1. Ph.D. Candidate, Department of Civil Engineering, McMaster University, 1280 Main St. WEST, Hamilton, ON, L8S 4L7, malekim@mcmaster.ca
2. Associate Professor, Department of Civil and Environmental Engineering, The University of Western Ontario, damatty@uwo.ca
3. Adjunct Professor, Department of Civil Engineering, McMaster University, hamida@mcmaster.ca ⁴Professor, Department of Civil Engineering, McMaster University, drysdale@mcmaster.ca

ABSTRACT

This paper provides an evaluation of the capability of a layered finite element model using smeared crack approach to capture the behaviour of fully grouted fully reinforced masonry shear walls subject to in-plane loading. Tension stiffening, compression softening, as well as strength degradation of the grouted concrete block parallel to the crack direction are included in this model. The comparison between analytical and experimental results showed good agreement in prediction of pre- and post-peak response for different failure modes, although in shear dominated failure some differences were observed.

KEYWORDS: finite element, smeared crack, reinforced masonry, tension stiffening, orthotropic

8b-3

1. Director of Engineering, Brick SouthEast, Inc., Charlotte, NC, USA, BrickEric@aol.com
2. Professor of Architectural Engineering, North Carolina A & T State University, Greensboro, NC, USA, mcginley@ncat.edu

ABSTRACT

Conventional brick veneer in residential construction is typically supported by wood stud walls attached using 22 gauge corrugated wall ties and 8d nails. Previous research has demonstrated that the brick veneer offers significant resistance to in plane shear loads. As part of this phase of the research, analytical modeling of typical residential structures with and without brick veneer was performed using analytical and experimental results from previous investigations. The analytical modeling determined typical ranges for the lateral load resistance of the brick veneer.

KEYWORDS: brick, veneer, residential, modeling, lateral loads

8b-2

1. PhD researcher, Dept of Structural Design and Construction Technology, Eindhoven University of Technology, Vertigo 9.30, Postbus 513, 5600 MB Eindhoven, the Netherlands, b.m.ngandu@bwk.tue.nl
2. Assistant Professor, Dept of Structural Design and Construction Technology, Eindhoven University of Technology.
3. Professor, Dept of Structural Design and Construction Technology, Eindhoven University of Technology.

ABSTRACT

This paper describes and presents results of an experimental programme investigating the structural response of steel frames infilled with walls constructed of calcium silicate elements (CASIELs) in thin-layer mortar. This type of wall is increasingly employed in wall construction in Europe. Each of ten 3 m by 3 m steel infilled frames was subjected to an in-plane monotonic horizontal load at the roof beam level. The variables investigated were the presence of an initial gap below the roof beam, the frame-to-wall stiffness ratio and the influence of a top corner bearing wedge. Measurements included rigid body movements, gaps and slips at frame-wall interfaces as well as at selected joints, and strains at selected sites on the walls. Loaddeformation curves show a three stage response prior to cracking. In general, there is an initial stiff stage before a transition stage during which frame-wall separation occurs. This is followed by another stiff linear load-deflection primary stiffness range leading to diagonal tension cracking. When shear cracking along the bed joint below the topmost CASIEL layer occurs, the infilled frames more or less instantly recover their stiffness. An initial top gap results in large deflections during the transition phase and a reduced primary stiffness although it does not reduce the cracking load. Increasing the frame-to-wall stiffness ratio increases the primary stiffness and the diagonal cracking load. By using a bearing wedge at the top corners, the influence of the top gap is significantly reduced. This may be significant in developing a construction technique for industrial application of infilled frames. The global responses, together with the strain distributions derived from rosette measurements on the walls provide a data base for calibration of a finite element model.

KEYWORDS: infilled frames, CASIELs, thin layer mortar, stiffness, bearing wedge

8b-1

1. Vice President of Research and Development, National Concrete Masonry Association
2. Principal, Bradfield Consulting

ABSTRACT

Concrete masonry walls designed as security barriers are fully grouted concrete masonry assemblies. Typically, vertical grouted cells have steel reinforcement in every cell, and reinforced horizontal bond beams may also be specified. This type of construction is found in prisons, secure facilities or other areas where the integrity of the building envelope or wall partition is vital to securing an area. This paper reports on two phases of research into the impact performance of these types of concrete masonry walls. The testing protocol used was based on ASTM F 2322, Standard Test Methods for Physical Assault on Vertical Fixed Barriers for Detention and Correctional Facilities. Each wall was subjected to a simulated attack from a sledgehammer and a firefighter’s axe. The simulated attack was a series of impacts from a

pendulum test apparatus. Failure was considered to be damage to the wall assembly such that forcible egress can be achieved. Forcible egress was defined as an opening created in the wall assembly which allows a 5 inch x 8 inch x 8 inch (127 x 203 x 203 mm) rigid rectangular box to be passed through the wall with no more than 44.5 N (10 lb) of force.

