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By Timothy C. Siegel

Given that piles are composed of different materials and installed using a variety of methods, ASTM D 1143/D 1143M-07 Standard Test Methods for Deep Foundations Under Static Axial Compression is justifiably general so that it has as many applications as reasonably possible. There are aspects of the test setup, the test procedures, and data interpretation for instrumented piles (some of which are specific to augered cast-in-place piles) that are either not discussed in detail in this ASTM standard or are not addressed at all. Specifically, the use of variable time hold times can obscure the shape of the conventional load-deflection curve, as well as, influence the interpretation of the ultimate pile capacity. Unload-reload cycles induce additional non-uniform internal axial loads within the pile which complicate interpretation of the strain gage data and increase the potential for errors. Attempts to maintain a constant top load during the hold period can lead to operational difficulties in taking measurements and are technically unnecessary. Residual load has been shown to develop in cast-in-place piles and can significantly influence the axial load distribution as interpreted from strain gage data. The stiffness of cast-in-place piles has been observed to vary with the measured strain, and a constant modulus, as provided by correlation with the unconfined compressive strength of the grout, may lead to a significantly different interpretation of the axial load distribution.

Jan 1, 2010

By J. Racinais, P. Vincent

"In September 2011, Menard Oceania (MO) was engaged by Mac Mahon John Holland Joint Venture (MJHJV) to provide ground improvement solution for the $34bn Ichthys LNG development. With close to 400,000m2 of mangrove swampland set to be reclaimed and improved, this project was a great opportunity to showcase the technical, commercial and environmental benefits that Dynamic Replacement (DR) ground Improvement technique can provide. The ground improvement works involved complete design and construction for the Ichthys LNG site located at Blaydin Point on a low lying peninsula in Darwin Harbour. Dynamic replacement and stone columns technique were selected to treat intertidal mangrove mud to achieve required bearing strength, stability and limit settlement to an acceptable levels. The site is underlain by a 3m to 5m thick layer of highly organic mangrove muds with very soft shear strength ranging from 0kPa to 12kPa at depth. The site is exposed to daily sea water level tidal variations of up to 8m, which created significant constructability constraints and slope instability risks. This paper presents the design philosophy, the process involved in the selection of the construction methods, the site constraints encountered during the works and a review of the results achieved, quality control and post constructions performance.INTRODUCTIONInpex Browse, Ltd (Inpex) and its partner Total are developing the Ichthys gas field to pipe gas to onshore facilities at Blaydin Point on the south side of East Arm in Darwin Harbour. The proposed LNG plant consists of gas receiving facilities, 2 x 4.2Mtpa nominal capacity LNG trains, LPG and condensate production facilities, product storage and export facilities, a module offload facility (MOF), a flare pad (FP) and associated off plot facilities.The proposed on-shore facilities are located on extremely soft intertidal mangrove muds, therefore an appropriate ground improvement was required to achieve required strength and stability of site works and limit long term settlement to an acceptable level.Various ground improvement techniques were studied to select the most suitable for the ground conditions and site constraints encountered at the Blaydin point site. Dynamic replacement technique was selected for onshore section to improve soft mangrove mud to depths of 5.5m and Stone Columns (SC) technique was selected for MOF off-shore section to improve intertidal deposits to a depth of 2.5m.This paper presents DR design and construction works performed between December 2012 and August 2013 at Flare Pad Area."

Jan 1, 1900

By Francisco A. Flores, José L. Aguirre, Héctor A. de la Fuente, Erika Bernal, Jorge Arroyo-Esquedla

This paper presents the analysis, design, and construction of soil improvement for storage tanks foundation support at a site in Tabasco, Mexico. A total of 980 Rammed Aggregate Piers of 12.5 m in length and 0.5 m in diameter were designed and constructed to support four storage tanks. The soil conditions at the site generally consist of loose to medium dense silty/clayey sand to about 8m depth, underlain by very loose to medium dense silty/clayey sand with seams of very soft clay. The use of Rammed Aggregate Piers induced densification of the soil to increase its stiffness and reduce the liquefaction potential to control both static and dynamic induced settlements. Standard Penetration Test (SPT) and Cone Penetration Test (CPTu) explorations were performed prior to and post soil improvement to compare the liquefaction potential and the Factors of Safety associated with the two conditions. Finally, the soil improvement installation rate is presented. Soil improvement using Rammed Aggregate Piers represented a suitable alternative to support storage tanks foundation in potentially liquefiable areas.

