Horasan Mortar Bearings in Base Isolation with Centuries Experiences

Abstract

The purpose of this study is to demonstrate the applicability of the Horasan mortar friction interface, which has been used for many long years in the past historical periods, as a seismic isolator in lightweight building structures with no overturning moment. To this end a four-storey hospital building has been selected as an example. Using the beyond-linear mathematical model simulation the results for Horasan mortar, stainless steel, gray-iron/mortar friction interfaces have been compared. For each interface the base acceleration is seen to be reduced in the ratio of 45, 38, 33% compared to the built-in building. For complete these favorable results-NSI device’s material stress- and strain rang assessment have been modeled by the FEM in ANSYS, LS-DYNA environments and compute results to be compared to the related material ultimate values. Generally different devices are used to restore the superstructure to the initial position. In this study it has been proven that the earthquake has a restoring property and this phenomena have been used as the indirect restoring device. Full details of the application of Horasan mortar, which is economically favorable and has been used for many centuries in the history as a friction interface, has been given.

Appendix

Figs. (3.24–3.36) Ls-Dyna software modeling response results of the four story building with the NSI devices with Horasan mortar sliding base interface under Duzce/Turkey, 1999 earthquake for time 10.83 s: Fig. (3.24) Horasan Mortar’s Von Mises stress; Fig. (3.25) Superstructure beams axial forces; Fig. (3.26) Superstructure beams tor-sional forces; Fig. (3.27) Superstructure beams bending moments in section S direction; Fig. (3.28) Superstructure beams bending moments in section T direction; Fig. (3.29) Superstructure beams shear forces in section S direction; Fig. (3.30) Superstructure beams shear forces in section T direction; (Fig. 3.31) Averaged base level (green) acceleration; (Fig. 3.32) Averaged base level (green) velocity; (Fig. 3.33) Averaged base level (green) displacement; (Fig. 3.34) Averaged base level (pinkish) and toplevel (yellow) acceler-ations; (Fig. 3.35) Averaged base level (pinkish) and top-level (yellow) velocities; (Fig. 3.36) Averaged base level (pinkish) and top level (yellow) displacement.

Fig. 3.24

Superstructure beams axial forces

Fig. 3.25

Horasan Mortar’s Von Mises stress

Fig. 3.26

Superstructure beams torsional forces

Fig. 3.27

Superstructure beams bending moments in section S direction

Fig. 3.28

Superstructure beams bending moments in section T direction

Fig. 3.29

Superstructure beams shear forces in section S direction

Fig. 3.30

Superstructure beams shear forces in section T direction

Fig. 3.31

Averaged base level (green) acceleration

Fig. 3.32

Averaged base level (green) velocity

Fig. 3.33

Averaged base level (green) displacement

Fig. 3.34

Averaged base level (pinkish) and top-level (yellow) accelerations

Fig. 3.35

Averaged base level (pinkish) and top-level (yellow) velocities

Fig. 3.36

Averaged base level (pinkish) and top level (yellow) displacements