CMDC https://www.canadamasonrydesigncentre.com Supporting the Masonry Design Community Thu, 29 Feb 2024 20:50:03 +0000 en-US hourly 1 https://wordpress.org/?v=6.4.3 https://www.canadamasonrydesigncentre.com/wp-content/uploads/2023/09/cropped-android-chrome-512x512-1-32x32.png CMDC https://www.canadamasonrydesigncentre.com 32 32 University of Saskatchewan https://www.canadamasonrydesigncentre.com/research/university-of-saskatchewan/ Mon, 13 Nov 2023 15:34:28 +0000 https://www.canadamasonrydesigncentre.com/?p=13027

CMDC has worked in collaboration with Lisa Feldman, Bruce Sparling, Leon Wegner, and Mohamed Boulfiza from the University of Saskatchewan.

Supporting Innovation through Research Partnerships

Work has been conducted on the following projects:

Masonry Unit Geometry

Project Summary:

Hollow concrete masonry units manufactured according to the requirements of CSA A165.1, and installed according to common practices and applicable codes and standards in Canada, have a long history of acceptable performance. However, until recently, little effort had been focused to optimizing the geometric properties of the masonry units to balance performance with other aspects of production and installation (e.g., decreasing the weight of the units, facilitating grout flow within grouted masonry, etc.).

The goal of this study is to examine the effect of variations in the geometric properties of hollow concrete masonry units which have recently been introduced in the U.S. The project includes testing of grouted and ungrouted masonry prisms, and larger masonry assemblages, constructed from units with reduced web thickness and reduced web height.

Recent NAMC Articles:

Heide, M., and Feldman, L.R. (2023, June). “Influence of Web Geometry on Concrete Masonry Walls Subject to Out-of-Plane Loading.” In Proceedings of the Fourteenth North American Masonry Conference. Paper presented at the 14th North American Masonry Conference, Omaha, Nebraska (pp. 89-98). Longmont, CO: The Masonry Society.

Recent Technical Publications:

Chhetri, Nitesh, and Lisa R. Feldman.  “Impact of Concrete Masonry Unit Geometry on Masonry Assemblage Strength,” Canadian Journal of Civil Engineering, published online as a first-look article, (2023).

Select Theses and HQP:

Nitesh Chhetri: https://harvest.usask.ca/handle/10388/14185

Development of Bond for Masonry Reinforcement

Project Summary:

Bond between reinforcing bars and the cementitious materials used in conventional concrete block masonry is required for the assemblage to perform satisfactorily. Dr. Feldman’s research on the bond of masonry reinforcement allows designers to reduce conservatism in design while maintaining a high degree of safety. A lack of recent research on this topic has led discrepancies between Canadian and USA standards, and possible over-conservatism, when calculating the required development and splice lengths.

This project applies lessons learned in the reinforced concrete industry to reinforced masonry construction through a comprehensive testing and analysis programme.

Select Journal Articles:

Kisin, Aleksandar, and Lisa R. Feldman. “Corrective Measures for Noncontact Splices in Concrete Block Masonry.” ACI Structural Journal 112, no. 4 (2015).

Kelln, Roanne D., and Lisa R. Feldman. “Bar size factors for lap splices in block walls subjected to flexure.” Canadian Journal of Civil Engineering 42, no. 8 (2015): 521-529.

Resistance of Masonry Assemblages

Project Summary:

A recent study of Canadian and U.S.A. masonry design standards has revealed many differences in the approach and requirements including the engineering design of beams and slender walls, and the determination of compressive strength. For example, in Canada, the design of masonry beams is made challenging because of the lower strength that is allowed to be attributed to masonry subjected to horizontal compression (compression across the vertical head joints).

The testing series includes comparing the performance of identically reinforced beams with the masonry units being laid horizontally or stacked. ASTM and CSA compression test methods for masonry assemblages, including the dimensions of the test specimens, are also compared.

This project is part of a larger effort to harmonize masonry design standards between Canada and the U.S.A to help save costs and promote trade on both sides of the border.

Select Journal Articles:

Vachon, Thomas C.J., and Lisa R. Feldman.  “A Reassessment of the CSA S304 Chi-Factor for Design of Reinforced Concrete Masonry Members: Large-Scale Experimental Investigation,” Canadian Journal of Civil Engineering  50, no. 7 (2023): 621-632.

Select Theses and HQP:

Ting Hin (Gordon) Chui: https://harvest.usask.ca/handle/10388/14055

Thomas Vachon: https://harvest.usask.ca/handle/10388/14334

Cold Weather Masonry Construction

Project Summary:

The Canadian climate poses special challenges for masonry construction during the winter months. Current standards require masonry works to be maintained at a temperature above freezing for a minimum of 48 hours after construction to allow initial curing of the mortar. In winter, ensuring an adequate ambient temperature is maintained (heating of construction enclosure) during this initial curing time poses a logistical challenge, and increases energy usage (and GHG emissions) and construction costs.

The current study explores the conditions under which modern antifreeze additives may be used with masonry mortars to decrease the required heating time of masonry construction works during the winter months in cold climate regions.

Select Journal Articles:

Saha, Ouafi, Moh Boulfiza, and Leon D. Wegner.  “Behavior of Masonry Mortar Containing a Non-Harmful Antifreeze Admixture.”  TMS Journal 37, no. 1 (2019): 1 – 10.

Select Theses and HQP: :

Ouafi Saha: https://harvest.usask.ca/handle/10388/12384

Unbonded reinforcement

 

Project Summary:

Reinforcing masonry assemblages is typically achieved by introducing bars in the hollow cells of concrete masonry units and bonding that reinforcement to the masonry using masonry grout. However, many of the benefits of a reinforced masonry wall can be achieved without bonding through a grouted connection if the reinforcement is prestressed and connected at the top and bottom of the wall. Unbonded prestressed reinforcement is regularly used in reinforced concrete construction (e.g., for long bridge girders), but is seldom seen in masonry construction.

This research project explored the potential of using lightly prestressed masonry walls with unbonded reinforcement to reduce the weight and construction cost of interior reinforced masonry partition walls.

Select Journal Articles:

Miranda, Henry P., Lisa R. Feldman, and Bruce F. Sparling. “Proof of concept investigation of unbonded reinforcement in concrete block masonry.” Canadian Journal of Civil Engineering 45, no. 11 (2018): 936-946.