Oct 1, 2022

By James Warner

Investigations of the sinkhole indicated that the loose, disturbed ground was completely encircled by dense competent core. This confinement substantially increased the effectiveness of the compaction grouting compared to what might have been expected at a "greenfield" site. However, the 8 ft diameter circle shown in the plan view was only the surface expression of the sinkhole proper and the deep, loosened ground actually extended to a larger diameter of about 20 ft. The planned spacing of the grout holes was based on the finite element simulations using a target void ratio of less than 0.3 throughout the compacted ground within a 5 ft radius of the grout injection point. Because of the strong confinement effect, the layout of grout holes included one central primary hole surrounded by six secondary holes at a triangular spacing of about 5 ft. Since the disturbed ground was considered a confined cylinder, it was anticipated that the primary hole would perform the majority of work and the secondary holes would act as check holes, with progressively lesser grout takes as the loose ground densified.

Feb 10, 2003

By Shahriar Vahdani, Andy Herlache, Andrew Bro, Wei-Yu Chen

"The Presidio Parkway Project will reconstruct approximately 1.6 miles of highway, including seven bridges, three cut-and-cover tunnels, and an undercrossing connecting the Golden Gate Bridge to the City of San Francisco, California. The project site is approximately 5.6 miles from the San Andreas Fault, which is capable of producing magnitude 8 earthquakes. Seismic hazards include strong ground shaking, soil liquefaction, ground settlement, and lateral spreading. At the Tennessee Hollow bridge section up to 30 feet of loose sands and soft clays are present. Concerns are raised that standalone drilled piers will experience excessive lateral soil loads from liquefaction-induced lateral spreading pressure resulting in excessive pier head displacement of up to 8 inches. Ground improvement by Cement Deep Soil Mixing (CDSM) is proposed to provide additional foundation stiffness. This paper presents the methodology to: 1) assess the effectiveness of the ground improvement in resisting lateral spreading, and 2) optimize ground improvement design at individual bridge bents based on local site condition. A series of 3-D numerical analyses are conducted and the results show that drilled piers with CDSM ground improvement are capable of withstanding seismic demands from lateral spreading and the lateral pier head displacement is reduced to less than 2 inches. The adopted analytical approach is efficient at modifying design for individual bents and can be considered for future pier foundation design in seismically active areas. IntroductionThe Tennessee Hollow bridge section (Low Viaduct) is an integral component of the Presidio Parkway project which will replace the existing facility with a new multi-lane roadway between the Golden Gate Bridge and the City of San Francisco. As shown on Figure 1, the project site is located about 5.6 miles east of the San Andreas Fault and 12.5 miles west of the Hayward Fault. The Low Viaduct will span over a future wetland habitat subject to tidal fluctuations and potential scouring."

