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By Jon E. Bischoff

Construction of a secondary clarifier on the banks of Rainy River, Northern Minnesota, required the driving of H-piles 14HP102 to a sloping, very strong bedrock through thick deposits of soft and medium stiff soils. Pile toe protection, APF Hardbite HP 77750, was specified to prevent damage to the pile toe and to enable the pile toe to bite into the bedrock surface. The toe protection worked well for bedrock sloping less than 2H:1V. However, where the bedrock was steeper, the piles experienced damage and failed to reach bearing. In most cases, the also the replacement pile failed. Pile Driving Analyzer measurements showed that on encountering the bedrock, the pile toe reflection, which at first was sound, deteriorated indicating pile toe damage. Extraction for visual inspection showed that the failed piles were bent and had deformed pile shoes. In areas of steeply sloping bedrock and for replacement piles, an alternative shoe, the Scanpile Herkules rock shoe, was employed. This pile shoe proved to be able to secure the pile toe into the rock and to eliminate the problem. The costs of the Herkules rock shoe considering price, shipping, and attaching, were about equal with the Hardbite shoe.

Jan 1, 1993

By Larry D. Olson

Research, hardware development, and field testing have been conducted on systems to allow easy and accurate determination of both foundation tip depth as well as the properties of the soils at and above the foundation tip. The nondestructive testing method used for tip depth determination is the Parallel Seismic (PS) method, while the soil properties are determined by a Cone Penetrometer Test (CPT). The research and development effort reported herein uses a novel combination of the two methods to allow a single piece of portable field equipment to perform both tests. A system has been developed and tested that includes a triaxial geophone and a hydrophone in the cone probe tip to allow collection of the PS data by a CPT rig without requiring a drill rig with hollow stem augers. Using the instrumented tip along with a standard instrumented CPT cone allows for the simultaneous determination of both the depth of unknown foundations and the measurement of soil properties along the length of the unknown foundation. The combined system allows for a more complete and accurate analysis of foundation capacity and scour susceptibility.

Jan 1, 2007

By Alberto Carmona Rosell, Sri Ram Ramankutty

"The installation of Bored Piles and Diaphragm Wall under slurry using tremie raises quality concerns on the integrity of concrete. It is vital to understand the effects on concrete integrity during concrete pouring process. This paper intends to unveil to what extent the compressive strength of the concrete pour is affected in contact with drilling fluid still. Another important angle of analysis proves whether the inclusion of solids particles of un-hydrated fluid could have impact on the concrete compressive strength. The testing comparing the response of concrete compressive strength when drilling fluid is included into the concrete mix altering the water/cement ratio by 5%, 20% and 30%. Comparative results are analysed between two different hydrated slurries namely sodium activated Bentonite and 3rd generation synthetic polymer.1. INTRODUCTIONSoil stabilization is the base for a successful deep foundation execution. The G3 System Slurry developed by Ground Engineering Operations (GEO), with its third generation polymer, namely PolyMud®, is an innovative and unique alternative to the mineral based slurries for soil stabilization, enhancing the quality and integrity of the underground foundation structures. It optimises the production rate of work progress and cost as well. At the same time, PolyMud® slurry is proven to be environmentally friendly.Guaranteeing the maximum quality of the foundation elements according to the initial design is one of the most important objectives and a concern for the foundations contractors. In order to fulfil the project expectations in this aspect, any incident that could compromise the designed concrete integrity and capacity must be avoided.GEO, has carry out its own research regarding effects on the concrete compression results if drilling fluid intermixes with fresh concrete while pouring. To shed light in this regard, GEO, in collaboration with CML (Concrete Materials Laboratory) Sdn. Bhd., carried out empiric tests that analyse this particular event from different perspectives, bringing up the corresponding results that will be studied and commented in this article."

