Geotechnical Engineering Commons^™

Case Histories And Vibratory Characteristics Of Vibro-Driven Piles, Hideo Tsuboi, Tamotsu Matsui

International Conference on Case Histories in Geotechnical Engineering

The vibratory characteristics of vibro-driven piles into the ground have not so far been discussed systematically in detail. This paper concerns the results of monitoring vibro-driven piles in various types of ground. In order to assess the monitoring of vibration performance, time-series monitoring data on the reaction force at the pile tip and the vibratory acceleration of the pile top are analyzed in relation with the soil profiles of four monitoring sites. As the result, it has been elucidated that the pile tip reaction force and vibratory acceleration are systematically presented by the dynamic force and the mass weight of …

Ground Vibrations Isolation By Pc Wall-Piles, Kiyoshi Hayakawa, Yukihiko Kani, Noriyuki Matsubara, Tamotsu Matsui, Richard Woods

International Conference on Case Histories in Geotechnical Engineering

This paper presents the results of a series of experiments conducted on a PC wall-piles barrier. That barrier was built alongside a road passing through some sensitive sites, to assess its effectiveness in isolating vibration caused by running trains and dropping a weight. Then the effectiveness of PC wall-piles for controlling ground vibrations is discussed. Field measurements were performed for 5 cases having different types of PC wall-piles. The simultaneous measurement of vibration was performed at several selected points on the ground. Finally, a method for estimation of vibration reduction by PC wall-piles was developed, being based on wave penetration …

On Prediction Of Dynamic Response Of Horizontal Vibrations, Shamsher Prakash, Damodaran Nampoothiri

International Conference on Case Histories in Geotechnical Engineering

The coupled horizontal sliding and rocking response of block foundations, subjected to a ham1onic horizontal force or a moment or both has been determined. Computed response have been compared with that from an experimental study carried out by Kovak and Beredugo (1971, 1972). The computed values do not match the measured response. The computed stiffness and damping were modified to match the measured response. More analysis of experimental data is needed to determine necessary correction factors.

Radiation Damping Of Soil - Foundations Interaction Systems, Yang Xianjian, Jiang Bei

International Conference on Case Histories in Geotechnical Engineering

Based on the theory of wave scatter and the velocity, the wave radiation which is caused in soil of dynamic foundation and the range of the affected depth are presented in this paper. It is pointed out that the mass ratio of foundation and the location of the foundation in the layered soil, and its propagation velocity in the affected depth, are the major factors affecting radial damping of soil-foundation system on the half space.

Abnormal Wall Movements Of A Steel Silo Caused By Paddy Rice Storage, Minh Phong Luong

International Conference on Case Histories in Geotechnical Engineering

The particular rheological behaviour of paddy rice and husked rice, that is readily determined in laboratory using the conventional triaxial apparatus, provided a realistic interpretation of an unusual case history occurred on a large rice storage steel silo Subsequently 11 suggested minor modifications, but quite sufficient to ensure the facility availability at different stages of rice storage.

Behavior Of Braced Deep Excavation In Soft Soils, Changjie Xu, Yuanqiang Cai, Shiming Wu

International Conference on Case Histories in Geotechnical Engineering

A successful case study of braced deep excavation in Hangzhou, 1994, is presented in this paper. A stiff braced retaining structure was adopted through theoretical analysis, the bottom soil of the pit was strengthened by cement mixed grouting to increase the stability of the retaining structure. The excavation was completed smoothly in short period of time, displacements surrounded the pit and stresses in braces were measured during the whole procedure of excavation and the measured results agreed well with the prediction by FEM. Some conclusions drawn from this successful case may be instructional to other similar engineerings.

Behavior Of Double-Row Pile Retaining Structure For Deep Excavation In Soft Clay, Yuanqiang Cai, Shiming Wu, Yunmin Chen, Changjie Xu

International Conference on Case Histories in Geotechnical Engineering

An excavation of 10.5m deep and 110m x 70m in plane with double-row pile retaining structure in soft clay has been completed, which is of severa1 advantages, such as elimination of lateral deflection and ground surface settlement, low cost and short duration of excavation. This paper presents tile design considerations, procedure of construction and excavation, behavior of this type of retaining structure. The FEM analysis has been carried for prediction of lateral deflection and stress, the results from FEM method conformed well with field measurement, some conclusions drawn from the design and construction Mil be valuable for future construction in …

Large Retaining Structures Reinforced By Geosynthetics: French Case Histories, Jean-Claude Blivet, Jean-Pierre Gourc

International Conference on Case Histories in Geotechnical Engineering

French experience in earth embankments reinforced by geosynthetics dates back more than 25 years. This technique was developed on the basis of reference structures fitted with instruments to monitor their behaviour. Three of the largest structures built have been chosen in this paper as they are typical of the different construction technologies used in France.

