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23 records – page 1 of 3.

Sound insulation performance of elevator shaft walls built with nail-laminated timber panels - Exploratory tests and preliminary results

https://library.fpinnovations.ca/en/permalink/fpipub40172
Author
Pirvu, Ciprian
Date
March 2016
Material Type
Research report
Field
Sustainable Construction
Author
Pirvu, Ciprian
Contributor
Natural Resources Canada. Canadian Forest Service
Date
March 2016
Material Type
Research report
Physical Description
28 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Building construction
Laminate product
Performance
Wood frame
Series Number
Midrise Wood Frame Construction
Taller and Larger Wood Buildings
W3296
Location
Vancouver, British Columbia
Language
English
Abstract
As 6-storey wood-frame, massive-timber and hybrid wood buildings are increasingly accepted by more jurisdictions across Canada, there is a need to develop reliable elevator shaft designs that meet the minimum structural, fire, and sound requirements in building codes. Elevator shaft walls constructed with wood-based materials have the advantages of material compatibility, use of sustainable materials, and ease of construction. In this exploratory study, selected elevator shaft wall designs built with nail-laminated-timber (NLT) structural elements were tested to investigate their sound insulation performance because little is known about the sound insulation performance of such wall assemblies. The tests were carried out in an acoustic mock-up facility in accordance to standard requirements, and provide preliminary data on the sound insulation performance of elevator shaft walls built with NLT panels. Four different elevator shaft walls built with NLT panels were tested and their measured apparent sound insulation class (ASTC) ratings ranged from 18 to 39 depending on their construction details. Some of the reasons that may have contributed to the ASTC ratings obtained for the elevator shaft walls described in this report as well as recommendations for future designs were provided. It is recommended to continue improving the sound insulation of elevator shaft walls built with NLT panels to meet or exceed the minimum requirements in building codes.
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In-situ testing of wood innovation and design centre: floor vibration, building vibration, and sound insulation performance

https://library.fpinnovations.ca/en/permalink/fpipub53039
Author
Hu, Lin J.
Pirvu, Ciprian
Ramzi, Redouane
Date
July 2015
Material Type
Research report
Field
Sustainable Construction
Author
Hu, Lin J.
Pirvu, Ciprian
Ramzi, Redouane
Contributor
Forestry Innovation Investment
Date
July 2015
Material Type
Research report
Physical Description
49 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Testing
Performance
Wood
Buildings
Language
English
Abstract
This report describes the building, tested floor and wall assemblies, test methods, and summarizes the test results. The preliminary performance data provides critical feedback on the design of the building for resisting wind-induced vibration and on the floor vibration controlled design. The data can be further used to validate the calculation methods and tools/models of dynamic analysis. Originally confidential to FII, they have provided permission to make the report available.
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Development of design values for hem-fir cross-laminated timber

https://library.fpinnovations.ca/en/permalink/fpipub44204
Author
Pirvu, Ciprian
Date
March 2015
Material Type
Research report
Field
Sustainable Construction
Author
Pirvu, Ciprian
Date
March 2015
Material Type
Research report
Physical Description
33 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Building Systems
Subject
British Columbia
Laminate product
Standards
Tsuga Heterophylla
Design
Series Number
BC Coastal Forest Industry
Language
English
Abstract
The North American product standard for performance-rated cross-laminated timber (CLT), ANSI/APA PRG 320, was published in 2012. The standard recognizes the use of all major Canadian and US softwood species groups for CLT manufacturing and provides design properties for specific CLT layups with visually graded and E-rated/MSR laminations. While design properties for CLT layups with Spruce-Pine-Fir and Douglas fir-Larch laminations are specified in the current standard, no design properties are indicated for CLT layups with Hem-Fir laminations. Design properties for two proposed CLT grades manufactured with Hem-Fir lumber were developed. These include a CLT layup with visually graded laminations and another layup with E-rated/MSR laminations. Design properties for these two CLT layups were calculated separately for use in Canada and the US. Supporting information for the addition of design properties for Hem-Fir grades to the CLT product standard was generated. Recommended amendments to the CLT product standard include durability and wood failure requirements of bondlines, and design properties for Hem-Fir layups.
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Time-dependent behavior of cross-laminated timber