Jan 1, 2015

By F. Keith Jacobson

To be involved in the construction of a deep dredged caisson for a major bridge pier is one of the most rewarding and professionally challenging experiences one can have in the bridge construction business. That experience was doubled in the construction of the two deep dredged caissons for the Highway 82 Bridge over the Mississippi River near Greenville, Mississippi. The challenges and the construction risks associated with constructing these two dredged caisson pier foundations highlight the construction engineering innovation associated with major bridge pier construction. The 1,378-foot Main Span of the Highway 82 Bridge makes it the longest cable stayed bridge span over the inland rivers of the United States. The main piers for this bridge are supported on two dredged caissons measuring 80-feet by 122-feet in plan, founding 200-feet and 170-feet below the river surface. The challenges of constructing these caisson structures, sinking them through 70-feet of water to the river bottom and then excavating and further sinking them to the founding grade without exceeding the design tolerances, were enormous. The construction engineering opportunities for innovation included major breakwater structures to create a friendly environment in 11 ft/sec currents, the first time use of Articulated Concrete Mattresses for river bottom scour control, unique air dome design to maximize the buoyancy of the caisson structure while floating, a caisson guide system to assure positive control and positioning of the caisson during the initial sinking phases, and a comprehensive sinking plan to assure maximum control and minimum risk. Many of the innovative solutions to the construction challenges on this bridge will be incorporated into future caisson construction projects on the lower Mississippi River.

Jan 1, 2013

By Edwin W. Hickey

This paper briefly discusses the geologic conditions in South Florida relative to the design, construction, and performance of deep foundations. The subsurface conditions in this area are unique in that the rock layers are highly porous and often very soft, and are sandwiched between layers of typically loose, uncemented quartz fine sands. Due to the high porosity of the Miami Limestone, 4-inch diameter rock coring is often required to obtain intact samples, and dewatering of excavations is sometimes difficult or impossible. The sand layers, typically tens of feet thick, are very loose to loose in relative density and have been the cause of unexpected large, deep foundation settlements. The engineering properties of the various geologic formations are discussed, along with typical deep foundation types used in the Miami area prior to and after 1980.

Jan 1, 2003

By Abid Adekunte

Traditionally, designers and contractors provide additional external supports to retaining walls through the use of tie-back anchors or braces. Both approaches are known to have their shortcomings; braces limit working space within excavation areas, while tie-backs are seldom used in built-up areas where intrusion into adjacent property of non-cooperative owners has to be avoided or in situations where sensitive structures exist behind the wall. This paper focuses on the design, construction and monitoring of deep excavation support systems on two separate projects located in different ground conditions in the Republic of Ireland. On both projects, conventional ground anchorage and propping were inapplicable. This led to the development and application of two different novel solutions on both projects. Methods of wall performance monitoring on both sites also differ. Wall monitoring results show these innovative methods to be safe and effective. Advantages of the novel solutions over traditional approaches are highlighted.

Jan 1, 2010

By G. Ranjan

The designers and the practicing engineers have started using latest and cost effective techniques of ground improvements which utilise the weak and poor sub-soil deposits efficiently for the civil engineering construction. In the present investigation, a new concept of 'skirted granular piles' has been advocated. An effective method of construction of granular piles as an economical alternative to vibroflot, and the skirt has been developed. The construction technique is based on indigeneous know how which effectively utilises the man-power technology avoiding import of costly equipment suiting to the developing countries. Full scale insitu tests have been carried out at four sites, having different soil conditions, on virgin weak sub-soil, and improved ground by casting plain and skirted granular piles. Effectiveness of different types of skirt has been demonstrated through insitu tests. A simple analytical approach has been proposed to predict the ultimate pile capacity. The predicted values of ultimate capacity have been found to demonstrate a good correspondance. Granular pile behaviour in terms of pile depth, diameter, spacing and stress deformation characteristics of the improved ground have been discussed. A significant improvement in ultimate capacity in improved ground has been noted. This is further augmented when granular pile group is skirted.

Jan 1, 2010

By Douglas L. Scaggs

Driving piles in under water applications has become more common place over the past twenty years. Where only a water depth reachable with a follower or dewatered cofferdam was the rule in the past, newer technologies developed for the offshore oil and gas industry have made depths of even several thousand feet possible offering new possibilities in foundation design and installation. With the new technology, engineers can now more efficiently design structures by placing foundations optimally thereby reducing weight and cost of the overall structure.

