Monitoring of a rehabilitated building in soft soil in Mexico and structural response to September 2017 earthquakes: Part 2: Numerical simulation

Abstract

This article deals with the proper numerical simulation of the response presented by an instrumented damaged-retrofitted building using a low computational cost linear-elastic model, using effective stiffness for its reinforced concrete structural members. The purpose is to identify the most appropriate criteria and considerations and to validate them against the actual behavior of the building registered during real earthquakes. Relevant structural aspects like concrete elastic modulus and soil–structure interaction effects are determined experimentally. Special attention is paid to select appropriate techniques to model the complex geometry of the North-South facades wall elements and their related coupling beams. Finally, time-history analyses of 20 March 2012 earthquake (service conditions demand) and 19 September 2017 earthquake (design conditions demand) are performed, both considering and ignoring the soil–structure interaction effects. Results point out that commonly adopted simplifications in numerical models of buildings must be correctly implemented to satisfactorily simulate their earthquake response.

Monitoring of a rehabilitated building in soft soil in Mexico and structural response to the September 2017 earthquakes: Part 1: structural health monitoring system

“…This good correlation suggests that such parameters can be used to detect damage and the occurrence of a cumulative damage process. In a companion paper (Murià-Vila et al, 2020), a numerical simulation of the seismic response of the CCUT tower is presented based on the 19 September 2017 records. Calculated interstory drift ratios are compared with the experimental values.…”

“…In addition, 36 new control piles were added to the foundation box extension in the south side during the 1987 retrofit, leaving a total amount of 88 control RC end-bearing piles added to the original foundation. Control end-bearing piles present a height regulation mechanism in the slab-pile connection (see Figures 2 and 3 of Part 2 paper, Murià-Vila et al, 2020).…”

“…The kSSI effects differ slightly between the moderate-and high-intensity events 12-1 and 17-2. This fact has implications over the stiffness calculated from the registers and are explained and presented in the Part 2 paper that deals with the numerical simulation in order to reproduce the responses recorded in the tower (Murià-Vila et al, 2020). In the Nakamura ratios (Figure 8), a kSSI is also detected when comparing the amplitudes between the basement of the tower (B-SW) and that of the structure II (CB-NW), as well as between these two basement sites and the field station (S).…”

“…The complexity of the foundation in the CCUT building represents a difficulty to estimate the SSI stiffness using conventional analytical methods. However, since the response at the base of the tower was recorded, the horizontal and rocking stiffness responses associated with the SSI effects, during moderate-and high-intensity earthquakes, can be calculated according to the proposed methodology discussed in Part 2 of this issue (Murià-Vila et al, 2020).…”

“…The structure is the 22-story tower of the CCUT complex constructed in 1964 and located in the soft soil zone of Mexico City. In a companion paper, Part 2 (Murià-Vila et al, 2020), the numerical simulation of the seismic response of the structure is described.…”