Soil failure can be used for seismic protection of structures

I. Anastasopoulos, G. Gazetas, M. Loli, M. Apostolou, N. Gerolymos

    Research output: Contribution to journalArticle

    105 Citations (Scopus)

    Abstract

    A new seismic design philosophy is illuminated, taking advantage of soil "failure" to protect the superstructure. Instead of over-designing the foundation to ensure that the loading stemming from the structural inertia can be "safely" transmitted onto the soil (as with conventional capacity design), and then reinforce the superstructure to avoid collapse, why not do exactly the opposite by intentionally under-designing the foundation to act as a "safety valve"? The need for this "reversal" stems from the uncertainty in predicting the actual earthquake motion, and the necessity of developing new more rational and economically efficient earthquake protection solutions. A simple but realistic bridge structure is used as an example to illustrate the effectiveness of the new approach. Two alternatives are compared: one complying with conventional capacity design, with over-designed foundation so that plastic "hinging" develops in the superstructure; the other following the new design philosophy, with under-designed foundation, "inviting" the plastic "hinge" into the soil. Static "pushover" analyses reveal that the ductility capacity of the new design concept is an order of magnitude larger than of the conventional design: the advantage of "utilising" progressive soil failure. The seismic performance of the two alternatives is investigated through nonlinear dynamic time history analyses, using an ensemble of 29 real accelerograms. It is shown that the performance of both alternatives is totally acceptable for moderate intensity earthquakes, not exceeding the design limits. For large intensity earthquakes, exceeding the design limits, the performance of the new design scheme is proven advantageous, not only avoiding collapse but hardly suffering any inelastic structural deformation. It may however experience increased residual settlement and rotation: a price to pay that must be properly assessed in design.
    Original languageEnglish
    Pages (from-to)309-326
    Number of pages18
    JournalBulletin of Earthquake Engineering
    Volume8
    Issue number2
    DOIs
    Publication statusPublished - Apr 2010

    Fingerprint

    soils
    Soils
    soil
    earthquakes
    earthquake intensity
    Earthquakes
    plastic
    plastics
    Plastics
    Safety valves
    earthquake
    bridges (structures)
    Seismic design
    seismic design
    ductility
    Hinges
    hinges
    inertia
    stems
    Ductility

    Cite this

    Anastasopoulos, I., Gazetas, G., Loli, M., Apostolou, M., & Gerolymos, N. (2010). Soil failure can be used for seismic protection of structures. Bulletin of Earthquake Engineering, 8(2), 309-326. https://doi.org/10.1007/s10518-009-9145-2
    Anastasopoulos, I. ; Gazetas, G. ; Loli, M. ; Apostolou, M. ; Gerolymos, N. / Soil failure can be used for seismic protection of structures. In: Bulletin of Earthquake Engineering. 2010 ; Vol. 8, No. 2. pp. 309-326.
    @article{ee8f88b9ad304500912ace552391b983,
    title = "Soil failure can be used for seismic protection of structures",
    abstract = "A new seismic design philosophy is illuminated, taking advantage of soil {"}failure{"} to protect the superstructure. Instead of over-designing the foundation to ensure that the loading stemming from the structural inertia can be {"}safely{"} transmitted onto the soil (as with conventional capacity design), and then reinforce the superstructure to avoid collapse, why not do exactly the opposite by intentionally under-designing the foundation to act as a {"}safety valve{"}? The need for this {"}reversal{"} stems from the uncertainty in predicting the actual earthquake motion, and the necessity of developing new more rational and economically efficient earthquake protection solutions. A simple but realistic bridge structure is used as an example to illustrate the effectiveness of the new approach. Two alternatives are compared: one complying with conventional capacity design, with over-designed foundation so that plastic {"}hinging{"} develops in the superstructure; the other following the new design philosophy, with under-designed foundation, {"}inviting{"} the plastic {"}hinge{"} into the soil. Static {"}pushover{"} analyses reveal that the ductility capacity of the new design concept is an order of magnitude larger than of the conventional design: the advantage of {"}utilising{"} progressive soil failure. The seismic performance of the two alternatives is investigated through nonlinear dynamic time history analyses, using an ensemble of 29 real accelerograms. It is shown that the performance of both alternatives is totally acceptable for moderate intensity earthquakes, not exceeding the design limits. For large intensity earthquakes, exceeding the design limits, the performance of the new design scheme is proven advantageous, not only avoiding collapse but hardly suffering any inelastic structural deformation. It may however experience increased residual settlement and rotation: a price to pay that must be properly assessed in design.",
    author = "I. Anastasopoulos and G. Gazetas and M. Loli and M. Apostolou and N. Gerolymos",
    note = "Copyright 2010 Elsevier B.V., All rights reserved.",
    year = "2010",
    month = "4",
    doi = "10.1007/s10518-009-9145-2",
    language = "English",
    volume = "8",
    pages = "309--326",
    journal = "Bulletin of Earthquake Engineering",
    issn = "1570-761X",
    publisher = "Springer Verlag",
    number = "2",