Jan 1, 2013

By Ambarish Ghosh, Subhaprasad Chakraborty

"Construction of basement floors has become necessary to meet the requirement of parking in office and residential complexes and in hospitals for radiotherapy treatment. Important projects coming up in Kolkata are mostly in closer proximity of residential buildings, office buildings and historical monuments. Sheet piling is mostly used as temporary shoring system during construction. Deep excavation in urban environment creates great problem related to construction induced vibration due to driving of sheet piles for basement, pile driving etc. which raises the chances of damage of adjacent buildings and nearby structures. Vibratory sheet-pile driving is the most common method of sheet pile installation. The knowledge of induced vibration due to this phenomenon is still very deficient. This paper presents the analysis of measured vibration data collected from different sites of Kolkata with varying soil profile. Typical two case studies of sheet pile and pile driving has been presented and the vibration values are analysed. The responses of the vibration are reported in terms of peak particle velocities (PPV). To evaluate the effects of vibration due to pile driving two aspects have been considered: the effect of the energy entering the ground from the pile and the effect of the soil condition.INTRODUCTIONIn urban areas infrastructure development projects are mainly located adjacent to existing structures like residential buildings, offices and historical structures. The construction work of such project influences the surrounding environment as well as human perception (Wiss 1981). During the construction of basement for residential complexes and hospitals sheet piling is mostly used as temporary shoring system or as to support the earth mass. The vibration induced due to driving of piles and sheet piles have been presented herein. Deep excavation projects close to existing structures increase the concern of environmental impact. For this reason the vibration assessment and prediction has become a subject of great interest. It is important to develop a site specific model for predicting the ground vibration resulting from pile and sheet pile driving at the construction sites. The developed model gives the efficacy to guide the engineer to select the construction methodology ensuring the safety of the surrounding structure. The model developed here is site specific and the parameters that has been used are dependent on the soil condition and the energy source."

Jan 1, 2015

By Tomio Tsuchiya

A construction method of bored steel H piles enclosed in soil-cement columns was developed by modifying steel H piles from the driven pile method and soil-cement walls from the earth retaining wall method, the latter of which produces cut-off walls and reduces noise and vibration during construction. In this method, as shown in Figure 1, rich mix cement paste is injected into the bottom of a borehole which is pre-excavated by a casing auger, then a steel H beam is inserted before it hardens. Since the high vertical resistance of piles created with this method has already been confirmed by loading tests, we have been investigating the applicability of this method for piles used to temporarily support building loads for top-down construction on raft foundations until the raft foundation is completed. However, in the loading tests, the bearing capacity at the lower end of the pile was measured by loading from ground surface on test piles which had friction cut to eliminate the shaft friction resistance. In other words, the loading tests neglected the effect of overburden pressure of soil above the lower end of the pile. To investigate the effect of the overburden pressure on the bearing capacity at the lower end of the pile, loading tests were carried out on a bored steel H pile of lm diameter (test pile) bored in a compacted sandy soil layer with N-value of 100 to 250 at each stage of a three-step excavation. The results show no significant change in the bearing capacity at the lower end of the pile when the depth ratio of the pile is in the range of 5.7 to 22.7.

Jan 1, 1996

By Peter J. Nicholson

Recognition of the liquefaction susceptibility of dam embankments has been heightened since the San Fernando Dam near failure incident in 1971. Both the downstream and upstream slopes of dams can be at risk for slope failure that can lead to breaching of the dam during or after a seismic event. Many dams have been remediated by various means such as the installation of stone columns or by excavation and replacement of the liquefaction susceptible material. Recent engineering and technology advances in equipment and materials has shown that construction of shear walls to the appropriate depths and at the right center to center spacing may be an economical alternative to the more traditional methods. Recently, the downstream embankments of at least 4 dams, from South Carolina to California, have been, or in the process of being remediated by the use of shear walls. The method of installation has been either multi-axis Cement Deep Soil Mixing walls or walls constructed by the use of trench excavation under self-hardening slurry. Four case histories of dam remediation are discussed, three by multi-axis paddle auger CDSM equipment one with the use of self hardening slurry trenches.

Jan 1, 2008

By M. Meckkey El Sharnouby

In this paper, the results of full-scale field testing of reinforced helical pulldown micropiles (RG-HSP) installed in clayey till soils and resting on sandy soils are presented. Piles were tested under monotonic and two way cyclic lateral loadings. Effect of different loading setups on the results is demonstrated. The factors affecting the piles' performance are discussed. It was found that under monotonic loading the piles were able to sustain displacement up to 50% of the grout shaft diameter. Under low cyclic loading levels, the piles did not suffer degradation in the performance. Also, the degradation rate during cyclic loading increased with the increase of the load level. The experimental results show that the reinforced helical pulldown micropile is a reliable foundation option for lateral monotonic and cyclic loading applications.