Select Theses and HQP:

Miranda Henry: https://harvest.usask.ca/handle/10388/11981

]]> Concordia University https://www.canadamasonrydesigncentre.com/research/concordia-university/ Mon, 13 Nov 2023 14:33:13 +0000 https://www.canadamasonrydesigncentre.com/?p=13020

CMDC has worked in collaboration with Khaled Galal from Concordia University

Supporting Innovation through Research Partnerships

Work has been conducted on the following projects:

Shear Walls with Boundary Elements

Project Summary:

Reinforced masonry shear walls are effective structural elements to resist lateral loads on buildings including wind loads and seismic loads. This research project led by Dr. Galal focuses on testing of reinforced masonry shear wall configurations to develop more economical methods of construction for buildings that are required to resist moderate earthquake loads. Focusing on the detailing of reinforcement, strategies to enhance the performance of current masonry construction methods are being developed.

This project includes testing masonry materials, of half-scale reinforced masonry shear walls (including rectangular walls, walls with boundary elements, and even partially-grouted walls), and computer modeling and analysis of the walls and of whole buildings with masonry shear walls.

In addition to developing new strategies for design and improving the seismic safety of buildings, the project also contributes to better understanding the characteristics of masonry materials in general.

Select Journal Articles:

AbdelRahman, Belal, and Khaled Galal. “Experimental investigation of axial compressive behavior of square and rectangular confined concrete-masonry structural wall boundary elements.” Engineering Structures 243 (2021): 112584.

Albutainy, Mohammed, and Khaled Galal. “Experimental investigation of reinforced concrete masonry shear walls with C-shaped masonry units boundary elements.” In Structures, vol. 34, pp. 3667-3683. Elsevier, 2021.

Hosseinzadeh, Shadman, and Khaled Galal. “Probabilistic seismic resilience quantification of a reinforced masonry shear wall system with boundary elements under bi-directional horizontal excitations.” Engineering Structures 247 (2021): 113023.

Aly, Nader, and Khaled Galal. “In-plane cyclic response of high-rise reinforced concrete masonry structural walls with boundary elements.” Engineering Structures 219 (2020): 110771.

Aly, Nader, and Khaled Galal. “Experimental investigation of axial load and detailing effects on the inelastic response of reinforced-concrete masonry structural walls with boundary elements.” Journal of Structural Engineering 146, no. 12 (2020): 04020259.

Hosseinzadeh, Shadman, and Khaled Galal. “System-level seismic resilience assessment of reinforced masonry shear wall buildings with masonry boundary elements.” In Structures, vol. 26, pp. 686-702. Elsevier, 2020.

Aly, Nader, and Khaled Galal. “Seismic performance and height limits of ductile reinforced masonry shear wall buildings with boundary elements.” Engineering Structures 190 (2019): 171-188.

Hamzeh, Layane, Ahmed Ashour, and Khaled Galal. “Development of fragility curves for reinforced-masonry structural walls with boundary elements.” Journal of Performance of Constructed Facilities 32, no. 4 (2018): 04018034.

Obaidat, Ala’T., Ahmed Ashour, and Khaled Galal. “Stress-strain behavior of C-shaped confined concrete masonry boundary elements of reinforced masonry shear walls.” Journal of Structural Engineering 144, no. 8 (2018): 04018119.

El Ezz, Ahmad Abo, and Khaled Galal. “Compression behavior of confined concrete masonry boundary elements.” Engineering Structures 132 (2017): 562-575.

Reinforced Masonry Shear Walls

Project Summary:

Reinforced masonry shear walls are effective structural elements to resist lateral loads on buildings including wind loads and seismic loads. This research project led by Dr. Galal focuses on testing of reinforced masonry shear wall configurations to develop more economical methods of construction for buildings that are required to resist moderate earthquake loads. Focusing on the detailing of reinforcement, strategies to enhance the performance of current masonry construction methods are being developed. This project includes testing masonry materials, of half-scale reinforced masonry shear walls (including rectangular walls, walls with boundary elements, and even partially-grouted walls), and computer modeling and analysis of the walls and of whole buildings with masonry shear walls. In addition to developing new strategies for design and improving the seismic safety of buildings, the project also contributes to better understanding the characteristics of masonry materials in general.

Select Journal Articles:

Elmeligy, Omar, Nader Aly, and Khaled Galal. “Sensitivity analysis of the numerical simulations of partially grouted reinforced masonry shear walls.” Engineering Structures 245 (2021): 112876.

Aly, Nader, and Khaled Galal. “Effect of ductile shear wall ratio and cross-section configuration on seismic behavior of reinforced concrete masonry shear wall buildings.” Journal of Structural Engineering 146, no. 4 (2020): 04020020.

ElDin, Hany M. Seif, Ahmed Ashour, and Khaled Galal. “Seismic performance parameters of fully grouted reinforced masonry squat shear walls.” Engineering Structures 187 (2019): 518-527.

ElDin, Hany M. Seif, Nader Aly, and Khaled Galal. “In-plane shear strength equation for fully grouted reinforced masonry shear walls.” Engineering Structures 190 (2019): 319-332.

Recent NAMC Articles:

Aly N. and Galal K. (2019, June). “Influence of Ductile Shear Wall Ratio on the Seismic Performance of Reinforced Concrete Masonry Shear Wall Buildings.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1462–1474). Longmont, CO: The Masonry Society.

Masonry Prisms

Project Summary:

Masonry prisms are essential structural elements utilized in construction to evaluate the compressive strength and other mechanical properties of masonry materials. These test specimens, constructed by bonding masonry units with mortar, replicate real-world construction conditions, ensuring the relevance of the obtained data. CSA S304 provides guidelines for the preparation, testing, and analysis of these prisms. The testing process involves subjecting the prisms to axial loads to determine compressive strength and may include shear strength tests to assess resistance to lateral forces.

In this research, masonry prisms are used to investigate the impact of fibre reinforced grout, and boundary elements built using C-shaped blocks. The resulting data contributes to the development of construction guidelines and safety standards, informing the design of durable and secure masonry structures in real-world applications. In essence, masonry prisms play a crucial role in advancing our understanding of masonry behavior and promoting the reliability of construction practices.

Recent Journal Articles:

Gouda, Omar, Ahmed Hassanein, Tarik Youssef, and Khaled Galal. “Stress-strain behaviour of masonry prisms constructed with glass fibre-reinforced grout.” Construction and Building Materials 267 (2021): 120984.

