th 11 International Conference on Earthquake Resistant Engineering Structures Protection of Masonry Housing in High Seismic Zones with Low-Cost Rubber Isolators Ahmad Basshofi Habieb¹, Gabriele Milani¹, Tavio², Federico Milani ³ ¹ABC Department, Politecnico di Milano, Italy ²Institut Teknologi Sepuluh Nopember, Indonesia ³Chem.co Consultant, Occhiobello, Italy 5-7 July 2017 Alicante, Spain

Great Earthquakes in Indonesia Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Background Great Earthquakes in Indonesia ACEH 9.2 Mw earthquake in 2004 followed by tsunami 250.000 dead PADANG 7.6 Mw earthquake in 2009 1.115 dead JOGJAKARTA 6.4 Mw earthquake in 2006 6.500 dead ABC DEPARTMENT - POLITECNICO DI MILANO

Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Background Many developing countries have high-risk seismic zones Low-class housings in developing countries are often not engineered masonry structures are commonly found in rural areas source: Teddy Boen (2013) ABC DEPARTMENT - POLITECNICO DI MILANO

Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Background Base Isolation is considered as an effective method to improve the seismic behavior of structures thick steel plate high damping rubber steel layer reinforcement Massive utilization of conventional seismic isolator costs too much for low-class housing ABC DEPARTMENT - POLITECNICO DI MILANO

Vision of this research Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Vision of this research Develop low-cost isolation system from rubber materials and practical guidelines of its application for housing in developing countries ABC DEPARTMENT - POLITECNICO DI MILANO

Preliminary design of isolator (Target properties) Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Preliminary design of isolator (Target properties) 150 x 150 x 54 5 x tr 4 x tf FREI - 150 100 x 100 x 54 5 x tr 4 x tf FREI - 100 fiber lamina reinforce. no thick steel plate Rubber A Shore Hardness = 20-40 Thickness of rubber (tr) = 10 mm Thickness of fiber (tf) = 1 mm Vertical load range = 1 – 4 MPa Max. horizontal deform = 1.75 x tr total Eff. Damping ratio = 5 - 10 % Unbonded application FREI - 200 200 x 200 x 76 7 x tr 6 x tf ABC DEPARTMENT - POLITECNICO DI MILANO

Modeling Low Cost Rubber Isolator Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al ICCMSE 2017 Modeling Low Cost Rubber Isolator carbon fiber with E = 40 GPa C3D8R element Equivalent to rubber with shore A hardness = 40 ABC DEPARTMENT - POLITECNICO DI MILANO

Modeling Low Cost Rubber Isolator Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Modeling Low Cost Rubber Isolator Excessive tensile stress roll-over Increase the damping ratio (can have 10 %) roll-over Permanent sliding damage of isolators Horizontal behavior of FREI in bonded, unbonded, and frictional conditions The unbonded one seems the most suitable type for low cost isolation system ABC DEPARTMENT - POLITECNICO DI MILANO

Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al ICCMSE 2017 MODELLING ISOLATORS Experimental Results of FREI-200 (Toopchi-Nezhad et al, 2008) Numerical model of FREI-200 with 10% damping ABC DEPARTMENT - POLITECNICO DI MILANO

ISOLATORS FOR MASONRY STRUCTURES Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al ICCMSE 2017 ISOLATORS FOR MASONRY STRUCTURES masonry Concrete beam Rubber isolator foundation Application of rubber isolators for masonry ABC DEPARTMENT - POLITECNICO DI MILANO

ISOLATORS FOR MASONRY STRUCTURES Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al ICCMSE 2017 ISOLATORS FOR MASONRY STRUCTURES First prototype of isolated masonry with unbonded FREI in Tawang, India. (Van Ngo Thuyet et al, 2017) ABC DEPARTMENT - POLITECNICO DI MILANO

Damping ratio 10% (high damping thanks to the unbonded application) Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Numerical simulations of 2-story masonry housing isolated with low-cost seismic isolators (FREI-150) Thickness of the wall 30 cm Max vertical load 3.2 MPa Damping ratio 10% (high damping thanks to the unbonded application) Step = 1.33 m ABC DEPARTMENT - POLITECNICO DI MILANO

Concrete damage plasticity Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al ICCMSE 2017 Masonry FE Model Concrete damage plasticity = 1300 MPa

Modal analysis Without isolation With isolation A. B. Habieb et al Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Modal analysis Without isolation With isolation ABC DEPARTMENT - POLITECNICO DI MILANO

DS 2 : moderate damage Drift 0.1 % Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Numerical Simulations Static pushover analysis of isolated 2 story masonry housing Isolator unstable DS 2 : moderate damage Drift 0.1 % DS 3 : extensive damage Drift 0.3 % DS 4 : Collapse Drift 0.5 %  Calvi et al, 1999

Numerical Simulations Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Numerical Simulations 3D Non-linear Dynamic Analysis (in case of L’Aquila accelerogram 0.6g) no DS 3 in the isolated model ABC DEPARTMENT - POLITECNICO DI MILANO

Isolated model at the end of test Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Numerical Simulations 3D Non-linear Dynamic Analysis (in case of L’Aquila accelerogram 0.6g) DS 2 (both models) Isolated model at the end of test DS 3 (no-isolation) DS 4 (no-isolation) Then, we have to monitor the shear behavior of rubber isolators during ground motion ABC DEPARTMENT - POLITECNICO DI MILANO

Control of isolators V F Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Control of isolators Monitoring the behavior of isolators to check if the deformation limit is reached (when the isolator becomes unstable) V F Full contact deformation  isolator unstable Critical bearing area buckling of isolator Also, the isolators may exhibit deformation with some inclinations ABC DEPARTMENT - POLITECNICO DI MILANO

Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Control of isolators Behaviors of unbonded FREI-150 in different angles of shear deformation during L’Aquila earthquake Ut = maximum deformation occurred during ground motion Ucrit = deformation limit, when the isolator becomes unstable due to full contact deformation Deformation limit is generally about 175% x tr = 87 mm (without inclination) With more inclination, the deformation limit decreases

Results On going research Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Results The isolators proposed less expensive than the commercial devices. Isolation system proposed can reduce significantly the damage of masonry housing FREI 150 are suitable for two-story masonry housing, the case of seismic motion with PGA=0.6g The isolator proposed satisfies the limit of horizontal displacement due to earthquake On going research Experimental validations Evaluating the performance of isolated building according to Indonesian seismic code ABC DEPARTMENT - POLITECNICO DI MILANO

THANK YOU

Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Research Products Prototypes of Low-cost fiber reinforced elastomeric isolator (FREI) Technological procedures of FREI fabrication Technical guidelines of isolation system for housing using low cost FREI ABC DEPARTMENT - POLITECNICO DI MILANO

Objectives Understand the behavior of rubber isolators Low cost rubber seismic isolator for housing in development countries A. B. Habieb et al Objectives Understand the behavior of rubber isolators Develop numerical models and validate through experimental works Understand the fabrication process of rubber isolators Optimize the composition of rubber and fiber materials for isolators Develop practical guidelines of low-cost rubber isolation system for housing http://www.usrubber.com/assets/images/img-23.jpg Turer and Ozden, 2008 ABC DEPARTMENT - POLITECNICO DI MILANO