Deep Excavations for the Manufacturers Life Centre, Toronto

1972 ◽  
Vol 9 (2) ◽  
pp. 137-144
Author(s):  
G. D. Prasad ◽  
C.F. Freeman ◽  
D. Klajnerman
Keyword(s):  
Field Tests ◽  
Full Scale ◽  
Triaxial Tests ◽  
Design Parameters ◽  
Loading Test ◽  
Deep Excavations ◽  
Design Procedures ◽  
Load Tests ◽  
Geotechnical Design ◽  
Soldier Pile

Geotechnical considerations associated with deep excavations for the Manufacturers Life Centre in Toronto are discussed. The depth to shale bedrock and the necessity to obtain maximum access to the foundation grade resulted in selecting the use of tie backs into the overburden with or without rakers for supporting the soldier pile lagging system. Full scale load tests were carried out to prove the recommended geotechnical design parameters for the shoring system. Adhesion values obtained from full scale field tests on tie backs agreed closely with the shear strength obtained from laboratory quick triaxial tests. However a full scale loading test on an inclined raker footing gave a higher bearing value compared with conventional design procedures.

Full-scale field tests on directly embedded steel pole foundations

2000 ◽  
Vol 37 (2) ◽  
pp. 414-437 ◽  
Author(s):  
Asim Haldar ◽  
VSN Prasad Yenumula ◽  
T R Chari
Keyword(s):  
Field Tests ◽  
Ground Level ◽  
Full Scale ◽  
Design Parameters ◽  
Embedment Depth ◽  
Ultimate Capacity ◽  
Backfill Material ◽  
Different Types ◽  
Full Scale Tests ◽  
Laterally Loaded

The results of eight full-scale tests on directly embedded steel pole foundations are presented. Fully instrumented poles were tested to measure the various design parameters. Different types of backfills such as sand, in situ gravelly sand, crushed stone, and flowable material were used. Various parameters were measured, including applied moment, ground line deflection-rotation, rotation of the pole below the ground level, soil pressures, and bending moments in the poles. The behaviour of these foundations was explained through ultimate capacity and moment-rotation characteristics. Based on these test results, it was found that the capacity of the directly embedded pole foundation depends primarily on the compaction levels of backfill and the embedment length of the pole. Flowable backfill material, which does not require any compaction, was found to be most effective and promising. Even when the backfill was loose, the lateral capacity significantly increased by the addition of a baseplate or by installing the pole with an additional embedment depth. Various theories developed for laterally loaded rigid piles were used to predict the moment-rotation behaviour and the ultimate capacity of the directly embedded pole foundation with different types of backfill material. Results from the analytical investigations were compared with those obtained from the full-scale load tests. Comparisons show that the ultimate capacities predicted by the models ranged from 0.30 to 2.20 times the measured capacities.Key words: backfill, compaction, full-scale tests, laterally loaded rigid piles, transmission steel poles, ultimate moment.

scholarly journals Experimental and numerical analysis of foundation pilings partially embedded in rock

2013 ◽  
Vol 66 (4) ◽  
pp. 439-446
Author(s):  
Jean Rodrigo Garcia ◽  
Paulo José Rocha de Albuquerque ◽  
Rodrigo Álvares de Araújo Melo
Keyword(s):  
Load Transfer ◽  
Three Dimensional ◽  
Field Tests ◽  
Soil Surface ◽  
Residual Soil ◽  
Geotechnical Parameters ◽  
Weathered Rock ◽  
Load Tests ◽  
Geotechnical Design ◽  
Transfer Method

The behaviours of four foundation pilings (ϕ=0.41 m) constructed in Foz do Iguaçu, Paraná (PR), Brazil and subjected to slow loading tests were analysed. The results were compared with results from three-dimensional numerical modelling using the finite element method, which facilitates simulation of the elasto-plastic behaviour of soil. The local subsoil comprises varied stratigraphies; it is composed of a residual soil surface layer followed by weathered rock and bedrock, which are a few meters deep. The massif geotechnical parameters were determined through correlations obtained from field tests, whereby the values for cohesion, angle of friction, modulus of deformability and uniaxial compressive strength in the different subsoil layers were estimated. The load tests were interrupted at 3000 kN and displaced by less than 5 mm in the working load (1500 kN). The pilings were subjected to lateral friction work with an average stress of approximately 70 kPa for the surface portion (residual soil) and greater than 150 kPa for the weathered rock portions. The estimated geotechnical parameters provided values that were an exact match with the numerical analyses. Thus, given the analyses and load transfer method, the piling lengths can be reduced, which will facilitate the optimisation of the geotechnical design.