AbdelRahman, Belal, and Khaled Galal. “Influence of pre-wetting, non-shrink grout, and scaling on the compressive strength of grouted concrete masonry prisms.” Construction and Building Materials 241 (2020): 117985.

Masonry Columns Strengthened by FRP

Project Summary:

Research on masonry columns strengthened by Fiber-Reinforced Polymer (FRP) composites aims to enhance the load-carrying capacity and ductility of existing structures. This involves applying high-strength fibers embedded in a polymer matrix externally to masonry columns, particularly beneficial for retrofitting older structures or improving original design capacities. The test matrix was designed to measure the effect of the presence of longitudinal steel reinforcement in the columns on the compressive strength of FRP-confined concrete masonry.

As the demand for sustainable retrofitting solutions increases, research in this area plays a pivotal role in advancing innovative techniques for strengthening masonry columns, ensuring resilience in diverse environmental and loading conditions.

Recent NAMC Articles:

Alotaibi K. and Galal K. (2019, June). “Compressive Strength of FRP-Confined Concrete Masonry With and Without Longitudinal Steel Reinforcement.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1523–1529). Longmont, CO: The Masonry Society

Select Journal Articles:

El-Sokkary, Hossam, and Khaled Galal. “Performance of eccentrically loaded reinforced-concrete masonry columns strengthened using FRP wraps.” Journal of Composites for Construction 23, no. 5 (2019): 04019032.

Alotaibi, Khalid Saqer, and Khaled Galal. “Experimental study of CFRP-confined reinforced concrete masonry columns tested under concentric and eccentric loading.” Composites Part B: Engineering 155 (2018): 257-271.

Alotaibi, Khalid Saqer, and Khaled Galal. “Axial compressive behavior of grouted concrete block masonry columns confined by CFRP jackets.” Composites Part B: Engineering 114 (2017): 467-479

Select Theses and HQP: :

Khalid Alotaibi: https://spectrum.library.concordia.ca/id/eprint/984232/

]]> Carleton University https://www.canadamasonrydesigncentre.com/research/carleton-university/ Mon, 13 Nov 2023 14:16:22 +0000 https://www.canadamasonrydesigncentre.com/?p=13017

CMDC has worked in collaboration with Ehab Zalok and Edward G. Sherwood from Carleton University.

Supporting Innovation through Research Partnerships

Work has been conducted on the following projects:

Fire Resistance of Masonry

Project Summary:

Masonry materials have been relied upon extensively over the last century as an effective form of fire barrier in buildings. The goals of this research project are to: develop the next-generation of masonry fire performance standards, improve fire-rated masonry assemblage design and construction, optimize masonry unit manufacturing for fire resistance and facilitate robust post-disaster assessment of fire damaged masonry.

A series of experimental tests will be conducted on the fire performance of full sized non-loadbearing (partition) masonry walls, and small-scale assemblages to quantify the effects of a variety of parameters on heat and mass transfer, fire endurance, and mechanical behavior and residual strength of typical and prototype concrete blocks and masonry assemblages.

Recent NAMC Articles:

Pope H. and Zalok E. (2019, June). “The Effect of Fire Temperatures on the Mechanical Performance of Concrete Masonry Materials.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 252–264). Longmont, CO: The Masonry Society.

Shear Design of Masonry

Project Summary:

Unlike flexural failures, shear failures in masonry are brittle and sudden. When they occur, they do so with little or no warning, and absorb little energy. Furthermore, they are less predictable than flexural failures due to considerably more complex failure mechanisms. While accurate flexural design provisions have been based on the rational assumption that plane sections remain plane, shear design procedures have traditionally relied upon empirical, restricted equations. As such, the search continues for shear design procedures that are as accurate as flexural procedures, based on equally rational assumptions.

Select Journal Articles:

Sarhat, Salah, and Edward Sherwood. “Shear strength of GFRP-reinforced concrete masonry beams.” In Masonry 2018. ASTM International, 2018.

Sarhat, Salah R., and Edward G. Sherwood. “Does the size effect exist in reinforced masonry?.” ACI Special Publication 328 (2018): 5-1.

Compressive Strength of Concrete Block Masonry

Project Summary:

Accurately predicting the compression strength of masonry is very important in design of masonry structures, as it is often the basis of designs. However, determining the compression strength of masonry is not a simple task. This is because each material (hollow concrete masonry blocks, mortar, and possibly grout) has different material properties and responds in a different non-linear manner when subjected to compression.

Masonry design codes generally provide two methods to determine compression strength: masonry prism testing or unit strength. The first method, masonry prism testing, consists of constructing three to five masonry prisms with site representative materials; testing the prisms under compressive loading; and correcting the average compression strength determined from testing by a factor that accounts for the height to thickness ratio of the tested prisms. This method has certain practical limitations in terms of the complexities of transporting samples and the capacity and size of available testing machines. Furthermore, there are disagreements on the values of the height to thickness correction factors as each international code provides different values. The second method, known as the unit strength method, involves testing individual samples of masonry component materials. In this approach, the compressive strength of masonry is estimated by either an equation or through tabulated values based on block strength, mortar type or strength, and possibly grout strength.

]]> McMaster University https://www.canadamasonrydesigncentre.com/research/mcmaster-university/ Fri, 10 Nov 2023 20:54:54 +0000 https://www.canadamasonrydesigncentre.com/?p=13006

CMDC has worked in collaboration with Wael El- Dakhakhni, Mohamed Ezzeldin, and Lydell Wiebe from McMaster University.

Supporting Innovation through Research Partnerships

Work has been conducted on the following projects:

Blast Loading of Reinforced Masonry

Project Summary:

The goal of this research is to provide experimental evidence of the performance of Reinforced Masonry (RM) walls under realistic blast loading conditions with different pressure and impulse combinations to simulate real explosion scenarios.

The analytical work involves developing wall resistance functions, design charts, and single- and multi-degree-of-freedom models. Using the experimentally calibrated numerical models, an extensive wall blast performance database will be generated to cover different scenarios other than those tested.

Finally, the experimental, analytical, and numerical model results will be integrated into a performance assessment tool that will facilitate rapid screening and performance evaluation of RM components under different accidental and deliberate explosion scenarios.

Select Journal Articles:

Salem, Shady, Mohamed Ezzeldin, Michael Tait, and Wael El-Dakhakhni. “Resistance functions for blast fragility quantification of reinforced concrete block masonry shear walls.” Engineering Structures 233 (2021): 111531.