Jan 1, 2011

By Alain Pecker

The choice of a design concept for a bridge foundation is guided by various factors; several of these factors are indeed of technical origin, like the environmental conditions in a broad sense, but others non technical factors may also have a profound impact on the final design concept. The foundations solutions adopted for the Rion Antirion bridge are described and an attempt is made to pinpoint the major factors that have guided the final choices. The Rion Antirion bridge is exemplar in that respect: the foundation concept combines the simplicity of capacity design, the conceptual facility of construction and enhances the foundation safety. The design of these foundations was a very challenging task which required full cooperation and close interaction with all the parties involved: concessionaire, contractor, designers and design checker.

Jan 1, 2013

By Jeffrey R. Hill

This paper discusses the use of micropiles for the rehabilitation of the following two structures: the Milwaukee Auditorium Theatre, in Milwaukee, Wisconsin, and the Cupples Ballpark Lofts, in St. Louis, Missouri. The paper focuses on the similarities and differences of the remediation techniques used for each structure. The discussion highlights the method of attaching the micropiles to each respective structure. Generally the paper discusses the micropile installation at each project with supporting photos, figures and data. Load testing at each project is also discussed, including the comparison of load test results for each project. The paper will focus on the load testing program at the Milwaukee Auditorium Theatre where high capacity micropiles were designed and tested as friction piles founded in stiff clays and end bearing micropiles in dolomitic limestone. The results of the test were used to determine if the micropiles on the project would be installed as end bearing or friction bearing elements. Strain gauges were used in addition to conventional deflection vs. load data for the Milwaukee Auditorium Theatre project. Other aspects of the paper will include the differences in design methodology for end bearing micropiles in massive dolomitic limestone vs. design in softer, weathered limestone.

Jan 1, 2008

By Clifford J. Wren

A geotechnical foundation solution was required to halt and prevent further structural distress suffered by a residential four storey apartment building in Hamilton, Scotland. Residents of the ten year old building started to notice cracking and signs of distress approximately one year after moving into the property. A detailed intrusive inspection of the structure revealed that the building was moving and had suffered significant settlement and structural distress at the shared party wall between it and an adjoining building. Roger Bullivant Limited (RBL) was appointed Principal Contractor to carry out an agreed remedial works contract which included a complete structural ?strip-out? of the ground floor, underpinning, contiguous bored pile retaining wall and reinstatement. The paper describes how a proprietary pile and needle beam underpinning system was used to prevent further differential movement and provide a new secure foundation for the residential building. The case study illustrates how a flexible problem solving approach can be applied to a difficult and sensitive geotechnical project.

Jan 1, 2008

By Franz-Werner Gerressen

In the changing construction environment clients are searching for new technology to complete their projects in shorter times. Manufacturers are therefore developing solutions to speed up established construction methods. The significant progress in recent years with the development of increasingly powerful drilling rigs is providing piling companies increase options for the execution of specialist foundation projects. The double rotary drilling methods are primarily used for the construction of pile walls as support for deep excavations. Typically these retaining walls are designed and installed as cased piles using the established Kelly drilling mode. However, more recently it is more popular to undertake these projects with the Cased Continuous Flight Auger (CCFA) system. This paper provides an overview of drilling with double rotary methods, in particular the monitoring during installation.