https://library.fpinnovations.ca/en/permalink/fpipub43013
Author
Pirvu, Ciprian
Date
March 2014
Material Type
Research report
Field
Sustainable Construction
Author
Pirvu, Ciprian
Contributor
Natural Resources Canada. Canadian Forest Service.
Date
March 2014
Material Type
Research report
Physical Description
70 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Building construction
Design
Laminate product
Panels
Timber
Series Number
Transformative Technologies No. 1.1.12
W-3092
Language
English
Abstract
Cross laminated timber (CLT) panels were manufactured and tested to assess their time dependent behaviour. This study is intended to help guide the development of an appropriate test method and acceptance criteria to account for duration of load and creep effects in the design of structures using CLT. Nine CLT panels of different qualities and using different wood species combinations were manufactured at a pre-commercial pilot plant out of local wood species. The CLT panels manufactured in this study were pressed at about 54% lower pressure than the minimum vertical pressure specified by the adhesive manufacturer due to a limitation of the press, so the CLT panels are viewed as a simulated defective sample, which may occur in a production environment due to material- or process-related issues. Full-size CLT panels were initially tested non-destructively to assess their bending stiffness. Then, billets were ripped from the full-size CLT panels, and tested to failure in 1-minute and 10-hour ramp tests, or assessed in creep tests under sustained load. The constant loads imposed on the CLT billets tested in creep were calculated as to allow for a maximum deflection of L/180. Following two cycles of loading and relaxation, the CLT billets tested in creep were further tested to failure at the end. The principles of ASTM D6815-09 and those of an in-house FPInnovations protocol were applied to assess the time dependent behavior of the CLT billets. The main test findings are summarized below:
In terms of residual stiffness, the percentage change in the initial bending stiffness for the CLT billets subjected to the 10-hour ramp test varied between 0-5%, showing a 3% drop in stiffness on average, while that for the CLT billets tested in creep ranged between 0-3%, showing a 1% stiffness drop on average. These are regarded as relatively small changes in bending stiffness.
In general, decreasing creep rates were observed on most of the CLT billets especially in the first cycle up to 90 days. The creep rates went up after 120 days of loading due to an increase in temperature and relative humidity conditions, which greatly affect the rate of deflection and recovery of wood products.
Fractional deflections were calculated for all the CLT billets after 30-day intervals and found to be less than or equal to 1.43.
Creep recovery was above 36% after 30-day, 60-day, and 90-day recovery periods in the first cycle. However, in the second cycle, creep recovery for some CLT billets dropped below 20% for certain time periods. ASTM D6815-09 provides specifications for evaluation of duration of load and creep effects of wood and wood-based products. The standard was designed to accommodate wood products that can be easily sampled, handled, and tested under load for minimum 90 days and up to 120 days. The standard requires a minimum sample size of 28 specimens. Because of its large dimensions, CLT products are not feasible for experiments requiring such large sample sizes. However, the findings of this study revealed potential for some of the acceptance criteria in ASTM D6815-09 to be applied to CLT products. The CLT billets in this study were assessed in accordance to the creep rate, fractional deflection, and creep recovery criteria in ASTM D6815-09 standard. All CLT billets tested in this study showed (1) decreasing creep rates after 90/120 days of loading, (2) fractional deflections less than 2.0 after 90-day loading, and (3) higher creep recovery than 20% after 30 days of unloading, as required by ASTM D6815-09. A single replicate billet was used per CLT configuration instead of the minimum sample size required by the standard which may have an effect on the findings.
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Effect of adhesive cure on quality of fingerjoined lumber : updated report

https://library.fpinnovations.ca/en/permalink/fpipub39405
Author
Pirvu, Ciprian
Date
March 2012
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Pirvu, Ciprian
Contributor
Natural Resources Canada. Canadian Forest Service.
Date
March 2012
Material Type
Research report
Physical Description
56 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Lumber
Composites
Adhesives
Series Number
Value to Wood No. FPI 121W
W-2888
Location
Vancouver, British Columbia
Language
English
Abstract
The relationship between proof load level of fingerjoined lumber and degree of cure of adhesive bonds was investigated. Tension tests were completed for two different degrees of cure for two different adhesives. The proof load level determined for the partially cured joints did not cause damage to the joints that survived the proof test. Preliminary guidelines for determining appropriate proof load levels for testing fingerjoined lumber with partially cured joints were proposed. The proposed guidelines will need to be validated through mill trials to demonstrate their efficacy and reliability to the manufacturer and third party inspection agency. Keywords: fingerjoined lumber; tension proof testing/loading; partially cured adhesive bonds.
Curing rate
Finger jointed lumber
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Refinement of duration of load test protocols