El-Hashimy, Tarek, Mohamed Ezzeldin, Michael Tait, and Wael El-Dakhakhni. “Reinforced masonry shear wall blast response limits for ASCE 59 and CSA S850.” Engineering Structures 239 (2021): 112183.

Energy Dissipation in Shear Wall Seismic Force Resisting System

Project Summary:

There is a real potential for a major earthquake to be the costliest disaster in Canadian history, and building owners are increasingly expecting solutions that can mitigate this risk. Meanwhile, current approaches for resisting seismic loads with reinforced masonry are not only associated with significant labour costs, but they also limit the range of structural heights for which reinforced masonry is a competitive building solution. Controlled rocking shows promise for addressing all these issues. In a controlled rocking system, selected parts of the structure are permitted to uplift from the foundation in response to seismic loads, and this rocking behaviour is controlled using supplemental energy dissipation and/or post-tensioning.

Recent NAMC Articles:

Yassin A., Ezzeldin M., and Wiebe L. (2019, June). “Numerical Modeling of Controlled Rocking Post-Tensioned Fully-Grouted Masonry Shear Walls With and Without Energy Dissipation.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1327–1339). Longmont, CO: The Masonry Society

Select Journal Articles:

Yassin, Ahmed, Mohamed Ezzeldin, Taylor Steele, and Lydell Wiebe. “Seismic collapse risk assessment of posttensioned controlled rocking masonry walls.” J. Struct. Eng 146, no. 5 (2020): 04020060.

Yassin, Ahmed, Mohamed Ezzeldin, and Lydell Wiebe. “Experimental assessment of controlled rocking masonry shear walls without post-tensioning.” Journal of Structural Engineering 148, no. 4 (2022): 04022018.

Reinforced Masonry under Seismic Risk

Project Summary:

The proposed research concentrates on design of masonry shear wall building for seismic loading and builds. Although masonry construction accounts for over 70% of the current stock of buildings in North America, its continued use as a major structural system has been severely impeded by concerns regarding earthquake resistance. Previous research, although comparatively scarce, clearly shows that with proper design, detailing, and construction, masonry can perform very well under seismic loading.

The proposed research is for a comprehensive series of tests and analyses to fully document behaviour of current masonry construction and improved behaviours resulting from innovative forms of construction.

This research will lead to proposals to modify design documents to account for the enhanced characteristics of properly designed masonry structures. Such changes will improve resistance to earthquake loading and reduce construction costs for masonry buildings.

Select Journal Articles:

Ezzeldin, Mohamed, Lydell Wiebe, and Wael El-Dakhakhni. “System-level seismic risk assessment methodology: Application to reinforced masonry buildings with boundary elements.” J. Struct. Eng 10 (2017).

Siam, Ahmad S., Wessam M. Hussein, and Wael W. El-Dakhakhni. “Scoring models for reinforced masonry shear wall maximum displacement prediction under seismic loads.” Engineering Structures 136 (2017): 511-522.

Siam, Ahmad, Wael El-Dakhakhni, and Zoe Li. “Seismic risk assessment of reinforced masonry structural wall systems using multivariate data analysis.” Engineering Structures 144 (2017): 58-72.

Siam, Ahmad S., Mohamed Ezzeldin, and Wael El-Dakhakhni. “Reliability of displacement capacity prediction models for reinforced concrete block shear walls.” In Structures, vol. 20, pp. 385-398. Elsevier, 2019.

Ezzeldin, Mohamed, Wael El-Dakhakhni, and Lydell Wiebe. “Experimental assessment of the system-level seismic performance of an asymmetrical reinforced concrete block–wall building with boundary elements.” Journal of Structural Engineering 143, no. 8 (2017): 04017063.

Ezzeldin, Mohamed, Wael El-Dakhakhni, and Lydell Wiebe. “Reinforced masonry building seismic response models for ASCE/SEI-41.” Journal of Structural Engineering 144, no. 1 (2018): 04017175.

Select Theses and HQP:

Mohamed Ezzeldin: https://macsphere.mcmaster.ca/handle/11375/20960

]]> University of Windsor https://www.canadamasonrydesigncentre.com/research/university-of-windsor/ Fri, 10 Nov 2023 20:42:28 +0000 https://www.canadamasonrydesigncentre.com/?p=13000

CMDC has worked in collaboration with Sreekanta Das from the University of Windsor.

Supporting Innovation through Research Partnerships

Work has been conducted on the following projects:

Stack Pattern Masonry Beams

Project Summary:

Clause 11 of the Canadian standard, CSA S304-14 currently does not allow stack pattern masonry beams to be designed and built with the provisions laid within. However, many architects opt for the stack pattern masonry look for aesthetic purposes not realizing the structural limitations it has. As a result, designers are placed in precarious position trying to reconcile the selected masonry pattern with the requirements and limitations of CSA S304.

Since the head joints in stack pattern masonry line up vertically, it is believed that this construction is weaker than the traditional running bond construction. However, since masonry beams must be fully-grouted, the effects of aligned head joints can be mitigated by increasing the grouted area of the units and the horizontal grout continuity in the beam.

Select Journal Articles:

Zohrehheydariha, Jamshid, Sreekanta Das, and Bennett Banting. “Effect of unit bonding patterns on the structural performance of loadbearing concrete block masonry beams.” Journal of Structural Engineering 145, no. 1 (2019): 04018233.

Heydariha, Jamshid Zohreh, Sreekanta Das, and Bennett Banting. “Effect of grout strength and block size on the performance of masonry beam.” Construction and Building Materials 157 (2017): 685-693.

Select theses and HQP:

Jamshid Zohrehheydariha: https://scholar.uwindsor.ca/etd/7314/

Shear Resistance of Masonry Beams and the Chi Factor

Project Summary:

Masonry design standards require stirrups to be in contact with horizontal reinforcement. The placement of shear stirrups in beams built with narrow masonry concrete blocks becomes challenging due to cell changes as the block size reduces. Similarly, the smallest standard shear reinforcing bar size (i.e. 10M rebar) with a standard hook is complicated for a mason to achieve in the field.

Hence, this study was carried out to investigate the feasibility of using 8 mm steel bars and readily available bed joint wire (i.e. steel wire mesh) mesh which is commonly used as a horizontal reinforcement, as potential shear (vertical) reinforcement alternatives to enhance the flexural capacity and reduce the shear crack of masonry concrete beams.

The findings from this study also showed that the Canadian masonry design standard value for the chi (χ) factor is potentially conservative.