    }

    Anastasopoulos, I, Gazetas, G, Loli, M, Apostolou, M & Gerolymos, N 2010, 'Soil failure can be used for seismic protection of structures', Bulletin of Earthquake Engineering, vol. 8, no. 2, pp. 309-326. https://doi.org/10.1007/s10518-009-9145-2

    Soil failure can be used for seismic protection of structures. / Anastasopoulos, I.; Gazetas, G.; Loli, M.; Apostolou, M.; Gerolymos, N.

    In: Bulletin of Earthquake Engineering, Vol. 8, No. 2, 04.2010, p. 309-326.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - Soil failure can be used for seismic protection of structures

    AU - Anastasopoulos, I.

    AU - Gazetas, G.

    AU - Loli, M.

    AU - Apostolou, M.

    AU - Gerolymos, N.

    N1 - Copyright 2010 Elsevier B.V., All rights reserved.

    PY - 2010/4

    Y1 - 2010/4

    N2 - A new seismic design philosophy is illuminated, taking advantage of soil "failure" to protect the superstructure. Instead of over-designing the foundation to ensure that the loading stemming from the structural inertia can be "safely" transmitted onto the soil (as with conventional capacity design), and then reinforce the superstructure to avoid collapse, why not do exactly the opposite by intentionally under-designing the foundation to act as a "safety valve"? The need for this "reversal" stems from the uncertainty in predicting the actual earthquake motion, and the necessity of developing new more rational and economically efficient earthquake protection solutions. A simple but realistic bridge structure is used as an example to illustrate the effectiveness of the new approach. Two alternatives are compared: one complying with conventional capacity design, with over-designed foundation so that plastic "hinging" develops in the superstructure; the other following the new design philosophy, with under-designed foundation, "inviting" the plastic "hinge" into the soil. Static "pushover" analyses reveal that the ductility capacity of the new design concept is an order of magnitude larger than of the conventional design: the advantage of "utilising" progressive soil failure. The seismic performance of the two alternatives is investigated through nonlinear dynamic time history analyses, using an ensemble of 29 real accelerograms. It is shown that the performance of both alternatives is totally acceptable for moderate intensity earthquakes, not exceeding the design limits. For large intensity earthquakes, exceeding the design limits, the performance of the new design scheme is proven advantageous, not only avoiding collapse but hardly suffering any inelastic structural deformation. It may however experience increased residual settlement and rotation: a price to pay that must be properly assessed in design.

    AB - A new seismic design philosophy is illuminated, taking advantage of soil "failure" to protect the superstructure. Instead of over-designing the foundation to ensure that the loading stemming from the structural inertia can be "safely" transmitted onto the soil (as with conventional capacity design), and then reinforce the superstructure to avoid collapse, why not do exactly the opposite by intentionally under-designing the foundation to act as a "safety valve"? The need for this "reversal" stems from the uncertainty in predicting the actual earthquake motion, and the necessity of developing new more rational and economically efficient earthquake protection solutions. A simple but realistic bridge structure is used as an example to illustrate the effectiveness of the new approach. Two alternatives are compared: one complying with conventional capacity design, with over-designed foundation so that plastic "hinging" develops in the superstructure; the other following the new design philosophy, with under-designed foundation, "inviting" the plastic "hinge" into the soil. Static "pushover" analyses reveal that the ductility capacity of the new design concept is an order of magnitude larger than of the conventional design: the advantage of "utilising" progressive soil failure. The seismic performance of the two alternatives is investigated through nonlinear dynamic time history analyses, using an ensemble of 29 real accelerograms. It is shown that the performance of both alternatives is totally acceptable for moderate intensity earthquakes, not exceeding the design limits. For large intensity earthquakes, exceeding the design limits, the performance of the new design scheme is proven advantageous, not only avoiding collapse but hardly suffering any inelastic structural deformation. It may however experience increased residual settlement and rotation: a price to pay that must be properly assessed in design.

    UR - http://www.scopus.com/inward/record.url?scp=77952879493&partnerID=8YFLogxK

    U2 - 10.1007/s10518-009-9145-2

    DO - 10.1007/s10518-009-9145-2

    M3 - Article

    AN - SCOPUS:77952879493

    VL - 8

    SP - 309

    EP - 326

    JO - Bulletin of Earthquake Engineering

    JF - Bulletin of Earthquake Engineering

    SN - 1570-761X

    IS - 2

    ER -