Jan 1, 2014

By Rimas Veitas, James Panton, Erich Steinlechner

"Ductile Iron Piles (DIPs) are a proven, viable alternative to conventional piles, and for the past five years have been successfully used throughout New England. The installation process of DIPs lends itself to both large and small projects. Because of their installation efficiency they provide a substantial cost savings over drilled micro piles. Several New England projects (both end bearing and friction) will be evaluated, focusing on the installation and design procedures.BackgroundThe driven ductile cast iron pile (DIP) is a simple, fast and highly effective pile system. Over the last 30 years over 10 million feet of this pile system has been installed worldwide predominantly in Europe. DIPs are a prefabricated driven pile system utilizing high strength ductile iron pipes which are manufactured using a spun-cast process having outside diameters of 4 5/8” and 6 5/8 inches. The standard pile lengths are 16.4 feet long. The pipes are manufactured with a tapered socket with an internal shoulder for full engagement at the top and a tapered spigot at the bottom. The individual pile sections can be connected with this Plug and Drive® connection to drive a pile of any length.(see figure 1)The DIP system’s inherent advantage is the simplicity of the installation process. The piles are driven to refusal or to a required penetration depth with the use of a high-impact highfrequency hydraulic hammer (ie. Breaker hammer). In most applications the hydraulic hammer is mounted on an appropriately sized excavator (see Photo 2). At the completion of driving the pile, the pile is cut off (see photo 5) and the remaining section of pile is fitted with the appropriate driving shoe and serves as the lead section for the next pile. Being able to reuse the cut off section, yields minimal if any pile shaft waste. The pile is then fitted with an appropriate pile cap plate to receive the load from the superstructure."

Jan 1, 2017

By Patrick J. Hannigan

The pile foundation designer typically performs a subsurface exploration program and static pile capacity calculations before selecting a pile foundation type, length, and capacity. During construction, a pile installation criterion must be established to meet these design requirements. This installation criterion usually consists of a minimum penetration resistance or blow count to confirm pile capacity and may also include a minimum embedment requirement. This text will focus on use of wave equation analysis and dynamic measurements to meet design requirements. BEFORE THE WAVE EQUATION Since the mid-1800s, over 450 dynamic formulas for pile driving control have proliferated. In their simplest form, these formulas relate hammer energy to the work of soil resistance, or simply: W ? h = R ? s (1) Where W = ram weight h = ram drop height or stroke R = pile capacity s = pile penetration per blow

Jan 1, 1990

By Edmund J. Cardoza

WELCOME TO THE DEEP FOUNDATIONS INSTITUTE 26TH ANNUAL CONFERENCE AND WELCOME ESPECIALLY TO THIS SEMINAR ON NON-DESTRUCTIVE TESTING OF DRILLED SHAFTS, PRESENTED BY MEMBERS OF THE DFI DRILLED SHAFT COMMITTEE. MY NAME IS ED CARDOZA; I AM A VICE PRESIDENT WITH THE MILLGARD CORPORATION, A DRILLED SHAFT CONSTRUCTOR FOCUSING PRIMARLY IN THE EASTERN HALF OF THE UNITED STATES.

Jan 1, 2001

By Lance Rasband, Richard Hanke, John Starcevich

"The 17.4 meter (57 ft) diameter tunnel boring machine (TBM), the world’s largest at the time of her launch in 2012, locally referred to as “Bertha,” is stuck. Incapacitated due to mechanical failure approximately 36 meters (120 ft) beneath downtown Seattle, situated precariously between the deteriorating Alaskan Way Viaduct and the failing Seattle Seawall. Accessing Bertha with a vertical shaft provides the best approach to address all facets needed for repairs and will allow the full removal of Bertha’s cutter head and related inner workings. Limited area above the tunnel alignment and the physical restrictions of existing infrastructure, create significant challenges for the design of an otherwise symmetrical shaft, requiring special attention to design and layout. Consequently, the access/recovery shaft design required a combination of 3m, 2.5m, 2.2m, 1.5m and 1m diameter unreinforced drilled secant piles coupled with various ground improvement techniques and dewatering, to fully satisfy the shoring design requirements. This paper will describe the shaft installation procedures, equipment used and pitfalls encountered while undertaking access shaft construction of this magnitude.INTRODUCTIONTunneling on Seattle’s SR99 tunnel project began in July of 2013. After slowly mining through a 4.5 m (14.76 ft) thick fiber-reinforced concrete headwall and the first of three stabilized “safe havens,” Bertha would proceed along the proposed alignment through 122 meters (400 ft) of jet grout improved soil at a rate of slightly over 1.6 m (5.25 ft) per day. Once past the improved area, it was planned that “Bertha” – would be moving at a rate of about 11 m (36 ft) per day. By the end of October 2013, Bertha had mined roughly 131 m, (430 ft) averaging 1.4 m (4.6 ft) per day and had begun mining within native soils. By December 2013, tunneling had reached the 244 m mark and Bertha was averaging 3.6 m (11.8 ft) per day, achieving as much as 12.8 m (42 ft) of progress on given days. Unfortunately, on December 6th, 2013, Bertha began to stumble and all progress quickly came to a halt.It was initially reported that an obstruction had stopped Bertha in her tracks. The preliminary investigation involved installation of 10 deep dewatering wells to reduce the hydrostatic pressure around the TBM, and allow visual inspection of the cutter head from within the TBM, and also to investigate for the presence of obstructions at the face of the cutter head. During this inspection, fragments of steel pipe were discovered entangled in the cutter head. The fragments were apparently from an abandoned 254 mm (10 in.) diameter monitoring well casing, previously installed by WSDOT to monitor ground water conditions for the design and planning of this tunnel project. After the steel was removed from the cutter head and cleared from Bertha’s path, tunneling resumed. It was then discovered that Bertha was only able to generate a slow crawl."