Select Journal Articles:

Penales, Jeeric, Jamshid Zohrehheydariha, Sreekanta Das, and Bennett Banting. “Structural Behavior of Masonry Beams with Alternative Shear Reinforcement.” Journal of Structural Engineering 147, no. 3 (2021): 04021002.

Select Theses and HQP: :

Jeeric Penales: https://scholar.uwindsor.ca/etd/8176/

]]> University of British Columbia https://www.canadamasonrydesigncentre.com/research/university-of-british-columbia/ Fri, 10 Nov 2023 20:34:51 +0000 https://www.canadamasonrydesigncentre.com/?p=12995

CMDC has worked in collaboration with Svetlana Brzev and Tony Yang from the University of British Columbia.

Supporting Innovation through Research Partnerships

Work has been conducted on the following projects:

Flanged Boundary Elements on Reinforced Masonry Shear Walls

Project Summary:

Reinforced masonry shear walls (RMSWs) have been demonstrated to possess adequate ductility and energy dissipation characteristics for seismic design applications. However, slender RMSWs, characterized by high height-to-thickness (h/t) ratios, may be vulnerable to out-of-plane instability under in-plane seismic loading.

Out-of-plane instability is a failure mechanism that affects RMSW end-zone regions subjected to cycles of tensile strain, followed by compressive strain during load reversal. This failure mechanism has the potential to cause unexpected and rapid strength degradation or collapse, if not considered in design.

The Canadian masonry design standard, CSA S304-14, prescribes h/t limits for the seismic design of RMSWs to prevent out-of-plane instability, however, no experimental testing verifies these limits. Moreover, the h/t limits are independent of the cross-sectional shape of the RMSW, despite the wall response being significantly influenced by this parameter. At a given drift demand, T-shaped RMSWs, i.e. rectangular RMSWs with flanged boundary elements at one end-zone, tend to produce higher strains at the end-zone without flanged boundary elements as compared to the end-zones of rectangularly-shaped RMSWs. This may increase the risk of out-of-plane instability affecting T-shaped RMSWs.

Select Journal Articles:

Robazza, B.R., S. Brzev, T.Y. Yang, K.J. Elwood, D.L. Anderson, and B. McEwen. “Seismic Behaviour and Design Code Provisions for Predicting the Capacity of Ductile Slender Reinforced Masonry Shear Walls.” Engineering Structures 222 (2020): 110992.

Robazza, B.R., T.Y. Yang, S. Brzev, K.J. Elwood, D.L. Anderson, and W. McEwen. “Response of Slender Reinforced Masonry Shear Walls with Flanged Boundary Elements under in-Plane Lateral Loading: An Experimental Study.” Engineering Structures 190 (2019): 389–409.

Robazza, B. R., S. Brzev, and T. Y. Yang. “An experimental study on slender reinforced masonry shear walls subjected to in-plane reversed cyclic loading.” In Brick and Block Masonry-From Historical to Sustainable Masonry, pp. 483-490. CRC Press, 2020.

Robazza,B.R.,  Brzev,S., Yang,T.Y., Elwood, K.J., Anderson, D.L., and McEwen,W. (2018). Seismic Behaviour of Slender Reinforced Masonry Shear Walls under In-Plane Loading: An Experimental Investigation, Journal of Structural Engineering, ASCE, 144(3): 04018008.

Robazza,B.R.,  Brzev,S., Yang,T.Y., Elwood, K.J., Anderson, D.L., and McEwen,W. (2017). A Study on the Out-of-Plane Stability of Ductile Reinforced Masonry Shear Walls Subjected to in-Plane Reversed Cyclic Loading. The Masonry Society Journal, 35(1): 73-82.

Azimikor, N., Brzev, S., Elwood, K., Anderson, D.L., and McEwen,W. (2017). Out-Of-Plane Instability of Reinforced Masonry Uniaxial Specimens Under Reversed Cyclic Axial Loading. Canadian Journal of Civil Engineering, Vol. 44: 367–376

Robazza,B.R.,  Brzev,S., Yang,T.Y., Elwood, K.J., Anderson, D.L., and McEwen,W. (2017). Effects of Flanged Boundary Elements on the Response of Slender Reinforced Masonry Shear Walls: An Experimental Study. Proceedings of the 13th Canadian Masonry Symposium, Halifax, NS, Canada.

Seismic Behaviour of Reinforced Masonry Buildings

 

Project Summary:

Reinforced masonry (RM) has been used in Canada for more than 50 years, mostly for construction of low- and mid-rise buildings. The National Building Code of Canada 2015 (NBC 2015) permits the use of Ductile Shear Wall class for tall masonry buildings, but the height limit was set to 60 m at sites with moderate seismic hazard and 40 m for high seismic hazard sites.

Only a few tall (15+ storey high) RM buildings have been constructed in Canada to date, mostly at sites with low to moderate seismic hazard.

Recent NAMC Articles:

Brzev S., Reiter M., Pérez-Gavilán J., Quiun D., Membreño M., Hart T., and Sommer D. (2019, June). “Confined Masonry: The Current Design Standards.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 50–62). Longmont, CO: The Masonry Society

]]> Queen’s University https://www.canadamasonrydesigncentre.com/research/queens-university/ Fri, 10 Nov 2023 20:28:00 +0000 https://www.canadamasonrydesigncentre.com/?p=12989

CMDC has worked in collaboration with Mark Green from Queen's University.

Supporting Innovation through Research Partnerships

Work has been conducted on the following projects:

Recycled Aggregate for Block Production

Project Summary:

To produce high quality concrete masonry units, block producers generally define concrete mixes by a trial process that makes it difficult to test new types of aggregates, such as Recycled Concrete Aggregate (RCA), because it interferes with production efficiency. Furthermore, block producers normally produce block in runs of thousands of units at a time, which makes it difficult to make many trial mixes with different RCA replacement ratios. The use of RCA for the production of concrete masonry units is explored in a laboratory setting by simulating the industrial manufacturing process.

Select Journal Articles:

Sarhat, Salah, Sheikh Hamza Rizwan, Mohammad Gibran Mirza, Mark Green, and Bennett Banting. “The Use of Recycled Aggregates in the Production of Concrete Masonry Units: A Critical Review and a Statement on the Current Research Needs.” In Masonry 2022. ASTM International, 2022.