Numerical Modeling Of A Crib-Wall Failure, Wolfgang H. Roth, Alexander Delnik

International Conference on Case Histories in Geotechnical Engineering

The 2-D finite difference program FLAC was utilized to investigate the probable cause of failure of a crib wall at Hebrew Union College in Los Angeles. Shortly after reaching its final height of 45 feet, cracking/crushing of the precast-concrete elements had been observed, and the crib wall was lowered to 35 feet. In spite of this design change, however, a portion of the wall later collapsed following prolonged rainfalls in March of 1992. In analyzing the construction stages and subsequent wall failure, a simple Mohr-Coulomb constitutive model was coupled with seepage analysis to simulate the effect of rainwater infiltration. Two …

Pier Failure Of Bridge And Geotechnical Investigation − A Case Study, J. K. Jain, A. K. Saxena, Sanjay Kumar Shrivastava

International Conference on Case Histories in Geotechnical Engineering

In this paper a case of foundation failure, due to which the complete bridge structure has collapsed, is considered. The bridge is situated in Km. 26/6 on Langi Durg Road. It was constructed in the year 1980-81. This bridge has two solid slab spans of 15.25 meters each. The substructure is of solid coarse rubble stone masonry. The base dimensions of pier foundation are 3780 mm. in traffic direction and 10080 mm. in current direction at R.L. 94.00m. The pier foundation is resting on bouldary strata. During the floods in the year 1995 the pier constructed in mid-stream failed. This …

Shoring Analysis, Design And Construction At The Seattle Symphony's Benaroya Hall, Carole L.B. Mitchell, Monique A. Nykamp

International Conference on Case Histories in Geotechnical Engineering

Complex loading and geometry conditions controlled the design of the shoring wall system at Benaroya Hall, the new home of the Seattle Symphony. A combined system, including three soldier pile and tieback walls and one soil nail wall, was used to shore an excavation that ranged from 15 to 50 feet deep. A 25-foot-wide block of soil remained between the soil nail wall face and an existing, underground bus station. Prior to designing the soil nail wall, a finite difference analysis was performed to determine potential movements of the station due to the excavation. The deflection estimates from the finite …

Soil Nailing: The Modot Experience, Kevin W. Mclain

International Conference on Case Histories in Geotechnical Engineering

Soil nailing is a construction technique that is used to strengthen existing ground by installing grouted steel bars into the ground at closely spaced intervals. This increases the shear strength of the in-situ soil so that successive excavation lifts from top down can be made. The Missouri Department of Transportation (MoDOT) has overseen the construction of two temporary soil nail walls in the St. Louis metro area and one permanent wall in the Kansas City metro area. All three projects involved roadway widening under existing overpasses, which required the removal of the soil berm and construction of a soil nail …

Comparison Of Two Excavation Support Systems In Clay: Central Artery Tunnel, Boston, Massachusetts, Usa, Siamac Vaghar, Dan J. Bobrow

International Conference on Case Histories in Geotechnical Engineering

Two types of excavation support system were used on the southern approach of the Ted Williams Tunnel; part of Boston’s Central Artery/Tunnel Project. Construction commenced in 1992 and was completed in 1995.

The cut and cover tunnel was constructed to accommodate a four-lane highway, and associated structures. The excavation was mainly in soft marine clays, known locally as the Boston Blue Clay. The main excavation support system consisted of tied-back interlocking steel sheeting. The proximity of large commercial buildings to the excavation necessitated a stiffer support system to reduce the magnitude of ground deformation at the building locations. A 3-feet …

A Computer Aided Rock Mass Classification For Rock Slopes, Hong Li, Gang Li

International Conference on Case Histories in Geotechnical Engineering

This paper proposes a new microcomputer aided geomechanical classification for rock slopes. This classification for rock slopes is established based on well known established rock mass classification such as the CSIR classification, the Q classification, SRM classification and the Chinese Engineering Rock mass Classification (CERC) and the concept of “preferred planes”. In order to obtain a useful result by taking account to the complicated geological conditions and the multiple goals decision, a computer aided geomechanical classification for rock slopes (CSRSS) has been built based on the expert system design skills. The case studies showed that the classification system works well. …

Erosion And Repair Of Unlined Spillway Chute Excavated In Rock, David Mathews, Vlad G. Perlea, Francke C. Walberg, Douglas R. Anderson

International Conference on Case Histories in Geotechnical Engineering

Discharges up to 60,000 cfs that lasted 21 days caused extensive erosion of the unlined spillway chute excavated in alternating layers of limestone and shale. An empirical model allowed to evaluate the extent of erosion anticipated for future events. Parametric calculations showed that relatively low discharges a long period of time are critical for the induced damage. It was determined that the spillway can safely pass the design discharge if weathering of rock exposed by erosion is prevented. Accordingly, the interim repair was designed to protect the rock units, especially the critical limestone layers, from weathering. Although it is expected …

Remedial Works In Tile Ljubelj Tunnel, Borut Petkovšek, Lojze Bevc

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

Stability And Permeability Of Fluid Retention Berms Constructed From Highly Weathered Bedrock, Paul Michael Santi

International Conference on Case Histories in Geotechnical Engineering

A geotechnical evaluation was conducted of thirteen emergency impoundment basins constructed to retain fluids from catastrophic tank failure at a petroleum facility. The berms creating the impoundments were constructed on bedrock, weathered bedrock, slope wash, and lightly compacted fill derived from weathered bedrock.