Jan 1, 2016

By K. Ronald Chapman, Claus Ludwig, Doug Jenevein

"In the spring of 2005 Schnabel Foundation Company completed a $15.2 million Design/Build subcontract to underpin 11 structures, and provide 202,800 square feet of earth retention for the Reno Transportation Rail Access Corridor (ReTRAC) project in Reno, Nevada. Schnabel’s work was part of a Design/Build contract to depress a railroad alignment through downtown Reno. The depressed section was 2.2 miles long, 54 ft wide, and up to 35 ft deep (3.5 km long, 16.5m wide and up to 10.7m deep). The trench structure was required to be watertight. SUBCONTRACT WORK OVERVIEWEleven buildings along the track alignment required underpinning. Three types of underpinning were used, designated Type 1, Type 2 and Type 3.At four buildings the trench retaining walls were to be located directly under the exterior footings. This alignment eliminated traditional underpinning and cut-off wall techniques that could normally be used to support structures. Type 1 underpinning was used at these buildings. This underpinning system consisted of a combination of permeation grouting, hand-dug piers, and permanent tiebacks. This underpinning system became the new watertight trench walls.Five buildings were located a few feet behind the trench walls, and their exterior walls were supported by continuous footings. Type 2 micropile/pile cap underpinning (patent pending) was used to support these buildings.The remaining two buildings were also located a few feet behind the trench walls, but they had column footings along the exterior walls. At these structures traditional micropile underpinning was provided through the existing footings. This is described as Type 3 underpinning.Temporary earth retention was required on both sides of the trench along most of the alignment. This shoring supported frontage roads, private property and surcharge from the temporary railroad shoofly running parallel to one side of the trench.SUBSURFACE CONDITIONSThe soil along the trench alignment consisted of river outwash deposits. The top 2 to 18 feet (0.6m to 5.5m) generally consisted of flood plain silt and sand deposits, or fine-grained fills. These fine-grained soils are underlain by the Tahoe Outwash Formation which consists of interbedded layers of sand; sand and gravel; and sand, gravel, cobbles and boulders. Some of these layers encountered during construction consisted of 30 to 50 percent cobbles and boulders, with some boulders up to eight feet in diameter.A major challenge to the design and construction of the trench structures and the underpinning was the ground water table which was 10 feet (3m) above subgrade in the deepest portions of the trench. Based on specification restrictions, temporary and permanent dewatering was not feasible. As a result, the selected design and construction methods had to consider three water conditions: the anticipated groundwater level during construction (CGW), the groundwater level for permanent design (DGW), and an additional special design condition with water at street grade."

