The effect of mortar grade on the out-of-plane behaviour of low-strength masonry wall strengthened with welded wire mesh

Brick masonry is the principal part of the construction industry. This paper presents the result of the expanded wire mesh embedded into the masonry wall panel; expanded mesh (EM) is the inexpensive locally available material on the market. Through the experimental study, the primary affecting parameters recognized, and the methodology of the embedment details established, the preliminary survey was conducted as per the guidelines are given in the ASTM E518. Totally three numbers of control specimen and three numbers of EM embedded specimen are cast, and compressive strength test of masonry prism also evaluated to identify the crack propagation path. The test results turned out to be highly promising, out of plane damage was less in the EM embedded specimen also it was designated the cracks are reduced.

Download Full-text

Experimental Evaluation of Lightweight AAC Masonry Wall Prisms with Ferrocement Layers in Compression and Flexure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.166-169.1730 ◽

2012 ◽

Vol 166-169 ◽

pp. 1730-1735 ◽

Cited By ~ 1

Author(s):

Mohamed Abdel-Mooty ◽

Ahmed Hendam ◽

Ezzat Fahmy ◽

Mohamed Abou Zeid ◽

Medhat Haroun

Keyword(s):

Masonry Wall ◽

Wire Mesh ◽

Experimental Program ◽

Design Parameters ◽

Shear Connectors ◽

Mortar Strength ◽

Wall Strength ◽

Out Of Plane ◽

Strength And Stiffness ◽

Strengthening Technique

An experimental program is designed to evaluate the performance of lightweight autoclaved aerated concrete masonry wall strengthened using ferrocement layers, in a sandwich structure, under in-plane compression and out-of-plane bending. The 25 mm thick ferrocement mortar is reinforced with steel welded wire mesh of 1 mm diameters at 15 mm spacing. Different types of shear connectors are used to evaluate their effect on failure loads. The effect of different design parameters on the wall strength are considered including wall thickness, mortar strength, and type and distribution of shear connectors. A total of 20 prisms are tested in compression and 5 prisms are tested under bending. The proposed ferrocement strengthening technique is easy to apply on existing wall system and results in significant strength and stiffness enhancement of the tested wall specimens.

Download Full-text

Mechanical Properties of Various Models of Interlocking Concrete Blocks under In-Plane and Out-of-Plane Loads

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.881.149 ◽

2021 ◽

Vol 881 ◽

pp. 149-156

Author(s):

Mochamad Teguh ◽

Novi Rahmayanti ◽

Zakki Rizal

Keyword(s):

Mechanical Properties ◽

Building Material ◽

Experimental Tests ◽

Concrete Block ◽

Masonry Wall ◽

Masonry Walls ◽

Plane Shear ◽

Out Of Plane ◽

Concrete Blocks ◽

Local Materials

Building material innovations in various interlocking concrete block masonry from local materials to withstand lateral earthquake forces is an exciting issue in masonry wall research. The block hook has an advantage in the interlocking system's invention to withstand loads in the in-plane and out-of-plane orientations commonly required by the masonry walls against earthquake forces. Reviews of the investigation of in-plane and out-of-plane masonry walls have rarely been found in previous studies. In this paper, the results of a series of experimental tests with different interlocking models in resisting the simultaneous in-plane shear and out-of-plane bending actions on concrete blocks are presented. This paper presents a research investigation of various interlocking concrete blocks' mechanical properties with different hook thicknesses. Discussion of the trends mentioned above and their implications towards interlocking concrete block mechanical properties is provided.

Download Full-text

Wire Ropes and CFRP Strips to Provide Masonry Walls with Out-Of-Plane Strengthening

Materials ◽

10.3390/ma12172712 ◽

2019 ◽

Vol 12 (17) ◽

pp. 2712

Author(s):

Elena Ferretti

Keyword(s):