scholarly journals The Case of the New Tagus River Leziria Bridge

2016 ◽  
Author(s):  
Pedro Sêco e Pinto ◽  
Ricardo Oliveira ◽  
Alexandre Portugal
Keyword(s):  
Field Tests ◽  
Triaxial Tests ◽  
Direct Shear Tests ◽  
The North ◽  
Tagus River ◽  
Load Tests ◽  
Pile Load Tests ◽  
Seismic Tests ◽  
Penetration Tests ◽  
Main Bridge

A brief description of the New Tagus River Leziria Bridge composed by 1695 m North Viaduct, by 970 m Main Bridge and by South Viaduct with a length of 9200 m is presented. The observed thickness of the foundation alluvia material varies between 35 m and 55 m with a maximum value of 62 m. Hundred eighteen boreholes were performed with a depth between 21 m and 71 m and eight boreholes were performed from a maritime platform. Standard penetration tests (SPT) were carried out in all boreholes 1.5 m apart. In addition CPTu tests, seismic cone tests, crosshole and downhole tests were performed. In three boreholes continuous undisturbed sampling with a triple sampler Geogor S was performed. Related with static laboratory tests namely identification tests, triaxial tests, direct shear tests and oedometer tests were performed. In addition for the dynamic characterization reasonant columns tests and torsional cyclic tests were performed. One of the most important considerations for the designers is the risk of earthquakes since Lisbon was wiped out by an 8.5 Ritcher magnitude earthquake in 1755. The seismic studies related to the design spectra were performed. The liquefaction potential evaluation was performed only by field tests taking into account the disturbance that occurs during sampling of sandy materials. In this analysis attention was drawn for SPT and CPT tests as seismic tests have only been used when soil contains gravel particles. The shear stress values were computed from a total stresses model, that gave results on the conservative side using the code “SHAKE 2000”. For the North and South Viaducts 1.5 m diameter piles were used and for the Main Bridge 2.2 m diameter piles were used. For the construction of the piles metallic casings were driven by a vibrofonceur or a hydraulic hammer and the piles length varies between 20 m to 56 m. Static pile load tests (both vertical and horizontal tests) were carried out on trial piles. In addition pile dynamic tests were performed. The construction aspects related with piles and bridge construction are addressed. To assess the integrity of the piles reception tests by sonic diagraphies (crosshole tests) were performed. Some problems that have occurred during piles construction in the Main Bridge, due to the gravel and cobbles dimensions, are described. The bridge was monitored with the purposes of: (i) Validation of design criteria and calibration of mental model; (ii) Analysis of bridge behavior during his life; and (iii) Corrective measures for the rehabilitation of the structure.

scholarly journals Analysis of the bearing capacity of unbound granular mixtures with rubber particles from scrap tyres when used as sub-ballast

2016 ◽  
Vol 66 (324) ◽  
pp. 105 ◽  
Author(s):  
C. Hidalgo-Signes ◽  
P. Martínez-Fernández ◽  
J. Garzón-Roca ◽  
R. Insa-Franco
Keyword(s):  
Bearing Capacity ◽  
Field Tests ◽  
Triaxial Tests ◽  
Rubber Content ◽  
Cyclic Triaxial ◽  
Cyclic Triaxial Tests ◽  
Granular Mixtures ◽  
Rubber Particles ◽  
Load Tests ◽  
Plastic Creep

Scrap tyres are a problematic waste material. As a method for recycling large quantities of rubber from scrap tyres, this paper analyses the use of unbound granular mixtures with varying percentages of rubber particles as sub-ballast in railway lines. Bearing capacity for such mixtures is studied in laboratory and field tests using static and dynamic plate load tests, as well as cyclic triaxial tests. It is found that adding rubber increases permanent and resilient strain and that none of the mixtures suffer plastic creep after 2.5 million cycles. Considering the usual bearing capacity requirements, the optimum rubber content is 2.5% (by weight). This percentage increases resistance to degradation while ensuring sufficient bearing capacity.

Design of shallow rock-anchored foundations

1982 ◽  
Vol 19 (4) ◽  
pp. 463-471
Author(s):  
Nabil F. Ismael
Keyword(s):  
Transmission Lines ◽  
Design Parameters ◽  
Test Results ◽  
Design Procedures ◽  
Uplift Pressure ◽  
Rock Types ◽  
Rock Formations ◽  
Load Tests ◽  
Rock Anchors ◽  
Important Design

Full-scale uplift and lateral load tests were carried out on rock anchors and rock-anchored foundations at several sites in the Province of Ontario. Various rock types were tested, ranging from soft shale to sound limestone. The results are presented; they were analyzed and important design parameters were determined for different rock formations. Based on test results, simplified design procedures were developed for the convenience of the design engineer. Keywords: Anchors, rock, transmission lines, foundations, tests, loads, design criteria, uplift pressure.