Jan 1, 2006

By Cemal Can Maslak, Vijaya Bhushan Rao, Vidyaranya Bandi, Karsten Beckhaus

A Large Earth Cum Rock Fill, ECRF Dam is under construction at Polavaram in the state of Andhra Pradesh in India as part of an irrigation project. The Embankment crest width of the dam is 12.5m and base width is of approximately 136.75m with a stepped sloping height of 27m on both upstream/downstream sides. Once the 1.2m Thick Plastic concrete cut-off wall is constructed below the dam along the longitudinal central axis to avoid seepage, this magnificent structure will be supported on a series of Deep Mixing Columns and Stone Columns that are evenly arranged under the footprint of ECRF Dam forming a smooth transition of gradually reducing stiffness moduli of treated ground from the center of the embankment, where the foundation stresses are high, towards the edges in order to be able to progressively limit the settlements under the dam to a specified allowable limit. As such the required post treatment stiffness in case of stone columns is 2 times of the in-situ stiffness of foundation soil, whereas it is expected to be 5 times improvement for Deep Mixing as per project specifications. Laboratory testing and Field Trials undertaken successfully to verify the design.

Sep 1, 2022

By Karen Dawson

This paper presents a case study of the deformation-based design, construction, and performance of stone column ground improvement (GI) beneath a mechanically stabilized earth (MSE) wall and bridge abutment with heights up to 50 feet. As part of the widening of Interstate 5 (I-5) to allow High Occupancy Vehicle (HOV) lanes in Tacoma, Washington, a new approach and span over the Puyallup River will be constructed. During the soils investigation and design phase of the project, low plasticity silts (ML) inter- bedded with silty sand layers and organic silt where identified as being potentially liquefiable. Stone column ground improvement was designed using a deformation-based approach to address static settlement and seismic stability of the proposed MSE embankments. The deformation-based design of the stone columns resulted in significant savings over a limit equilibrium-based approach. This paper presents the results of sonic coring taken from the initial stone columns installed and compares these results to the real-time data acquisition reports from the stone column installations. Vibration monitoring results during stone column installation are included. Settlement monitoring at the face of the MSE wall and buried vibrating wire settlement monitoring elements are presented and compared to the original settlement predictions.

By Reda Mikhail, M. Birkan Bayrak

The Washington State Department of Transportation (WSDOT) State Route (SR) 167/70th Avenue East Vicinity Bridge Replacement Design-Build project is located in Fife, Washington. This $40 million project consists of replacing the existing 70th Avenue Bridge over Interstate 5 (I-5) with a single-span bridge of about 220 feet long with approach embankments. The subsurface conditions along the new bridge alignment generally consists of alluvial deposits with high potential of liquefaction overlying glacially overridden deposits. In the early stages of the project, drilled shafts were considered as the deep foundation system; however, after an additional subsurface investigation is completed at the site, driven pipe piles were selected as the deep foundation system. Bridge abutments are supported by 24-inch diameter, 80-foot-long open-end driven steel pipe piles. The pile length was determined to bypass a relatively thick liquefiable zone and to tip the piles above what could be compressible soils. The use of advanced seismic analysis was instrumental in optimizing the pile length. The dynamic testing performed on numerous piles indicated what could be unique soil setup factors compared to those measured in local projects as well as those reported in national design manuals. Detailed discussions of the pile foundations design and construction is presented in this paper.

Sep 8, 2021

By John P. Briand III, Douglas J. Aghjayan, Robert E. Fosse

This paper highlights the successful pile load testing program for the redevelopment of Pier One in East Boston, Massachusetts. Pier One is a 5.4-acre parcel on a dormant waterfront site used in the 1950s as a warehouse and distribution facility. The developer plans to re-use the existing 14-inch-diameter concrete-filled steel pipe piles to support four 5- to 7-story apartment buildings above a 2-story parking garage. A pile load testing program was developed to establish if the existing piles could support design loads of 240 kips for project financial feasibility and up to 300 kips for a significant reduction in future foundation costs. The Phase 1 program consisted of statnamic and dynamic load testing on two piles with two loading intervals (200 and 240 kips). Based upon the favorable results of the Phase 1 program, the Phase 2 program involved statnamic load testing on two piles and dynamic load testing on ten piles with three loading intervals (200, 240, and 300 kips). The Phase 2 program confirmed the favorable results which were applied across varying strata thicknesses and pile embedment depths. The average allowable capacity for the piles tested was greater than 300 kips with pile movement up to 0.3 inches.