KEYWORDS: concrete masonry, detention facility, impact test, physical security, security barrier

8a-3

1. Professor, Dept of Civil and Envr Engr, University of Tennessee, Knoxville, TN 37996-2010, rmbennett@utk.edu
2. Vice President, Engineering and Research, Brick Industry Association, Reston, VA 20191-1525, borchelt@bia.org
3. Manager Engineering Services, General Shale Products Corp., Johnson City, TN 37601, jbryja@generalshale.com
4. Executive Director, Southern Brick Institute, Conyers, Georgia 30013, bill@sbionline.org

ABSTRACT

Typical residential brick veneer wall construction consisting of brick veneer, oriented strandboard sheathing, wood studs, batt insulation, and gypsum wallboard was tested for the impact resistance to hurricane wind-blown debris. Tests were performed by impacting the wall with a 40 N (9 lb) 50 mm x 100 mm (2 in. x 4 in.) timber at various speeds. The Florida building code requires wall assemblies up to 9.1 m (30 ft) in height in high velocity hurricane zones to resist an impact from a 40 N (9 lb) 50 mm x 100 mm (2 in. x 4 in.) timber travelling at 55 km/hr (34 mph). ASTM E 1996 has an identical requirement for basic protection in high wind zones. ASTM E 1996 requires essential facilities to resist a 40 N (9 lb) 50 mm x 100 mm (2 in. x 4 in.) timber travelling at 88 km/hr (55 mph). In these tests, there was slight cracking of the veneer at a missile speed of 55 km/hr (34 mph). At 88 km/hr (55 mph), there was cracking of the veneer and a 10 mm (3/8 in.) penetration of the veneer. There was no damage to the sheathing or gypsum wallboard. When the missile was shot at 109 km/hr (68 mph), there was a 38 mm (1-1/2 in.) penetration of the missile, but again there was no damage to the sheathing or gypsum wallboard. A test at 127 km/hr (79 mph) on a wall panel with only half the ties resulted in a 6 mm (1/4 in.) penetration of the brick veneer and failure of the timber missile. These tests show that conventional brick veneer construction clearly exceeds the Florida Building Code and ASTM E 1996 requirements for impact resistance of hurricane debris.

KEYWORDS: brick veneer, hurricane, missile, impact resistance, windborne debris

8a-2

1. Senior Lecturer, Dept of Civil Engineering, National Institute of Technology, Hamirpur, (HP), India – 177 005, pkumar@recham.ernet.in  
2. Professor, Dept of Civil Engineering, Indian Institute of Technology, Roorkee, (UA), India – 247 667, nmbcefce@iitr.ernet.in

ABSTRACT

Masonry arch bridges exist in large numbers in the transport network of many countries. The majority of these bridges were built/designed for carrying loads far less than they are carrying today. Different methods of assessment of these bridges exist. The Finite Element Method (FEM) is extensively used these days in all fields of civil engineering. The use of the FEM in analyzing complex structures like masonry arch bridges has been found to provide good assessments. A two-dimensional Finite Element analysis of masonry arch bridges ignores the transverse effects but the behaviour in the span direction can be effectively modeled. In view of this a masonry arch bridge has been analyzed using a two-dimensional non-linear finite element method computer program that has been developed. A three dimensional nonlinear finite element analysis of the same bridge has been carried out using commercially available general-purpose finite element analysis software, using the inbuilt material models and failure functions. Comparison of the two sets of results indicates the suitability of the two-dimensional analysis for the purpose of load rating. The displacements along the span obtained through a shift in the position of the load in the transverse direction do not significantly vary the magnitudes of the maximum displacements at different locations along the span. A significant variation in the transverse direction was indeed observed. The variation in the transverse direction can seriously affect the carrying capacity of the bridge, if the load is placed on the edge, due to cracking and separation of spandrel walls. The displacements observed under service loads are a lot less than those under collapse loads. Hence for overall assessment, a three-dimensional finite element analysis cannot be ignored, but for a quick load rating a two dimensional finite element analysis is sufficient. The details of the investigation are reported here in the paper.

KEYWORDS: bridge, load carrying capacity, non-linear FEA

8a-1

NSERC Post-doctoral Fellow, Center for Infrastructure Engineering Studies, University of Missouri-Rolla 223 Engineering Research Lab., Rolla, Missouri 65409-0710, yasser.korany@gmail.com

ABSTRACT

In spite of the rapid increase in the application of Fibre Reinforced Polymers (FRPs) to masonry structures, theory and rigorous analysis seem to lag behind. Most of the research work focused on the proof of the effectiveness of the application. There is a need for developing rational design approaches to enable designers and architects to utilize FRPs to their full potential. There are presently no codes of practice available for the design of neither FRP-reinforced or FRPstrengthened masonry structures. There are, however, a limited number of documents that provide design guidelines on reinforcing and strengthening concrete structures using FRPs.

In this paper, an approach for the design of FRP-reinforced masonry is presented. The approach is based on the accumulated body of knowledge on the use of FRPs to reinforce masonry and concrete structures. The proposed design approach is discussed in the context of the provisions of the Canadian Standards CSA S304.1-04 Design of Masonry Structures and CSA S806-02 Design and Construction of Building Components with Fibre Reinforced Polymers. The principles of the limit states design method are followed.

