Keywords: Fondation ; Mur de soutenement ; Pieux ; Capacite portante ; Ancrage ; Dimensionnement Reference Record created on 2004-09-07, modified on 2016-08-08

During the years 2008 to 2010 it will be constructing in Spain the new railway line of high velocity trains that will connect Valladolid with the northwest of Spain. One of the first phases comprises the connection of provinces Palencia and Leon with a train of 300 km/h of speed. The new phase with an inversion of 22 million Euros will cross the provinces of Palencia and Leon in direction to Galicia on the North West of Spain. This phase comprises 5 great viaducts from 116 to 450 meters. The present paper exposes the project and construction of one of the most singular bridge which crosses above the existing motorway M-31. The solution of the bridge has been made “in pergola” according with the Spanish terminology. The project of the bridge called “Pergola over the existing motorway M-31” was realized by means of a complete three-dimensional model of finite elements with the program SAP2000N that includes all the elements of the structure, that is, sub-structure comprising foundations made with piles (4500 m of piles), mat foundations tying the piles, pillars, and the superstructure comprising a prestressed concrete slab, and the complete abutments. The length of the bridge is 156 m with a width of 14.5 m. The 3D finite element model of the complete bridge made with SAP2000N comprises 8806 nodes, 6366 frame elements and 2326 shell elements and the number of hypothesis studied was 1306 with static and dynamic situations.

/pdf/large-bridge-in-pergola-for-high-speed-trains-to-the-2o6ze07x4s.pdf

Foundation analysis and design

Large bridge “in pérgola” for high speed trains to the northwest of Spain

Over 100 centrifuge tests were conducted to assess Load and Resistance Factor Design (LRFD) resistance factors for external stability of Mechanically Stabilized Earth (MSE) walls founded on granular soils. In the case of sliding stability, the tests suggest the LRFD Φ values vary from 0.74 to 0.94 and 0.63 to 0.68 using Rankine and Coulomb methods for lateral resultant force, respectively. These values covered wall heights of 8 to 14 ft with variable backfill having μφ=32° and CVφ= 11.7%. The study also revealed that the load factor for horizontal earth pressure agreed very well with current practice (AASHTO, 2012), i.e. 1.5. In the case of bearing stability, the tests support Φ= 0.47 and 0.45 (β= 3.09) for foundation soils with μφ= 26°-30° and 31°-33°, respectively, and Φ= 0.65 and 0.68 (β= 2.32); current practice uses Φ= 0.65. The tests also suggest the use of load inclination factors in estimating bearing capacity. The combination of axial and lateral force, i.e., inclined resultant reduces the depth and length of the bearing failure surface, which is reflected in a reduced capacity. From over 200 measurements, the load factor for vertical earth pressure was determined to be 1.87, which is larger than current practice, 1.35 (AASHTO, 2012), but agrees well with values reported by others for internal stability. In the case of bearing stability of MSE walls near slopes, it was found that current prediction methods (Bowles, Vesic, etc.) are too conservative. Moreover, based on observed failures of MSE walls near embankments, slope stability instead of bearing controls their design

background or methods

https://rosap.ntl.bts.gov/view/dot/26847/dot_26847_DS1.pdf

Development of LRFD Resistance Factors for Mechanically Stabilized Earth (MSE) Walls

Analysis of reinforced concrete floor slabs for storm shelters

The North Carolina State Ports Authority (NCSPA) has undertaken improvements to its Morehead Port berth facilities, to better serve the deeper draft vessels utilized in today's shipping industry. In general, the improvements include a layer of tieback to aid in carrying additional live loads from a recently constructed warehouse, and a combination of additional layers of tiebacks and a king pile wall system to stabilize the existing wall during the future removal of an existing rock berm and dredging along approximately 213.4 meters (700 feet) of the mudline to a deeper elevation. The Ports Authority commissioned an engineering study to determine a feasible approach to accomplish the improvements. The engineering study included a subsurface exploration to assess the subsurface profile, engineering properties of the in-situ soils, and configuration of an existing relieving platform behind the current wall system. The subsurface profile model was utilized in a detailed soil-structure interaction (SSI) analysis to design the new wall system. The design of the new wall system implemented innovative methodologies and construction sequencing to minimize the effects of the new wall on the existing wall system and warehouse. This paper highlights key features of the project. It describes the background information; project description; the design methodologies; soil exploration and determination of engineering parameters used in the SSI analysis of the new wall system; and incorporation of practical construction issues in the design. Copyright 2010 ASCE.

Foundation analysis and design

Citations

Large bridge “in pérgola” for high speed trains to the northwest of Spain

Development of LRFD Resistance Factors for Mechanically Stabilized Earth (MSE) Walls

Analysis of reinforced concrete floor slabs for storm shelters

Evaluation and design for wharf berth improvements

Sustainability analysis of the tall asymmetrical building

Related Papers (5)

Soil mechanics in engineering practice

Theoretical Soil Mechanics

Pile Foundation Analysis and Design

Principles of Foundation Engineering

Analysis of Ultimate Loads of Shallow Foundations