By James G. Ulinski, Sebastian Lobo-Guerrero, Vishal B. Patel

"Recently modified design equations used in the transportation industry to calculate side friction and end bearing capacity for drilled shafts are now providing more realistic estimations of capacities than did previous methods. Using multiple case studies and test results from various projects, a more realistic design approach was formulated by the Federal Highway Administration (FHWA), which resulted in greater values of ultimate capacity for side friction and end bearing and in a more efficient design overall.In 2010, the FHWA published GEC-10 – Drilled Shafts: Construction Procedures and LRFD Design Methods, which illustrates a different method of calculating side friction and end bearing resistance and results in greater values for design. In 2014, the Association of State Highway and Transportation Officials (AASHTO) adopted the method put forth by FHWA, which was included in its LRFD Bridge Design th Specifications, 7 Edition. The Pennsylvania Department of Transportation (PennDOT) recently adopted and incorporated the similar methodology as AASHTO for calculating side friction and end bearing for drilled shafts in rock, and these changes are reflected in the 2015 edition of the PennDOT Design Manual, Part 4 (DM-4). This article discusses the past and current design methodology along with a project case study with results from Osterberg Cell (O-cell) load testing, which presents a comparison between the design resistances of ultimate side friction and end bearing and the measured capacities at failure.The Old and the NewEditions of the AASHTO LRFD Bridge Design Manual from 2012 and earlier estimated ultimate side resistance, qs, in rock using the following equation (modified from Horvath and Kenney, 1979):qs=0.65aEpa(qu/pa)0.5 < 7.8pa(f ’c/pa)0.5 where: qu is the uniaxial compressive strength of the rock in ksf; pa is the atmospheric pressure in ksf; aE is the reduction factor to account for jointing in rock; and f ’c is the compressive strength of the concrete in ksi. For intact rock, previous versions of the AASHTO manual required that the ultimate end bearing resistance, qp, was calculated using the following equation: qp=2.5qu."

Jan 1, 2017

By William Billiet

"The Dulles Silver Line Phase II is an 11.4 mile extension of the Washington Area Metro Transit Authority’s Silver line in northern Virginia. There are three miles of elevated guideway, which are supported on 188 large diameter mono-shafts founded within the Triassic Geologic Aged Culpeper Fault Basin. Three lateral load tests were performed on fully instrumented test shafts. The challenge in developing the load testing program was how to reproduce the effects of the extremely high design loads along the test shafts, considering the limitations of the load test equipment. Development, execution, and analysis of the lateral load test program is discussed.INTRODUCTIONPlans for Dulles Silver Line Phase II include two Aerial Guideway sections on elevated track, the Main Line and Yard Leads. The Aerial Guideways are supported on mono-shafts (single, largediameter drilled shafts) socketed into rock. Lateral loads are resisted primarily through the stiffness of the shaft and the geotechnical resistance of the rock socket. The monoshafts were designed in accordance with AASHTO LRFD 2014. Based on our preliminary analyses, the production mono shafts were expected to consist of 6.5, 7.5, and 8.5 foot diameter drilled shafts with rock socket lengths varying between 8 and 34 feet (averaging 14 feet). Table 1 summarizes the maximum service load combinations for each size production shaft along the aerial guideway alignment.GEOLOGYThe project is located within the Piedmont Province, a major physiographic province on the east coast of the USA extending from Alabama to Pennsylvania. Within the Piedmont, a number of Mesozoic basins formed in rift valleys. Dulles Airport is located in the Culpeper Basin, characterized by a relatively shallow siltstone rock surface compared to the adjacent areas underlain by Piedmont crystalline rocks. The geologic stratigraphy at the load test sites generally consist of residual soils and intermediate geo-material (IGM) overlying siltstone rock. IGM is a term used by Virginia Department of Transportation (VDOT) to describe residual material as it transitions between soil and rock. For the purposes of the load test, the siltstone rock is classified as fractured rock (RQD<50), and competent rock (RQD=50). Table 2 summarizes the stratigraphy encountered at each test site."