Site materials ranged from fractured rock, to clayey gravel, to gravelly sand. Consequently, standard geotechnical tests for strength and permeability were difficult to perform, and test results were not often representative of the entire range of properties at each basin. Therefore, a systematic method of testing or estimating strength and permeability ranges was established. In order of …

Tunnex: An Experiment System For Tunneling Through Rock, Massoud Palassi, John A. Franklin

International Conference on Case Histories in Geotechnical Engineering

The expert system Tunnex provides an interactive consultation on the excavation of tunnels through rock. As a first step it examines the interdependence between rock quality, unsupported span and stand time of the excavation (the “O-S-T” relationship) to determine the likely overall behavior of tunnels of different diameters, the time available for installation of supports, and the optimum choice of tunnel diameter, single or twin tunnels when such choice is available. Stand-time considerations also guide decisions on the deed or otherwise for a pilot heading or staged excavation. Tunnex guides the user in forecasting primary and secondary support requirements and …

Tunneling In Squeezing Ground, J. C. Chern, C. W. Yu, H. C. Kao

International Conference on Case Histories in Geotechnical Engineering

A criterion for identifying the squeezing potential of tunnel is proposed. Tunneling conditions, classified as slightly or non-squeezing, moderately squeezing and highly squeezing, were identified by relating the strength-stress (σ_cm/P_o ) ratio to the development of plastic zone extent and the amount of tunnel closure. Actual case histories of tunneling in Taiwan show that this criterion predicts the tunnel performance quite well. This enables the identification of tunneling conditions expected which require special considerations in support design and excavation-support procedures.

A Case History Of Ground Treatment For A Power Station In China, Xiaohong Bai, Jungang Jia, Qiuxue Yang

International Conference on Case Histories in Geotechnical Engineering

This paper presents a case history of ground treatment for a large power station - Zhang Ze Power Station, which locates in the south-east region in Shanxi, P. R. China. In the second phase of this project, a comprehensive treatment program including pile foundation, dynamic consolidation, and natural foundation has been used successfully according to significance of structure, conditions of loading, characters of technology, and so on. After 6 years working, the Station operates normally, and settlements of structures distribute well, proving the program is reasonable, workable, and economic. It is suggested that the choice of foundation treatment in a …

Composite Ground Modification System: Vibroreplacement And Dynamic Compaction, Salt Lake County Detention Center, Utah, Roberto A. López, Mathew J. Francis, Kyle M. Rollins, Scott W. Davis, Zoran Batchko

International Conference on Case Histories in Geotechnical Engineering

The site for a new Adult Detention Center currently under construction in Salt Lake City, Utah, is underlain by loose sands and soft clayey lake deposits. Due to bearing capacity, static settlement, and liquefaction concerns, a hybrid ground improvement program consisting of both dynamic compaction and vibroreplacement was implemented. Stone columns were concentrated under spread and wall footings; dynamic compaction was performed over the whole site. A comprehensive quality assurance/ quality control program was executed, with a significant number of cone penetration tests, standard penetration tests, 10 plate load tests, and deceleration readings taken with an accelerometer mounted on the …

Construction Of Inchon International Airport, Eun Chul Shin, Bang-Woong Shin

International Conference on Case Histories in Geotechnical Engineering

To face with the increasing the air transportation in Korea, the construction of Inchon International Airport is underway in the bay of Inchon on the reclaimed land. The construction project has begun since the end of 1992, and will be completed by the end of year 2000. This paper presents the general plan of project, site development, soil improvement work, transportation system, and construction budget and fund.