Jan 1, 2009

By Sebastian Fischer, Rolf Katzenbach, Steffen Leppla

"The risk management in the case of liquefaction is one of the most serious and also difficult issues in geotechnical engineering because failure caused by liquefaction is always a sudden failure without ahead indication. For that reason ground improvement technologies for the prevention of liquefaction are necessary. The paper explains the responsible and effective risk management. Methods for the risk management and stabilizing the soil sustainably are described in detail.1. INTRODUCTIONDue to population growing more and more settlement area is needed, which is often including improper regions (e.g. mountain and coast regions) with raised risk of various kinds of disasters. But also in densely populated areas the risk of disasters like landslides can occur. One reason for the raising of risk in densely populated regions can be the opencast mining for raw material production. An essential element of the opencast mining is the loose deposition of the removed overburden, the so-called “overburden dump”. When an opencast mining is running out of the raw material, an opencast hollow remains in landscape. The slope areas of these hollows mostly consist of loose bedded material of the overburden dump. Due to the end of groundwater conservation these loose bedded slope areas are flooded. In consequence the slopes are in extreme danger of becoming liquefied. The result of a liquefaction in these slopes will unavoidably be a slope slide. Such a slope slide can extend up to several hundred meters into the landscape and can move several million cubic meters of material. An upsetting example for such a landslide is the slope failure in the German city of Nachterstedt on July, 18th 2009, which made necessitate remedial measures and also prevention works for the further utilisation of the region. The phenomena of liquefaction is not limited of slopes in series of opencast mining. Especially in regions with a highly appearance of earthquakes the phenomena of liquefaction is well known.2. RISK MANAGEMENTAn essential part for the stability assessment of slope systems is the investigation of sensitivity against liquefaction. In the case of given sensitivity against liquefaction there is no calculation method according to soil mechanics to determine the factor of safety against slope failure. Just for the case that sensitivity against liquefaction is not met, a comparison of the load (effect) E and the resistance R which is the traditional verification of stability against slope failure, can be calculated (Figure 1)."

Jan 1, 2015

By Alan Christopherson

Nearshore construction projects often require installation of steel piles and specific methodologies of installing piles may adversely affect nearby species of concern. Water is an uncompressible medium which allows for easy transmission of energy through the water column. Energy transmission through water depends on the following factors for pile driving: 1) direct contact of the pile and the water; 2) the depth of the water column; 3) the size of the pile; 4) type of hammer; and 5) the energy of the hammer. Seasonal restrictions are usually the best practicable alternative for reducing habitat impacts when pile driving activities may adversely affect the species of concern. When seasonal restrictions are not practical other options need to be evaluated, including mitigation and noise attenuation devices. The broad array of mitigation options will not be discussed as part of this presentation but instead will focus on noise attenuation technologies. Dewatered cofferdams can be effective noise attenuators as they eliminate direct contact of the pile with water while driving. Also, introduction of a compressible medium, like air, near the energy source can provide sound energy attenuation. An unconfined bubble curtain is relatively inexpensive but is not effective in tidal marine projects or rivers and may have unacceptable secondary effects. Secondary effects must be evaluated as these can increase exponentially for larger projects. Secondary effects to the environment include air quality degradation from air compressor use, transportation costs for fuel and equipment, and the potential for injecting oily compressed air into the water column. The confined bubble curtain works well in nearly all environments. It usually is more expensive initially, relative to an unconfined air curtain, but there is less potential for harmful secondary effects. Generally, seasonal restrictions will be adequate to protect species of concern. However, there are conditions in which mitigation or one of the sound attenuation options should be utilized. Site specific factors, including the amount of energy being imparted into the environment, sensitivity of the species of concern, current, accessibility, length of time needed to complete the project, and the cost of the sound attenuation, should be factored into the permit evaluation.

Jan 1, 2013

By J. G. La Fonta

The rapid development of real-time monitoring technology for the construction of large underground structures in urban areas can be attributed to: the zero-risk objective, the need for transparency between all parties involved and the control of real cost within the budget. Real-time monitoring can be an integral part of the construction contract (for example when compensation grouting is required) or independent, in particular when measurements of existing structures and buildings bordering the project are to be taken before construction starts. Three examples of extensive field instrumentation schemes are described: a large road tunnel in the Moscow suburbs, a new metro line in Amsterdam and major redevelopment works at a busy Central London rail interchange.

Jan 1, 2006

By E. W. Raabe

The paper discusses the increasing role of specialist grouting techniques to form water seals or cut-offs for deep basement construction. Raabe and Toth discuss the various grouting methods available for sealing applications and then concentrate on the use of Soilcrete Jet Grouting, a system particularly well suited to ground water control. The Soilcrete processes, suitable soil types and quality control methods are fully described, particularly with regard to the formation of cut-off walls and sealing slabs to prevent the progress of ground water or leachates. The authors have included case histories detailing their experience on designing and installing Soilcrete seals for various projects in West Germany. These include an underground rail project in Dortmund and a discharge structure for the Alz Canal at Burghausen.

Jan 1, 1989