Jan 1, 2017

By Unnikrishnan Nair, Sandeep S. Nikam, Sanjay D. Patil, Prabir C. Basu

"Mumbai Metropolitan Region Development Authority (MMRDA) entrusted to implement Monorail Systems in various parts of Mumbai Metropolitan Region (MMR) with the objective to supplement the present transport system in MMR. The stretch of Monorail is starting from Sant Gadge Maharaj Chowk (SGMC) and extending up to Chembur Railway Station, divided into 2 phases. Construction of Phase 1 (Chembur to Wadala Depot) is complete and Phase 2 (Wadala Depot to SGMC) is under construction.Monorail runs on prestressed girder (guide beam) of span ranging from 20m to 28m supported on pier founded upon group of end bearing piles embedded in rock, pile group ranging from 2-4 piles of diameter 1000mm each.For the purpose of site characterization, geo-technical investigations were carried out along the alignment of Monorail system as mentioned above. These investigations included field and laboratory tests. The subsurface strata mainly consist of silty sand, gravel, underlain by marine clay extending up to stronger basalt rock with volcanic breccia. Overburden consisting of mainly marine clay ranging from 5.5m to 11m at all locations within the influence zone of settlement.The existing rigid pavement along of Sion-Koliwada and Anik-Wadala were constructed about 5 years prior to the construction of Monorail piers. Before laying the rigid pavement, to improve the geotechnical strength of subsoil (mainly marine clay), ground improvement using stone columns was undertaken by MMRDA. In light of limited right of way, the Monorail piers have been constructed in the median portion of the road. The line became operational on February 2014, in few months it was noticed that, in the vicinity of the Monorail piers, along Sion-Koliwada link and Anik-Wadala link, the Road Pavement Quality Concrete (PQC) panels adjacent to the Monorail piers started showing distress in form of nonuniform settlement of the concrete panels.Effect of pile foundation on pavements/PQC slab distress and possible causes of distress were investigated. Initially the distress was thought to be upheaval of monorail pier cap, but further investigations revealed the same to be soil settlement occurring over time. This paper describes the investigation carried out for identifying the cause of this settlement."

Jan 1, 2015

By Mikael Calando, Thomas Joussellin

"San Francisco's rapid growth has caused the city to plan for the Transbay Transit Center Project, a visionary transportation and housing project, that will transform downtown San Francisco and the San Francisco Bay Area’s regional transportation system by creating a “Grand Central Station of the West” in the heart of a new transit-friendly neighborhood that will be home to more than 20 new towers rising a high a 1,070 ft. This paper describes the specificities of using advanced diaphragm wall technology, tooling, equipment and installation practices for deep foundation and permanent underground structures. In particular, this paper will emphasize on the urban constraints, geotechnical conditions, and the novel approaches adopted for the construction challenges of the Transbay Transit Center’s Load Bearing Elements, or Barrette PilesPaperThe Transbay Transit Center Project consists of the construction of a new multimodal, five-story Transit Center located in the South of Market neighborhood near the Financial District in San Francisco. The future Transit Center will incorporate nearly 83,000 square feet of retail, a 5.4-acre rooftop park, an extensive public arts program and bus ramps that will connect the Transit Center to a new off-site bus storage facility and the San Francisco–Oakland Bay Bridge. The new facility will accommodate more than 100,000 passengers each weekday and up to 45 million per year. Additionally, the new Transbay Transit Center will replace the since-demolished San Francisco Transbay Terminal, and nearly 20 towers, such as Salesforce Tower, will take advantage of the height increases allowed through the Transit Center District Plan.The approximately $4.5 billion project features a new five-story structure (including two underground stories) and new bus ramps which include a cable-stay bridge. The deep foundations for the pylon of the bridge (Pylon 9) consist of two each 21 ft x 5 ft barrettes (also called Load Bearing Elements in the US) extending more than 180 feet below grade and 10 feet into the bedrock. The barrettes were chosen because of the combination of high loads, significant depth and small footprint. The barrettes are installed using the Diaphragm Wall technology. Nicholson Construction was contracted by Shimmick Construction to install the cable-stay bridge’s foundation elements."