KEYWORDS: Fibre Reinforced Polymers, Reinforced Masonry, Design, Analysis

7c-5

1. Professor, Dept. of Architectural Engineering, North Carolina A & T State University. Greensboro, NC 27411. Email: mcginley@ncat.edu.
2. MSc student, Department of Civil, Architectural, Agricultural and Environmental Engineering, North Carolina A & T State University. Greensboro, NC 27411.
3. Associate Professor, Civil Engineering Department, University of North Carolina at Charlotte, Charlotte, NC 28223. E-mail: jgergely@uncc.edu. Phone: 704-687-4166, Fax: 704-687-6953.
4. PhD student, Civil Engineering Department, University of North Carolina at Charlotte, Charlotte, NC 28223. E-mail: pbfoster@uncc.edu. Fax: 704-687-6953.
5. Professor and Chair, Civil Engineering Department, University of North Carolina at Charlotte, Charlotte, NC E-mail: dyoung@uncc.edu. Phone: 704-687-4175, Fax: 704-687-6953

ABSTRACT

As part of a combined effort at North Carolina A & T State University and The University of North Carolina at Charlotte, an investigation into the repair of unreinforced masonry structures is underway. The objective of this research is to develop a methodology for the design of fibre reinforced plastic (FRP) repair/strengthening systems for masonry shear walls. The prime focus of the investigation involves evaluating the use of small assembly tests to predict the behaviour of large scale structures. The small assembly tests were conducted on both brick and block masonry prisms and these prisms were subjected to either tension, compression, or shear loading to failure. The behaviour of the small tests were used to predict the performance of two large scale test specimens that were repaired/strengthened by FRP systems and the results were compared. Reasonable agreement was obtained during this comparison but further development is needed to improve the modeling procedures.

KEYWORDS: strengthening, FRP, design

7c-4

1. NSERC Post-doctoral Fellow, Center for Infrastructure Engineering Studies, University of Missouri-Rolla 223 Engineering Research Lab., Rolla, Missouri 65409-0710, yasser.korany@gmail.com
2. Professor & Martini, Mascarin and George Chair in Masonry Design Director, Centre for Effective Design of Structures, Department of Civil Engineering, McMaster University, 1280 Main St. W., Hamilton, ON L8S 4L7, drysdale@mcmaster.ca

ABSTRACT

Unobtrusive FRP rehabilitation techniques were developed to enhance the out-of-plane flexural resistance of masonry wall panels by increasing their ability to absorb energy. In these techniques, unbonded and intermittently bonded FRP reinforcement were used to produce higher rotations and, consequently, large displacements. Experimental and analytical investigations were conducted to evaluate the effectiveness of the developed FRP rehabilitation techniques. Without a design approach available for practitioners, the full potential of these techniques would be hard to realize.

In this paper, a simplified design methodology for calculating the capacity of this type of FRPreinforced masonry wall panel under out-of-plane pressure is described. The proposed method is based on an analytical model that was developed to predict the post-cracking lateral pressuredisplacement response under biaxial bending. The conservation of energy principle is applied to determine the capacity whereas displacement is calculated from rotations employing rigid body mechanics. The resulting wall sub-panels, subsequent to a fully developed crack pattern, are considered to behave as rigid segments that rotate around crack lines. The applicability of the design method is demonstrated by a numerical example.

KEYWORDS: wall panels, out-of-plane resistance, fibre reinforced polymers, unbonded reinforcement, intermittently bonded reinforcement, rigid-body mechanics

7c-3

1. Professor, McMaster University Centre for Effective Design of Structures, Department of Civil Engineering, Hamilton, Ontario, L8S 4L7 Canada, hamida@mcmaster.ca
2. Research Associate, McMaster University Centre for Effective Design of Structures, Department of Civil Engineering, Hamilton, Ontario, L8S 4L7 Canada, eldak@mcmaster.ca
3. Senior Engineer, Bechtel Power Corporation, Frederick, Maryland, 21703, USA, hakam@bechtel.com
4. Professor, Civil, Architectural and Environmental Engineering Department, Drexel University, Philadelphia, PA, 19104, USA, elgaaly@drexel.edu

ABSTRACT

An experimental investigation was conducted to study the behaviour of unreinforced masonry (URM) walls retrofitted with composite laminates. Five masonry-infilled steel frames were tested with and without retrofit. The composite laminates increased the stiffness and strength and enhanced the post peak behaviour by stabilizing the masonry walls and preventing their out-ofplane spalling. Tests reported in this paper demonstrate the efficiency of FRP laminates in improving the capacity of URM containing the hazardous URM damage, preventing catastrophic failure and maintaining the wall integrity even after significant structural damage.

KEYWORDS: composite masonry, concrete masonry, fibre reinforced plastics, infilled frames, retrofitting, seismic hazard

7c-2