Steel Wire ◽

Three Dimensional ◽

Maximum Load ◽

Masonry Wall ◽

Masonry Walls ◽

Wire Ropes ◽

Out Of Plane ◽

Beam Mechanism ◽

Combined Technique ◽

The Ideal

The present paper deals with an improvement of the strengthening technique consisting in the combined use of straps—made of stainless steel ribbons—and CFRP (Carbon Fiber Reinforced Polymer) strips, to increase the out-of-plane ultimate load of masonry walls. The straps of both the previous and the new combined technique pass from one face to the opposite face of the masonry wall through some holes made along the thickness, giving rise to a three-dimensional net of loop-shaped straps, closed on themselves. The new technique replaces the stainless steel ribbons with steel wire ropes, which form closed loops around the masonry units and the CFRP strips as in the previous technique. A turnbuckle for each steel wire rope allows the closure of the loops and provides the desired pre-tension to the straps. The mechanical coupling—given by the frictional forces—between the straps and the CFRP strips on the two faces of the masonry wall gives rise to an I-beam behavior that forces the CFRP strips to resist the load as if they were the two flanges of the same I-beam. Even the previous combined technique exploits the ideal I-beam mechanism, but the greater stiffness of the steel wire ropes compared to the stiffness of the steel ribbons makes the constraint between the facing CFRP strips stiffer. This gives the reinforced structural element a greater stiffness and delamination load. In particular, the experimental results show that the maximum load achievable with the second combined technique is much greater than the maximum load provided by the CFRP strips. Even the ultimate displacement turns out to be increased, allowing us to state that the second combined technique improves both strength and ductility. Since the CFRP strips of the combined technique run along the vertical direction of the wall, the ideal I-beam mechanism is particularly useful to counteract the hammering action provided by the floors on the perimeter walls, during an earthquake. Lastly, when the building suffers heavy structural damage due to a strong earthquake, the box-type behavior offered by the three-dimensional net of straps prevents the building from collapsing, acting as a device for safeguarding life.

Download Full-text

Applied Element Method Simulation of Fiber Reinforced Polymer and Polypropylene Composite Retrofitted Masonry Walls

Advances in Structural Engineering ◽

10.1260/1369-4332.17.11.1567 ◽

2014 ◽

Vol 17 (11) ◽

pp. 1567-1583 ◽

Cited By ~ 5

Author(s):

Saleem M. Umair ◽

Muneyoshi Numada ◽

Kimiro Meguro

Keyword(s):

Numerical Model ◽

Research Work ◽

Masonry Wall ◽

Fiber Reinforced Polymer ◽

Bending Test ◽

Fiber Reinforced ◽

Reinforced Polymer ◽

Out Of Plane ◽

Applied Element Method ◽

Element Method

In current research work, an attempt is made to simulate the behavior of a newly proposed composite material using 3-D Applied Element Method (AEM). Fiber Reinforced Polymer (FRP) being a strong material provides a significant increase in shear strength. Polypropylene band (PP-band) not only holds the masonry wall system into a single unit but also provides a fairly high deformation capacity at a very low cost of retrofitting. A composite of FRP and PP-band is proposed and applied on the surface of masonry wall. Verification of the proposed numerical model is achieved by conducting experiments on twelve masonry wallets. Out of twelve, six masonry wallets were tested in out of plane bending test and six were tested under in-plane forces in the form of diagonal compression test. Same wallet retrofitting scheme was selected for in-plane and out of plane experiments and all of them were analyzed using proposed 3-D AEM numerical simulation tool. Proposed numerical model has served satisfactory and has shown a fairly good agreement with experimental results which encourages the use of 3D-AEM to numerically simulate the behavior of non-retrofitted and retrofitted masonry wallets.

Download Full-text

Pre-Tensioned Basalt Fibers Ropes Stitching for Masonry Strengthening against Vertical Bending: A First Experimental Insight

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.747.119 ◽

2017 ◽

Vol 747 ◽

pp. 119-127 ◽

Cited By ~ 1

Author(s):

Francesco Monni ◽

Enrico Quagliarini ◽

Stefano Lenci

Keyword(s):

