procedure is presented to compute predicted ground and structure vibrations. Good agreement is found between predicted and measured records.

Jan 1, 1999

By Bjöm Böhle

Top-down construction (or cut and cover construction) is providing important advantages when comparing with conventional construction techniques for commercial developments with deep basements, underground car parks or near surface infrastructure and traffic tunnels. Main features are substantially reduced restrictions to surface usage, avoidance of intervention with adjacent property, provision of rigid substructures resulting in minimal deforma­tions and settlements and, last but not least, accelerated construction pro­gramme. The present contribution illustrates the construction method in general and elaborates in detail on the special foundation works for a major urban commercial high rise development requiring a six level basement structure.

Jan 1, 2006

By Tracy Brettmann

The use of rock-socketed Augered Cast-In-Place (ACIP) piles is new to the Austin and central Texas region. This case history describes the design methodology, load test results, quality control procedures and the rate of production pile installation for the first large commercial project where ACIP piles were used in Austin. The piles were 24 inches in diameter and extended through about 45 ft of alluvial materials to be socketed 6 ft into limestone. A full-scale instrumented load test was performed on a test pile that was loaded to 452 tons and held for 24 hours. Telltales were installed in the middle and the tip of the test pile. As part of the overall quality control procedures, singlehole sonic integrity logging was performed on the production piles to verify structural integrity during pile installation. During pile production, an average of 14 piles per day were installed, which is approximately seven times faster than the original design that consisted of drilled shaft foundations.

Jan 1, 1998

By A. V. Shroff

The Indian Standards code of practice for design and construction of underreamed piles contains provision for installing such piles in expasive soils. In recent years, a large amount of research work has been carried out in the analysis, design, construction and performance of underreamed piles in expansive soils. This paper suggests that the results of this research field tests should be included in the code. Various additions and modifications as well as deletions that should be incorporated in the code are discussed.

Jan 1, 1996

By David J. Baxter

Use of bored displacement piles has experienced significant growth in the UK piling market sector, largely due to their environmental advantages over other piling methods and through cost benefits. Bored displacement piles are a cast-in-situ construction which can be formed with minimal production of spoil and offer low noise and vibration compared to driven displacement piles. A large variety of bored displacement piles have been developed. This paper describes a standard system for their classification. The development of the different types is described along with the factors which have led to their increased use. Consideration is given to processes undergone by the soil during pile installation and design approaches for bored displacement piles are compared. Comparisons are made between the different classifications of bored displacement pile. Comments are also made on the installation of such piles. It is concluded that complex changes occur in the stress states of the surrounding soils. Such effect of the pile installation on the soil should be accounted for and there is a need, therefore, to further refine the design process for these piles.

Jan 1, 2006