Effect of guy cable constraint on structural damping of open lattice antenna towers

1980 ◽  
Vol 7 (4) ◽  
pp. 614-620
Author(s):  
J. S. Kennedy ◽  
D. J. Wilson ◽  
P. F. Adams ◽  
M. Perlynn
Keyword(s):  
Natural Frequencies ◽  
Damping Ratio ◽  
Field Tests ◽  
Full Scale ◽  
Structural Damping ◽  
Scale Field ◽  
Modes Of Vibration

This paper presents the results of full-scale field tests on two steel guyed latticed towers. The towers were approximately 83 m in height, were guyed at three levels, and were of bolted angle construction. The observed results consist of the natural frequencies of the first two modes of vibration as well as the damping ratio for the first mode. The observed results are compared with analytical predictions and observations made concerning the contributions of structural and cable action to the damping ratio.

THE RULE OF COMBINING A PRIORI AND EXPERIMENTAL INFORMATION IN THE TASKS OF MANAGING TESTS OF COMPLEX TECHNICAL PRODUCTS ACCORDING TO THE BERNOULLI SCHEME

2020 ◽  
pp. 3-13
Author(s):  
Yu. I. Buryak ◽  
A. A. Skrynnikov
Keyword(s):  
Field Experiments ◽  
A Priori ◽  
Field Tests ◽  
Experimental Information ◽  
Full Scale ◽  
Testing Complex ◽  
Series Of Experiments ◽  
Full Scale Tests ◽  
Technical Products

The article is devoted to the substantiation of the procedure for testing complex technical systems to assess the probability of performing the task, taking into account a priori data obtained from the results of modeling, field tests of components and prototypes, operation of analogues, etc. The conditions for the formation of a combined sample consisting of field experiments and experiments counted on the results of modeling are justified. Data uniformity is checked using the Student's criterion. The minimum volume of full-scale tests is determined by the requirement of equality of the amount of Fischer information about the estimated parameter obtained during full-scale tests and at the expense of a priori data A strategy for conducting field experiments is proposed, in which the required quality of evaluating the probability of completing the task is achieved with the minimum possible number of field experiments. At the first stage, a series of experiments with a volume equal to half of the required sample size is performed. At the second stage, the experiments are conducted sequentially with an assessment after each experiment of the requirements for the amount of information about the evaluated parameter and for the uniformity of data. Experiments are terminated when the specified requirements are met, and then a combined sample is formed, which is used to evaluate the probability of the system performing the task. A model example is considered. The estimation of the gain in the number of experiments performed at different probability values was carried out.

Estimation of Seismic Energy Dissipation for Steel Slit Shear Walls Considering Out-of-Plane Buckling

2021 ◽  
Author(s):  
Yiming Ma ◽  
Liusheng He ◽  
Ming Li
Keyword(s):  
Energy Dissipation ◽  
Shear Walls ◽  
Seismic Energy ◽  
Thickness Ratio ◽  
Design Parameters ◽  
Test Results ◽  
Loading Test ◽  
Aspect Ratios ◽  
Out Of Plane ◽  
Energy Dissipation Capacity

Steel slit shear walls (SSSWs), made by cutting slits in steel plates, are increasingly adopted in seismic design of buildings for energy dissipation. This paper estimates the seismic energy dissipation capacity of SSSWs considering out-of-plane buckling. In the experimental study, three SSSW specimens were designed with different width-thickness ratios and aspect ratios and tested under quasi-static cyclic loading. Test results showed that the width-thickness ratio of the links dominated the occurrence of out-of-plane buckling, which produced pinching in the hysteresis and thus reduced the energy dissipation capacity. Out-of-plane buckling occurred earlier for the links with a larger width-thickness ratio, and vice versa. Refined finite element model was built for the SSSW specimens, and validated by the test results. The concept of average pinching parameter was proposed to quantify the degree of pinching in the hysteresis. Through the parametric analysis, an equation was derived to estimate the average pinching parameter of the SSSWs with different design parameters. A new method for estimating the energy dissipation of the SSSWs considering out-of-plane buckling was proposed, by which the predicted energy dissipation agreed well with the test results.

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