Seismic Behavior ◽

Basalt Fiber ◽

Masonry Wall ◽

Masonry Walls ◽

Architectural Heritage ◽

Experimental Campaign ◽

Out Of Plane ◽

Most Significant Change ◽

Synthetic Adhesives ◽

The Common

This paper presents the results of an experimental campaign aimed at improving the innovative technique of continuos basalt fiber (BF) stitching in order to repair the masonry panels damaged by seismic events or to enhance the seismic behavior of unreinforced masonry walls. The masonry panels were tested under out-of-plane actions, one of the common way of failure for masonry walls during an earthquake. The most significant change introduced respect to the system already tested in previous studies, is the presence of pre-tensioned elements and mechanical anchorage of the BF ropes, always with the end of proposing a dry retrofitting system. The results indicate the effectiveness of this, increasing the performance of masonry wall specimens under out-of-plane actions respect to the damaged and unreinforced conditions. Besides, this technique potentially appears fully sustainable, because it is cheap, compatible, reversible, fire, and chemical resistant, it improves but not replaces original materials and, finally, it does not substantially use synthetic adhesives. All these reasons make this novel application of BF ropes fully sustainable and specialized to architectural heritage restoration.

Download Full-text

Discrete element modelling of the in-plane and out-of-plane behaviour of dry-joint masonry wall constructions

Engineering Structures ◽

10.1016/j.engstruct.2017.01.020 ◽

2017 ◽

Vol 136 ◽

pp. 277-294 ◽

Cited By ~ 65

Author(s):

T.T. Bui ◽

A. Limam ◽

V. Sarhosis ◽

M. Hjiaj

Keyword(s):

Discrete Element ◽

Masonry Wall ◽

Discrete Element Modelling ◽

Element Modelling ◽

Out Of Plane

Download Full-text

An Assessment of Brick Masonry Strengthening Practice by Special Methods

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.c4242.098319 ◽

2019 ◽

Vol 8 (3) ◽

pp. 1529-1533

Keyword(s):

Conventional Method ◽

Cementitious Materials ◽

Masonry Wall ◽

Brick Masonry ◽

Wire Mesh ◽

Suitable Method ◽

Structural Performance ◽

Masonry Structures ◽

Excellent Performance ◽

Metal Mesh

This study aims to identify the best suitable method to enhance strength and the structural performance of masonry. There are different techniques available to strengthen the existing and new masonry structures. This paper deals the metal/mesh embedment in the masonry wall, strengthening by added different polymers and textile strips, masonry grout, engineered cementitious materials (ECC) and interlocking masonry method. The comparison of different unique masonry strengthening methods helps us to provide a better suggestion for construction issues. In contrast to the conventional method, welded wire mesh gives better results than all other ways. Also, embedment of TRM, ECC, FRP, GFRP, CFRP, and interlocking holds an excellent performance in some other aspects.

Download Full-text

Experimental Study on Out-of-Plane Seismic Performance of New Type Masonry System

Applied Sciences ◽

10.3390/app112411736 ◽

2021 ◽

Vol 11 (24) ◽

pp. 11736

Author(s):

Ho Choi ◽

Kang-Seok Lee

Keyword(s):

Seismic Performance ◽

Masonry Wall ◽

Shaking Table ◽

Shaking Table Tests ◽

Preliminary Calculation ◽

Four Point Bending ◽

Out Of Plane ◽

New Type ◽

Block Wall ◽

Joint Mortar

The authors developed two types of block systems, consisting only of main and key blocks, without joint mortar, to improve the in- and out-of-plane seismic performances and enhance the workability. Two types of block systems have different key block shapes. One is the peanuts shape, and the other is the H shape. The proposed block systems have a half-height difference between the main and key blocks, to significantly improve seismic performance in in- and out-of-plane directions, compared to typical masonry wall with joint mortar. In this study, in order to evaluate the out-of-plane seismic performance of the proposed block systems, two types of block walls are experimentally investigated, including the typical block wall. Firstly, the shaking table tests are carried out to investigate the fundamental out-of-plane behaviors of three specimens. Next, four-point bending tests are planned to evaluate the out-of-plane seismic performance, since all specimens do not occur the out-of-plane collapse in the shaking table tests from the preliminary calculation. In this paper, the development of predominant period, profiles of acceleration and displacement, and maximum tensile strength of each specimen are discussed in detail. As a result, the maximum loads of the proposed block walls were about three to four times that of the typical block wall. This result means that the proposed block system has significantly improved seismic performance in the out-of-plane direction.

Download Full-text