Select Theses and HQP:

Mohammad Gibran Mirza: https://qspace.library.queensu.ca/handle/1974/27456

]]> McGill University https://www.canadamasonrydesigncentre.com/research/mcgill-university/ Fri, 10 Nov 2023 19:36:49 +0000 https://www.canadamasonrydesigncentre.com/?p=12981

CMDC has worked in collaboration with Daniele Malomo from McGill University.

Supporting Innovation through Research Partnerships

Work has been conducted on the following projects:

Adapting Masonry Standards to Climate Change

Project Summary:

Today’s changing climate is demanding more and more from our buildings. In Canada, this means coping with extreme winds and temperature changes, as well as changing rain patterns and exposure to freeze-thaw conditions. At the same time, energy codes are forcing major changes to the way we insulate and detail our buildings to maximize energy efficiency and reduce greenhouse gas emissions. Masonry has long proven itself to be a durable construction material, however new construction methods are exposing the materials to new pressures, and results from available previous research is getting less applicable to current conditions.

Dr. Malomo’s research project aims to address several of these knowledge gaps by studying the causes of cracking in clay brick and concrete block construction, as well as the strength and behaviour of modern veneer ties and shelf angle supports that span through very thick layers of insulation.

Through testing of small masonry assemblages and computer analysis of larger structures, the goal is to support the further development of building codes and standards ensure masonry buildings remain durable and energy efficient over their entire service life.

Recent NAMC Articles:

Menun, A., Das, t., Saad, L., Sparling, A., and Malomo, D. (2023, June). “A New 2-Step Testing Method for Measuring Moisture-Induced Shrinkage of Concrete Blocks, Mortar and Masonry Assemblies.” In Proceedings of the Fourteenth North American Masonry Conference. Paper presented at the 14th North American Masonry Conference, Omaha, Nebraska (pp. 99-108). Longmont, CO: The Masonry Society.

]]> University of Calgary https://www.canadamasonrydesigncentre.com/research/university-of-calgary/ Fri, 10 Nov 2023 18:09:18 +0000 https://www.canadamasonrydesigncentre.com/?p=12960

CMDC has worked in collaboration with Nigel Shrive from the University of Calgary.

Supporting Innovation through Research Partnerships

Nigel Shrive

University Profile

Work has been conducted on the following projects:

Eco-Friendly Ductile Cementitious Composites (EDCC)

Project Summary:

A large proportion of the existing building stock in Canada is composed of loadbearing Un-Reinforced Masonry (URM). In seismic zones, this type of construction can pose a safety risk for the occupants as it may not meet the structural resistance and / or ductility requirements of contemporary building codes.

An innovative Eco-Friendly Ductile Cementitious Composite (EDCC) is currently under investigation for possible use as a reinforcing material for retrofitting existing URM structures.

The retrofitting process involves applying a layer of EDCC to the surface of URM walls to improve their resistance and ductility.

Recent NAMC Articles:

Parsekian G. and Shrive N. (2019, June). “Preliminary Results on Surface Coating Strengthening Concrete Block Masonry with Eco-Friendly Ductile Cementitious Composite.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 696–706). Longmont, CO: The Masonry Society.

Select Journal Articles:

Veronese, R.B.A., Madeiros, W.A., Parsekian, G.A., and Shrive, N.G. ”Numerical Analysis of Eco-friendly Ductile Cementitious Composite Influence on Structural Masonry Reinforcement.” Engineering Structures, 252, 113686, 2022.

Select Theses and HQP:

Pedram Kaheh: https://prism.ucalgary.ca/handle/1880/106391

Analysis of Slender Masonry Walls

Project Summary:

The Canadian masonry design standard appears to underestimate the capacity of slender masonry walls, reducing efficiency in the use of the material. The capacity of a slender concrete masonry wall subjected to axial loads is affected mainly by its slenderness ratio, the eccentricity of the applied load, the deflected shape of the wall resulting from the ratio of end eccentricities and its flexural rigidity.

To take account of slenderness and second order effects, the current Canadian design standard allows use of the moment magnifier method, or calculation of the P-Δ effect. Several investigations indicate that these approaches are generally appropriate for considering the effects of secondary moments. The main reason for the underestimation of the capacity is the effective flexural rigidity used in the code. Due to material nonlinearity and a reduction of the cross-sectional depth caused by tensile cracking, the effective flexural rigidity is limited to 0.4 and 0.25 times the initial flexural rigidity for unreinforced and reinforced masonry, respectively.

Recent NAMC Articles:

Haleem, B., Ahmed, A., Rathnayake, H., and Shrive, N.G. (2023, June) “An approach for numerically improving the parameters of the moment magnifier method.” In Proceedings of the Fourteenth North American Masonry Conference. Paper presented at the 14th North American Masonry Conference, Omaha, Nebraska (pp. 131-139). Longmont, CO: The Masonry Society

Iskander, G., Ahmed, A., and Shrive, N.G. (2023, June) “Experimentally testing eccentrically loaded full and half scale concrete masonry.” In Proceedings of the Fourteenth North American Masonry Conference. Paper presented at the 14th North American Masonry Conference, Omaha, Nebraska (pp. 238-247). Longmont, CO: The Masonry Society

Select Journal Articles:

Isfeld, Andrea C., Anna Louisa Müller, Mark Hagel, and Nigel G. Shrive. “Analysis of safety of slender concrete masonry walls in relation to CSA S304-14.” Canadian Journal of Civil Engineering 46, no. 5 (2019): 424-438.

Isfeld, Andrea C., Anna L. Müller, Mark Hagel, and Nigel G. Shrive. “Testing and finite element modelling of concrete block masonry walls under axial and out-of-plane loading.” International Journal of Masonry Research and Innovation 6, no. 1 (2021): 60-80.

Bogoslavov, M., Shrive, N.G. “On the Effective Stiffness of Slender Concrete Masonry Walls in the Canadian Masonry Standard” Masonry International, (winner, best student project, International Masonry Society, 2022), in press, 2023

Testing, Modelling, and Reliability Analysis of Masonry

Project Summary:

Despite the high level of vulnerability of unreinforced masonry structures under applied loads and the importance of their reliability evaluation, there is no formal methodology to assess the reliability of historic masonry structures. Therefore, a step-by-step methodology for assessing the reliability level of historic masonry structures is being developed.

To develop an appropriate determinate methodology, estimations of probabilistic models of structural resistance and load effects are required to formulate a limit state function. The stochastic characteristics of construction materials play key roles in the determination of probabilistic models of structural resistance. Codes of practice recommend values as well as the best fit distributions for different material characteristics.

