Prediction Of Embankment Settlement Research Articles

Prediction of embankment settlement on Swedish peat using the Soft Soil Creep model

Despite the prevalence of peat in northern areas of Europe and elsewhere, there are comparatively few case histories of carefully monitored embankments constructed directly on peat. In addition the...

Experimental evidence about misconception of Terzaghi's 1-D consolidation theory in terms of degree of consolidation

Terzaghi's 1-D consolidation theory is commonly used for prediction of embankment settlement in soft fine-grained soil. Application of this theory is not always effective due to the simplifications of assumed soil behavior under load. This paper examines relationship between the degrees of consolidation determined by pore water pressure measured at the base of the sample and one-dimensional strain. Theoretically, this relationship should be unique, however experimental relationships correlating the degrees of consolidation are found to be non-linear. The article presents the results of multistage consolidation tests with pore water pressure measurements, carried out on intact and reconstituted deep marine clay. Consolidation tests were conducted with uniform stress distribution and single-sided drainage conditions. It was observed that the relationship between degrees of consolidation for intact and reconstituted samples largely divergent from theoretical unique line.

A simplified method for prediction of embankment settlement in clays

The prediction of embankment settlement is a critically important issue for the serviceability of subgrade projects, especially the post-construction settlement. A number of methods have been proposed to predict embankment settlement; however, all of these methods are based on a parameter, i.e. the initial time point. The difference of the initial time point determined by different designers can definitely induce errors in prediction of embankment settlement. This paper proposed a concept named “potential settlement” and a simplified method based on the in situ data. The key parameter “b” in the proposed method was verified using theoretical method and field data. Finally, an example was used to demonstrate the advantages of the proposed method by comparing with other methods and the observation data.

Prediction of embankment settlements over marine clay using piezocone penetration tests

The paper discusses the use of piezocone penetration testing (CPTU) and evaluates four methods of interpretation for predicting the deformation constrained modulus (M) used to calculate the consolidation settlement of cohesive soil. CPTU tests were performed at eight embankment sites in the Lianyungang marine clay and high-quality samples for laboratory testing were collected close to the CPTU test locations. The constrained modulus (M) values predicted using the different interpretation methods were compared with the reference values determined from the laboratory consolidation tests. A new correlation was also developed to predict M from the net cone tip resistance (q t − σ vo ). The paper discusses a simple approach to the use of the CPTU method to estimate the settlements of expressway embankments

Estimating coefficient of consolidation from piezocone tests: Discussion

The authors are to be commended for their assembling of such comprehensive data in a manner that can be used by practitioners. The discussers, having recently completed a similar research project for the South African Roads Board, are acutely aware of the large amount of effort required to obtain such information. The primary objective of our project was to verify and calibrate the use of the piezocone for the prediction of embankment settlements on recent alluvial deposits. The secondary objective was to estimate coefficients of consolidation from piezocone data and hence calibrate the prediction of times for settlements. The data base for this comprised: ( i ) se t t lement records fo r up to 15 years fo r 12 embankments; ( i i ) original site investigation laboratory test results, including cone penetration test (CPT) data; and (iii) piezocone results carried out recently for the project ( u 2 filter location, see Fig. I). At some of the embankments, since the subsoil conditions were variable, more than one case history could be reconstructed, with the result that a total of 25 separate cases were available. It is hoped that the results of the project will be published shortly. In the meantime, however, the essential findings are given below. Using the conventional equation to derive m, from cone data, viz., 0.i 1 10 100 im ioooo tm, m l n

Prediction of embankment settlements by in-situ tests : Bergado, D T; Dario, P M; Sampaco, C L; Alfaro, M C Geotech Test JV14, N4, Dec 1991, P425–439

Prediction of embankment settlements by in-situ tests : Bergado, D T; Dario, P M; Sampaco, C L; Alfaro, M C Geotech Test JV14, N4, Dec 1991, P425–439

Closure to “Discussion on ‘Prediction of Embankment Settlements by In-Situ Tests,’ by M Gambin” by D. T. Bergado, P. M. Daria, C. L. Sampaco, and M. C. Alfaro

Closure to “Discussion on ‘Prediction of Embankment Settlements by In-Situ Tests,’ by M Gambin” by D. T. Bergado, P. M. Daria, C. L. Sampaco, and M. C. Alfaro

Discussion on “Prediction of Embankment Settlements by In-Situ Tests,” by D. T. Bergado, P. M. Daria, C. L. Sampaco, and M. C. Alfaro

Discussion on “Prediction of Embankment Settlements by In-Situ Tests,” by D. T. Bergado, P. M. Daria, C. L. Sampaco, and M. C. Alfaro

Prediction of Embankment Settlements by In-Situ Tests

Abstract The compressibility of soft Bangkok clay preloaded with an instrumented test embankment was studied using the results of a series of in-situ and laboratory tests. In the field, eight screw plate and eight pressuremeter tests were performed at four test levels in the subsoil. In the laboratory, twelve Rowe cell consolidation tests were carried out. The method of Asaoka (1978) was used in determining the coefficient of consolidation from the screw plate test. It was found that Cv values obtained from the Rowe cell consolidation tests were twelve times smaller compared to those derived from the screw plate tests. The soil parameters obtained from the two types of in-situ tests conducted in this study were then used to predict the settlement behavior of the two test embankments, one improved by prefabricated vertical drains (PVD), and the other, on unimproved ground. The difficulty associated with the proper choice of the drained modulus values are highlighted, and it was found that the predicted settlement magnitudes using elastic theory can vary considerably for the ratio of drained and undrained soil moduli, E′/Eu, ranging between 0.25 to 0.50. The undrained modulus from the screw plate test corresponding to the fitted data was found to be 1.38 times the undrained modulus from the pressuremeter test. General agreement with the observed settlement was found using the graphical procedure of Asaoka (1978) and adopting the coefficient of consolidation from the screw plate test.