Cyclic Behaviour of Expanded Polystyrene (EPS) Sandwich Reinforced Concrete Walls

Ari Wibowo,Christin R Nainggolan,Indradi Wijatmiko

doi:10.1155/2018/7214236

Ari Wibowo, Christin R Nainggolan + Show 1 more

Open Access

https://doi.org/10.1155/2018/7214236

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Abstract

Precast concrete walls become increasingly utilized due to the rapid needs of inexpensive fabricated house especially as traditional construction cost continues to climb, and also, particularly at damaged area due to natural disasters when the requirement of a lot of fast-constructed and cost-efficient houses are paramount. However, the performance of precast walls under lateral load such as earthquake or strong wind is still not comprehensively understood due to various types of reinforcements and connections. Additionally, the massive and solid wall elements also enlarge the building total weight and hence increase the impact of earthquake significantly. Therefore, the precast polystyrene-reinforced concrete walls which offer light weight and easy installment became the focus of this investigation. The laboratory test on two reinforced concrete wall specimens using EPS (expanded polystyrene) panel and wire mesh reinforcement has been conducted. Quasi-static load in the form of displacement controlled cyclic tests were undertaken until reaching peak load. At each discrete loading step, lateral load-deflection behaviour, crack propagation, and collapse mechanism were measured which then were compared with theoretical analysis. The findings showed that precast polystyrene-reinforced concrete walls gave considerable seismic performance for the low-to-moderate seismic region reaching up to 1% drift at 20% drop of peak load. However, it might not be sufficient for high seismic regions, at which double-panel wall type can be more suitable.

Highlights

Tall buildings with irregularities are prone to behave poorly and collapse when subjected to lateral loads such as earthquake excitation or strong wind
Hejin et al [3] focused on ash ceramsite as alternative for lightweight aggregate concrete shear wall which gave similar load-deflection behaviour and collapse mechanism to those on normal concrete ones, whereas Chai and Anderson [4] found that the performance of concrete wall panels using perforated lightweight aggregate in low-rise buildings subjected to lateral forces was generally satisfactory
Two specimens of light-weight sandwich concrete walls have been tested in order to investigate the lateral load-drift behaviour and collapse mechanism

Summary

Introduction

Tall buildings with irregularities are prone to behave poorly and collapse when subjected to lateral loads such as earthquake excitation or strong wind To overcome this problem, shear walls are commonly preferable to increase the lateral strength of structures significantly. Ere were many studies investigating lightweight concrete shear walls with various techniques to reduce the element weight such as using lightweight aggregates, applying porous concrete system, or inserting lightweight panel into the wall. Previous experimental studies by Trombetti et al [15] and Ricci et al [16] showed that sandwich squat concrete walls were comparable to those of regular RC walls and able to sustain lateral load up to drift higher than 1.3%, whereas Palermo and Trombetti [17] comprehensively investigated sandwich walls experimentally and analytically with the outcomes showed that properly designed walls can accomplish high seismic performance requirement suggested by the code. At each defined discrete displacement stages, the measurement of LVDTs, dial gauges, and crack propagation were recorded. e test stopped when the peak lateral strength of the specimen reduced by 20% (lateral load failure)

Experimental Test Results

Backbone Curve Models

Model 1

Model 2

D Figure 12

Conclusion