As codes are necessarily conservative and are also generally aimed at design or assessment with modern masonry materials, the use of code values for historical structures may lead to inaccurate reliability assessment. Destructive testing of a historic masonry structure or its components in order to get more realistic information regarding the material properties is not recommended as such tests may lead to irreparable damage to these valuable structures.

Recent NAMC Articles:

Pasquantonio R., Parsekian G., Fonseca F., and Shrive N. (2019, June). “Interface Parameters Between Masonry Concrete Blocks and Mortar for Modeling of Masonry Structures.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1055–1064). Longmont, CO: The Masonry Society

 Isfeld A., Hagel M., and Shrive N. (2019, June). “Finite Element Analysis of Hollow Concrete Block Masonry Walls.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1110–1122). Longmont, CO: The Masonry Society.

Select Theses and HQP:

Setare Seyedain Boroujeni: https://prism.ucalgary.ca/handle/11023/3855

Masonry Arch Retaining Walls

Project Summary:

Masonry arches have a long history of use in construction and are a very efficient method for resisting applied loads by taking advantage of the high compressive strength of the material and inducing minimal tensile stresses. Contemporary structural design approaches favor the use of beam and flexural wall elements to resist distributed loads through a flexural resistance mechanism in which tensile stresses are resisted by reinforcing bars.

Although simple to design and construct this type of structural masonry element is somewhat inefficient in its use of materials since the masonry material in tension is generally deemed not to contribute to the resistance. This research project aims to demonstrate how an unreinforced masonry arch system may be used to efficiently resist horizontal soil pressures for low-rise retaining wall structures.

Recent NAMC Articles:

Rathnayake, H., Ahmed, A., Iskander, G., Shrive, N.G., (2023, June). “Influence of Boundary Conditions on the Performance of Block Arch Masonry Retaining Walls.” In Proceedings of the Fourteenth North American Masonry Conference. Paper presented at the 14th North American Masonry Conference, Omaha, Nebraska (pp. 888-898). Longmont, CO: The Masonry Society

Select Journal Articles:

Kurukulasuriya, M., Shrive N.G., “Flat Arch Masonry Retaining wall” Masonry International, 33 (3), 64-74, 2021. (winner, 2020 best graduate project award, International Masonry Society)

Kurukulasuriya, M., Shrive N.G., “Innovative Masonry Arch Design for Low-rise Retaining Walls” Invited, translated and published in Portuguese, Revista Estrutura (Brazilian structures association magazine), 12, 6, 28-34, March 2023.

Select Theses and HQP: :

Maithree Chiranthya Kurukulasuriya: https://prism.ucalgary.ca/items/cc112d40-c6b3-497e-9623-8674887b6ff8

Partially Grouted Masonry Shear Walls

Project Summary:

Reinforced masonry shear walls are commonly used to form the lateral load resisting system of reinforced masonry buildings. This type of construction is widely used across Canada and developments in design approaches and standards have allowed increasingly efficient use of materials. However, whereas fully grouted reinforced masonry exhibits a well-established shear behaviour akin to that of reinforced concrete, additional complexity is introduced for partially-grouted reinforced masonry shear walls.

This research project examines the behaviour and various possible modes of failure of partially-grouted reinforced masonry shear walls in view of developing reliable analysis and design tools.

Recent NAMC Articles:

Zhu, J., Ahmed, A., Iskander, G., Shrive, N.G., (2023, June). “Size Effect on Concrete Masonry Shear Strength Under Various Grouting and Precompression Conditions.” In Proceedings of the Fourteenth North American Masonry Conference. Paper presented at the 14th North American Masonry Conference, Omaha, Nebraska (pp. 78-88). Longmont, CO: The Masonry Society

Pan, H., Isfeld, A.C., Shrive N.G. (2019, June). “The failure of partially grouted masonry walls subject to in-plane shear is affected by the stiffness of the grouted “frame”.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1227–1239). Longmont, CO: The Masonry Society.

Select Journal Articles:

Zhu, J., Shrive, N.G., “Partially Grouted Concrete Masonry Shear Walls Subject to In-Plane Shear Load: A Critical Review” IBRACON Materials and Structures Journal, invited, 16, 3, e16301, 2023.

Rizaee, S., Lissel, S.L., Shrive N.G., “The Effect of the Amount, Distribution and End Anchorage Conditions of Bond Beam Reinforcement on the Behaviour of Concrete Masonry Shear Walls” Canadian Journal of Civil Engineering, 48 (12), 1583-1600, 2021.

Shrive N.G., Dhanasekar, M., Masia, M.J., Page, A.W., “The Response of Wide-Spaced Partially Grouted Concrete Masonry to In-Plane Shear – State of the Art and Research Needs” International Journal of Masonry Research and Innovation, 3 (4), 369-381, 2018

Select Theses and HQP:

Huina Pan: https://prism.ucalgary.ca/handle/1880/106830

]]> University of Alberta https://www.canadamasonrydesigncentre.com/research/university-of-alberta/ Fri, 10 Nov 2023 16:15:20 +0000 https://www.canadamasonrydesigncentre.com/?p=12931

CMDC has worked in collaboration with Carlos Cruz-Noguez and Yong Li from The University of Alberta.

Supporting Innovation through Research Partnerships

Work has been conducted on the following projects:

In-Plane Shear Strength of Partially Grouted Walls

Project Summary:

Reinforced masonry (RM) shear walls are often used as the primary load-resisting system against lateral loads in low- and medium-rise masonry structures. RM walls can be fully grouted (FG) or partially grouted (PG) with the latter option being generally more economical, and thus, widely used in the masonry industry.

While expected to remain sufficiently stiff under service loads, a masonry shear wall is also expected to exhibit a ductile response under lateral load at the ultimate state. However, if the behaviour is shear-critical, failure may occur suddenly.

Recent studies have shown that current design provisions do not predict the shear strength of PG shear walls with consistent accuracy over the range of design variables commonly found in practice. Research has shown that in some cases, design provisions may lead to potentially unsafe designs.

Recent NAMC Articles:

Ba Rahim A., Hung J., Pettit C., and Cruz-Noguez C. (2019, June). “Effect of Interior Vertical Reinforcement on the Performance of Partially Grouted Masonry Shear Walls.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1216–1226). Longmont, CO: The Masonry Society.