Ground Improvement At The Queensway Bay Downtown Harbor, Long Beach, California, Suji Somasundaram, Gamini Weeratunga, Kris Khilnani

International Conference on Case Histories in Geotechnical Engineering

Vibro-replacement with stone columns was selected as the optimum ground improvement solution to mitigate liquefaction potential, provide seismic stability, and provide adequate structure foundation support for a proposed harbor/marina development at an oceanfront site. The site is underlain by up to 27 meters of soft/loose hydraulic fills and seafloor sediments. An 18-meter wide ground improvement zone straddling the proposed 600-meter long bulkhead wall alignment was designed to create a non-liquefiable barrier that would prevent flow failures towards the lagoon, limit seismically induced deformations to acceptable levels, and allow the wall to be supported on shallow footings. The construction of a …

Grouting Evaluation Program Of The Best Methods For Use Of Microfine And Portland Cements During Treatment Of The Rock Foundation At The Portugues Dam, John Conway, Tom Novak

International Conference on Case Histories in Geotechnical Engineering

The U.S. Army Corps of Engineers, Jacksonville District, recently completed a grouting program in Ponce, Puerto Rico, for the Portugués Dam. The program compared microfine cement to Portland cement and helped determine the most efficient and economical method to construct the grout curtain. The foundation rock consists of volcanic sediments. A diorite stock upstream of the site altered the volcanic sediments by low grade metamorphism to metasediments, cause numerous radiating dikes and shears and a highly fractured foundation. Most of the fractures are relatively tight or healed. A bore hole video camera recorded in-situ fracture frequency, orientation and aperture thickness …

Guidelines For Sealing Geotechnical Exploratory Holes, Cameran Mirza, Robert K. Barrett

International Conference on Case Histories in Geotechnical Engineering

A three year research project was sponsored by the Transportation Research Board (TRB) in 1991 to determine the best materials and methods for sealing small diameter geotechnical exploratory holes. A key requirement of the research project was to verity the effectiveness of the in-place seals. Seal verification studies were conducted at two sites, one in the USA and one in Canada. Seals consisting of various bentonite products and Portland cement were installed and allowed to age. Periodic in situ hydraulic conductivity tests were performed at the Canadian site. Seal exhumation studies were conducted at the USA site. Upon completion of …

Investigation Of Landslides Affecting A Romanian Railway, Ion Stanculescu, Florian Braniste, Ion Borsaru

International Conference on Case Histories in Geotechnical Engineering

The study of the landslides that occurred on the hillside between Covurlui plateau and Brates Lake is presented, together with geotechnical investigations performed in order to establish the trigger mechanism of the registered cyclical instability phenomena. Laboratory test results showing the peculiarities of the clay strata, mineralogical, physical, and mechanical properties are discussed, and stability analysis results are commented, in order to substantiate the proposed consolidation measures.

Lime Slurry Injection, Lime Piles And Stone Columns For Improvement Of Soft Soils − Field Trials, A. K. Gupta, Satish Kumar, D. S. Tolia

International Conference on Case Histories in Geotechnical Engineering

Scarcity of good land available for construction has resulted in development of a number of techniques for improvement of ground. If properly treated, most soils can be made into useful construction materials. Two case histories arc presented utilizing two different kinds of ground improvement techniques. Field scale trials are conducted to reinforce deep deposit of soft marine clay with stone columns and a road embankment made with black cotton soil modified with lime columns and pressure injection of lime slurry. Both techniques resulted in significant improvement in strength and settlement characteristics.

Observations On Landslide Incidences In Himalayas In Kashmir Area, A. K. Gupta, Jai Bhagwan, B. C. Joshi

International Conference on Case Histories in Geotechnical Engineering

The Himalayas have been found to experience the highest frequency of landslide incidences, thereby, causing loss of life and property. The rocks of Himalaya are repeatedly deformed and are affected by the periodic reactivation of deepseated faults. The experiences in the area of landslide investigations reveal that these lineaments are characterised by the frequent occurrence of landslides. Recently, studies have been carried out on a number of landslides falling between Murree and Panjal thrust along the Karole-Kastigarh road in Ram ban area of Jammu & Kashmir. This paper is intended to present the salient features of some of these landslide …

Protection Of Kamorta Island From Coastal Erosion − A Case Study, Shri Pal

International Conference on Case Histories in Geotechnical Engineering

Soil erosion from steep banks of Kamorta Island due to rain and strong sea waves caused serious damages to slopes and threatened the safety of Helipad and Naval buildings on the Island. Two types of protective works were adopted in the area to stabilize the slopes and protect them from erosion. The adequacy of design, construction, performance and economy of these protective works are discussed in this paper. It is concluded that reinforced soil walls are more economical, easier in construction and more eco-friendly in remote islands as compared to conventional type of construction.

Red Onion Mountain Maximum Security Prison − A Case Study In Ground Improvement, Steven J. Winter, Victor Omelchenko

International Conference on Case Histories in Geotechnical Engineering

The Red Onion Mountain project involved the construction of a high security prison facility in a remote area of southwest Virginia. The site of the proposed construction was covered with a thick layer of uncontrolled mine spoil fill material containing a random matrix of soil and boulders. This material was unsuitable for the proposed construction in its existing condition. Charged with evaluating feasible and cost effective alternatives for site development and structural support, the project's geotechnical engineers devised a two-phase ground improvement plan designed to adequately improve the existing mine spoil fill. Full-time observation, documentation and testing during the site …