Improving structural performance of timber wall panels by inexpensive FRP retrofitting techniques

Abstract This paper presents an experimental investigation conducted on traditional timber structures, known as Dhajji Dewari (DD). These timber structures are mostly constructed in mountainous regions and other places where availability of conventional building construction materials is scarce. DD has prominent features such as its ability to resist lateral forces, but there has been little work done on the retrofitting aspect of DD structures. In this experimental study, 5 reduced scale DD wall samples have been tested, in two phases, for structural performance. The walls were tested under in-plane lateral monotonic loading, and their response was then evaluated. In the 1st phase of testing, conventional strengthening techniques were used to find the progressive joint failure pattern, while in the 2nd phase of testing, those damaged critical joints were retrofitted with CFRP. It was demonstrated that by using FRP for wall retrofitting, not only is the load and displacement carrying capacity of the wall enhanced, but its ductility and energy dissipation are also significantly improved, thereby validating the seismic performance of DD construction.

[1]  T. Paulay,et al.  Seismic Design of Reinforced Concrete and Masonry Buildings , 1992 .

[2]  FRP in construction: Applications, advantages, barriers and perspectives , 2001 .

[3]  Muhammad Usman,et al.  Effect of Steel Confinement on Axially Loaded Short Concrete Columns , 2018, IOP Conference Series: Materials Science and Engineering.

[4]  J. Lees,et al.  Nonlaminated FRP Strap Elements for Reinforced Concrete, Timber, and Masonry Applications , 2011 .

[5]  Nicholas A. Dembsey,et al.  Thermal and Fire Characteristics of FRP Composites for Architectural Applications , 2015 .

[6]  C. Leung,et al.  Graphene oxide modified Strain Hardening Cementitious Composites with enhanced mechanical and thermal properties by incorporating ultra-fine phase change materials , 2019, Cement and Concrete Composites.

[7]  Muhammad Usman,et al.  Retrofitting of damaged reinforced concrete bridge structure , 2019 .

[8]  Robert Kliger,et al.  FRP reinforcement of timber structures , 2015 .

[9]  Xianglin Gu,et al.  Compressive Behavior of Longitudinally Cracked Timber Columns Retrofitted Using FRP Sheets , 2012 .

[10]  Amr S. Elnashai,et al.  The Kashmir earthquake of October 8, 2005 : a quick look report , 2005 .

[11]  Zechuan Yu,et al.  Effect of moisture on the mechanical properties of CFRP–wood composite: An experimental and atomistic investigation , 2015 .

[12]  François W. Kropf,et al.  Strengthening, Retrofitting and Upgrading of Timber Structures with High-Strength Fibres , 2000 .

[13]  José S. Machado,et al.  The use of FRP in the strengthening of timber-reinforced masonry load-bearing walls , 2001 .

[14]  P. Lestuzzi,et al.  STATIC CYCLIC RESPONSE OF MASONRY WALLS RETROFITTED WITH FIBER-REINFORCED POLYMERS , 2007 .

[15]  Scott T. Smith,et al.  Experimental Investigation on FRP-to-Timber Bonded Interfaces , 2014 .

[17]  Muhammad Usman,et al.  Feasibility Study of MR Elastomer-based Base Isolation System , 2008 .

[18]  Cem Demir,et al.  FRP Retrofit of Low and Medium Strength Circular and Rectangular Reinforced Concrete Columns , 2008 .

[19]  Randolph Langenbach,et al.  From “Opus Craticium” to the “Chicago Frame”: Earthquake-Resistant Traditional Construction , 2007 .

[20]  R. Langenbach Don't Tear It Down! Preserving the Earthquake Resistant Vernacular Architecture of Kashmir , 2009 .

[21]  Naveed Ahmad,et al.  Shake Table Tests on Single-Story Dhajji Dewari Traditional Buildings , 2017 .

[22]  Randolph Langenbach Of Taq and Dhajji Dwari: the earthquake resistant mud and brick architecture of Kashmir , 1990 .

[23]  S. Rizwan,et al.  Eco-friendly self-compacting cement pastes incorporating wood waste as cement replacement: A feasibility study , 2018, Journal of Cleaner Production.

[24]  A. Hanif,et al.  Enhancing Lateral Load Performance of Traditional Timber Wall (Dhajji-Dewari) by Strengthening of joints , 2018, IOP Conference Series: Materials Science and Engineering.

[25]  Zeyu Lu,et al.  Mechanism of cement paste reinforced by graphene oxide/carbon nanotubes composites with enhanced mechanical properties , 2015 .