Jan 1, 2016

By Michael Moran

Typical ACIP Pile Rig [ ] Hollow Stem Auger ? Continuous flight auger ? 3 inch inside diameter pipe ? Auger diameters: 12, 14, 16, 18, 20, 22, 24, 30, and 36 inches ? Auger section lengths: 4, 5, 10, and 20 ft ? Weight ranges from about 70 lbs per ft for 12 inch to 120 lbs per ft for 24 inch and 200 lbs per ft for 36 inch

Jan 1, 2005

By Sumantra Sengupta

"Northeast Frontier Railway (NF Railway) intends to connect Imphal, the capital of Manipur (bordering Myanmar) with Assam by railway link. They have planned a 125km long railway line that passes through steep rolling hills of Patkai region, eastern trail of Himalaya, and as a result large number of tunnels and bridges need to be designed. While the high mountains are penetrated by tunnel, the deep gorges between the mountain ridges are connected by tall bridges. The tallest of such bridges connects a gorge at about 140m above its bed level with an overall length about 700m at rail level. In all, five such bridges with tall piers are now under construction. With extensive study on possible alternate arrangement of the bridges considering the effect of high seismicity of the area, moderately to highly weathered siltstone/ sandstone as ground bed material, slope of the hills etc it was decided that bridge will be founded on 1.5m diameter bored cast in situ piles with length varying from 20m to 30m depending on the location. The substructures are RCC hollow pier and superstructures are steel open web through type girder of 103.5m span. Considering absence of any major construction work in the vicinity, it was decided that prior to design work, Site-specific spectrum study will be carried out and design will be carried out considering the varying stiffness of the tall piers, each of different height. Interesting results were obtained regarding behavior of piles under lateral loads generated by high seismic conditions. The paper discusses in detail the design of Pile foundations and the effect of bed material along the steep slope on which the piles are being constructed.INTRODUCTIONIndian Railway has undertaken the construction work of connecting the North-Eastern states of India through railway line. The major stretches of the area passes through hilly terrain and as a result the line passes through tunnels and bridges in succession. The tall mountains are being penetrated with tunnels and immediate after deep gorges are crossed with high level bridges. The entire area is under high seismically active zone. The bed material below the ground level of the sloped hill is 4 to 10 meter of mixed soil of sand, gravel, pebbles etc underlain by moderately to highly weathered sandstone, siltstone at the higher level and moderately weathered sandstone, siltstone at lower level. Considering all the aspects like constructability, maintainability, geological and geotechnical aspect, seismicity, stability, safety, functional aspect and cost it was finally decided that the bridges will be simply supported structure with open web through type steel superstructure of maximum span 103.5m and hollow cylindrical discretely varying RCC substructure with 1.5m diameter group of piles as foundation. The paper discusses on the design aspect of the pile foundation in the rocky strata in the hill slope. The codes and standards that have been followed for design are IRS (Indian Railway Standard), IS (Indian Standard), IRC (Indian Road Congress), AREMA (American Railway Engineering and Maintenance-of-way Association), UIC (International Union of Railway) provisions."

Jan 1, 2015