Hudson K., Pettit C., Ba Rahim A., Hung J., and Cruz-Noguez C. (2019, June). “An Investigation of the Canadian Code-Based Shear Strength Equation of Partially Grouted Masonry Shear Walls.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1252–1260). Longmont, CO: The Masonry Society.

Ba Rahim A., Pettit C., Cruz-Noguez C., and Hung J. (2023, June) “An Analysis Model for Partially Grouted Shear Walls Using Macro-Modelling: Importance of Reporting Joint Shear Strength.” In Proceedings of the Fourteenth North American Masonry Conference. Paper presented at the 14th North American Masonry Conference, Omaha, Nebraska (pp. 164-175). Longmont, CO: The Masonry Society.

Recent Journal Articles:

Cruz-Noguez, Carlos. “Artificial Neural Network to Predict the Shear Strength of Partially Grouted Masonry Walls”. The Masonry Society Journal. (2023, ahead of print)

Out-of-Plane Resistance of Slender RM Walls

Project Summary:

Load bearing slender masonry walls (SMWs) are widely used in single-storey construction in Canada (for example in school gymnasiums, warehouses, etc.). However, design limits imposed on these walls (CSA S304-14; TMS 402-13) tend to be stringent, in terms of strength and stability. This puts the masonry industry at a disadvantage as a construction alternative compared to other structural options.

Research and innovation in slender masonry wall design has been scarce since the 1980s, when working stress and prescriptive-based design were common. This has had a negative impact on the use of conventional slender masonry walls, as limit states and objective-based design have since been adopted.

Adding to these challenges, newer building energy code regulations (NRC 2015 and 2017) place further constraints that impact the design, cost, and performance of SMWs.

Recent NAMC Articles:

Guzmán Sánchez O., Cruz-Noguez C., and Li Y. (2019, June). “Reliability-Based Analysis Model of Slender Masonry Walls.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1148–1158). Longmont, CO: The Masonry Society.

Pettit C., Entz J., Guzmán Sánchez O., Cruz-Noguez C., and Banting B. (2019, June). “Tall Masonry Walls with In-Line Cage Reinforcing.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1190–1201). Longmont, CO: The Masonry Society.

Alonso, A., Gonzalez, R., Elsayed, M., Tomlinson, D., and Cruz-Noguez, C. (2023, June). “Out-Of-Plane Behavior of a Slender Masonry Wall with Different Base Stiffnesses.” In Proceedings of the Fourteenth North American Masonry Conference. Paper presented at the 14th North American Masonry Conference, Omaha, Nebraska (pp. 974-983). Longmont, CO: The Masonry Society.

Select Journal Articles:

Sustersic, H., Stubbs, D., Peterson, R., Bennett, R., Pettit, Clayton., Flisak, Bart, Erdogmus, Ece, Thompson, Jason, Banting, Bennett, Cruz-Noguez, Carlos. “Canada/US Out-of-Plane Reinforced Masonry Walls Design Provisions Comparison.” The Masonry Society Journal. (2022, ahead of print)

Tolou Kian, Mohammad Javad, and Cruz-Noguez, Carlos. “Plastic hinge length and inelastic rotational capacity of reinforced concrete shear walls detailed with self-centering reinforcement”. Engineering Structures, 279 (2023): 115518.

Pettit, Clayton, Erum Mohsin, Carlos Cruz-Noguez, and Alaa Elwi. “Experimental testing of slender load-bearing masonry walls with realistic support conditions.” Canadian Journal of Civil Engineering 49, no. 1 (2022): 95-108.

Pettit, Clayton, and Carlos Cruz-Noguez. “Effect of Rotational Base Stiffness on the Behavior of Load-Bearing Masonry Walls.” Journal of Structural Engineering 147, no. 12 (2021): 04021215.

Zeng, Bowen, Yong Li, and Carlos Cruz Noguez. “Modeling and parameter importance investigation for simulating in-plane and out-of-plane behaviors of un-reinforced masonry walls.” Engineering Structures 248 (2021): 113233.

Metwally, Ziead, Bowen Zeng, and Yong Li. “Probabilistic Behavior and Variance-Based Sensitivity Analysis of Reinforced Concrete Masonry Walls Considering Slenderness Effect.” ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering 8, no. 4 (2022): 04022051.

R-Value Estimation for Masonry

Project Summary:

New stringent energy codes and guidelines for the construction of energy-efficient buildings compatible with net-zero emissions infrastructure are drawing increasing attention to the insulation and energy-performance of buildings.

Traditional insulated masonry cavity wall systems, designed for compliance with previous energy codes, incorporated modest amounts of insulation, ranging from 25 mm to 50 mm to achieve prescriptive requirements. Contemporary energy codes now require significantly higher insulation R-values and attract increasing attention to the effect of thermal bridging, such as that which occurs in masonry ties, shelf angles, and other elements that penetrate through the insulation.

Detailed analysis of existing insulated masonry cavity wall systems is needed to establish their thermal performance to facilitate design, and new high-performance building envelope systems for masonry structure must be developed.

Recent NAMC Articles:

Pettit C., Salazar J., Cruz-Noguez C., and Hagel M. (2019, June). “Experimental Determination of the Behavior of Lag Screws in Masonry Veneer Shelf Angles.” In P.B. Dillon & F.S. Fonseca (Eds.), Proceedings of the Thirteenth North American Masonry Conference. Paper presented at the 13th North American Masonry Conference, Salt Lake City, Utah (pp. 1757–1768). Longmont, CO: The Masonry Society.

Select Journal Articles:

Ismaiel, Maysoun, Yuxiang Chen, Carlos Cruz-Noguez, and Mark Hagel. “Thermal resistance of masonry walls: a literature review on influence factors, evaluation, and improvement.” Journal of Building Physics 45, no. 4 (2022): 528-567.

Hagel, Mark D., Gary R. Sturgeon, and Carlos Cruz-Noguez. “A service life model of metal ties embedded in the mortar joints of brick veneer walls with applications to reinforced concrete.” Canadian Journal of Civil Engineering 46, no. 11 (2019): 1043-1053.

Ismaiel, Maysoun, Maged Gouda, Yong Li, and Yuxiang Chen. “Airtightness evaluation of Canadian dwellings and influencing factors based on measured data and predictive models.” Indoor and Built Environment (2022): 1420326X221121519.

Ismaiel, Maysoun, Lindsey Westover, and Yuxiang Chen. “An efficient approach for thermal design of masonry walls using design charts and R-value multipliers.” Journal of Building Performance Simulation 15, no. 6 (2022): 788-808.

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