A bridge foundation analysis

Gradjevinski materijali i konstrukcije, 2019

Proceedings of The Institution of Civil Engineers-geotechnical Engineering, 2006

The Crozet bridge is located on the Grenoble-Col du Fau motorway, on the Grenoble-Sisteron route, fifteen kilometres south of Grenoble, France. It crosses a 350 m wide valley and the RN75 national road. The adaptation of the bridge into the landscape has involved an arch design with three bays (direction Grenoble-Sisteron) and one bay (direction Sisteron-Grenoble). The supports of the structure were difficult to build because of the huge horizontal force and the low displacement tolerance. The low stiffness and strength characteristics foreseen led to a geotechnical investigation by cyclic pressuremeter tests with a friction angle and cohesion interpretation. The foundation calculations were carried out by a Finite Element calculation using CESAR-LCPC program to determine the support rigidity. The complete computation of the bridge was done with the calculated support rigidity which showed that displacements of the arches were lower than the tolerance. The bridge is located in low seismic area of France and the design takes into account the maximum foreseeable magnitude, and analysis of the soil liquefaction risk. Monitoring carried out for completion of the bridge in 1999 and along the surveying shows displacements lower than tolerance values. Since 1999, the bridge has withstood huge service weights without any difficulty.

Transportation in the New Millennium, 2000

WIT Transactions on the Built Environment, 1970

In the design of a structure, the implementation of reliable soil-foundationstructure interaction into the analysis process plays a very important role. The paper presents a determination of parameters of a suitably chosen soilfoundation model and their influence on the structure response. Since the mechanical data for the structure can be determined with satisfactory accuracy. the properties of the soil-foundation model were identified using measured dynamic response of the real structure. A simple model describing soilfoundation structure was incorporated into the classical 3-D finite element analysis of the structure with commercial software. Results obtained from the measured data on the pier were afterwards compared with those obtained with the finite model of the pier-foundation-soil structure. On the basis of this comparison the coefficients describing the properties in the soil-foundation model were adjusted until the calculated dynamic response coincided with the measured ones. In this way, the difference between both results was reduced to 1%. Full-scale tests measuring eigenmotion of the bridge were performed through all erection stages of the new bridge in Maribor. In this way an effective and experimentally verified 3-D model for a complex dynamic analysis of the bridge under the earthquake loading was obtained. The significant advantage of the obtained model is that it was updated on the basis of the dynamic measurements thus improving the model on the basis of in-situ geomechanical measurements. The model is very accurate in describing the upper structure and economical in describing the soil mass thus representing an optimal solution regarding computational efforts.

2017

This article presents a comparative study by numerical analysis of the behavior of reinforcements of clayey soils by flexible columns (stone columns) and rigid columns (piles). The numerical simulation was carried out in 3D for an assembly of foundation, columns and a pile of a bridge. Particular attention has been paid to take into account the installation of the columns. Indeed, in practice, due to the compaction of the column, the soil around it sustains a lateral expansion and the horizontal stresses are increased. This lateral expansion of the column can be simulated numerically. This work represents a comparative study of the interaction between the soil on one side, and the two types of reinforcement on the other side, and their influence on the behavior of the soil and of the pile of a bridge.

Revista de la construcción

Bridges projects, usually considered a wide range of geotechnical research for the design of foundations. These works are of considerable importance for the proper design of foundations (shallow or deep) as well as to avoid problems during the project execution (time, cost, safety, complementary campaigns, etc.). This paper aims to analyze criteria and minimum geotechnical requirements for the project development of traditional and long-span bridges in Chile, taking into account international and national experience, considering as case of study the Project of Design and Construction of Chacao Bridge: multi-span suspension bridge with two main spans, 1,055 m and 1,155 m, currently underway in southern Chile, as a result of this work a summary of the minimum geotechnical requirements needed is proposed.

Gradjevinski materijali i konstrukcije

iv I hereby declare that all information in this document has been obtained and presented in accordance with academic rules and ethical conduct. I also declare that, as required by these rules and conduct, I have fully cited and referenced all material and results that are not original to this work. Name, Last name : Ekin AKKAYA Signature : v ABSTRACT AN INVESTIGATION OF SEISMIC BEHAVIOUR OF MULTI-SPAN BRIDGES ON SHALLOW FOUNDATIONS WITH SOIL-STRUCTURE INTERACTION METHODS Akkaya, Ekin M.Sc., Department of Civil Engineering Supervisor: Prof. Dr. Bahadır Sadık Bakır September 2013, 85 pages

Soil Dynamics and Earthquake Engineering, 2015

The dynamic response of vehicular overpasses with massive foundations built in highly populated earthquake prone regions is studied to assess the massive foundation potential of being a technically sound mean to reduce the structural response during major earthquakes. The study consists on numerical simulations using 3-D finite element models. Two typical supports of a major 23 km long vehicular overpass recently built in the north east part of Mexico City valley were considered in this research. This zone is characterized by the presence of stiff soils comprised by dense and very dense silty sands and sandy silts, randomly intercalated by stiff clays layers of variable thickness. Initially, a conventional raft foundation structurally connected to four precast closed-end concrete piles was considered. Then, the potential beneficial effect of a massive foundation of variable depth was assessed. Sets of 3-D finite element models were developed and the response of the systems was evaluated for a typical seismic scenario such as that prevailing at the zone, assuming a potential 8.1 M w seismic event, and for a hypothetical 8.7 M w extreme event. Important attenuations of about 39% to 48% at the upper deck spectral accelerations and of 21% to 30% in maximum lateral foundation displacements were achieved with the massive soil improvement for the cases analyzed. Thus, the massive foundations seem to be a convenient alternative to reduce the overall structural seismic response.