https://library.fpinnovations.ca/en/permalink/fpipub39406
Author
Pirvu, Ciprian
Date
March 2012
Material Type
Research report
Field
Sustainable Construction
Author
Pirvu, Ciprian
Contributor
Natural Resources Canada. Canadian Forest Service.
Date
March 2012
Material Type
Research report
Physical Description
40 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Building Systems
Subject
Strength load bearing
Mechanical properties
Specifications
Loads
Specification
Series Number
Canadian Forest Service No. FRII-3.17
W-2892
Location
Vancouver, British Columbia
Language
English
Abstract
Duration of load (DOL) and creep effects characterize rheological behaviour of wood and are of critical importance to timber engineering. These effects are accounted for in the engineering design codes with adjustment factors for structural wood and wood-based products. Various methods are used worldwide for the evaluation of DOL and creep effects and for determination of appropriate adjustment factors. A review of the major international codes for engineering design in wood was carried out to understand how DOL and creep are taken into account in these codes and provide recommendations on how to level out the main differences between the codes. It is recommended to adopt an internationally recognized method for evaluation of DOL and creep, and suggestions for the contents of such a method are provided. Statisticians were engaged to evaluate the damage accumulation models used in wood industry for assessing DOL and creep effects of wood products. The research undertaken yielded answers to whether the mathematical models can be improved, if times-to-failure for ramp and constant load tests can be approximated by Weibull or log-normal distributions, and whether some model parameters can be assumed constant and other treated as random effects. An experimental study was carried out to support the statistical work. The results of the study were used in statistical simulations to estimate the parameters used in the damage accumulation models in an attempt to refine the current models.
Strength - Load bearing - Influence of duration
Strength - Load bearing - Specifications
Strength - Load bearing - Tests
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Checking in CLT panels : an exploratory study

https://library.fpinnovations.ca/en/permalink/fpipub2772
Author
Casilla, Romulo C.
Lum, Conroy
Pirvu, Ciprian
Wang, Brad J.
Date
December 2011
Edition
39389
Material Type
Research report
Field
Sustainable Construction
Author
Casilla, Romulo C.
Lum, Conroy
Pirvu, Ciprian
Wang, Brad J.
Date
December 2011
Edition
39389
Material Type
Research report
Physical Description
29 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Building Systems
Subject
Panels tests
Panels
Laminate product
Building construction
Series Number
Transformative Technologies # TT1.07
W-2877
Location
Vancouver, British Columbia
Language
English
Abstract
A study was conducted with the primary objective of gathering information for the development of a protocol for evaluating the surface quality of cross-laminated timber (CLT) products. The secondary objectives were to examine the effect of moisture content (MC) reduction on the development of surface checks and gaps, and find ways of minimizing the checking problems in CLT panels. The wood materials used for the CLT samples were rough-sawn Select grade Hem-Fir boards 25 x 152 mm (1 x 6 inches). Polyurethane was the adhesive used. The development of checks and gaps were evaluated after drying at two temperature levels at ambient relative humidity (RH). The checks and gaps, as a result of drying to 6% to 10% MC from an initial MC of 13%, occurred randomly depending upon the characteristics of the wood and the manner in which the outer laminas were laid up in the panel. Suggestions are made for minimizing checking and gap problems in CLT panels. The checks and gaps close when the panels are exposed to higher humidity. Guidelines were proposed for the development of a protocol for classifying CLT panels into appearance grades in terms of the severity of checks and gaps. The grades can be based on the estimated dimensions of the checks and gaps, their frequency, and the number of laminas in which they appear.
Building construction - Laminated
Laminated products
Panels - Tests
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Block shear testing of CLT panels : an exploratory study

https://library.fpinnovations.ca/en/permalink/fpipub2759
Author
Casilla, Romulo C.
Pirvu, Ciprian
Wang, Brad J.
Lum, Conroy
Date
April 2011
Edition
39375
Material Type
Research report
Field
Sustainable Construction
Author
Casilla, Romulo C.
Pirvu, Ciprian
Wang, Brad J.
Lum, Conroy
Date
April 2011
Edition
39375
Material Type
Research report
Physical Description
35 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Building Systems
Subject
Timber
Laminate product
Design
Building construction
Series Number
Transformative Technologies #TT1.07
W-2846
Location
Vancouver, British Columbia
Language
English
Abstract
A study was conducted with the primary objective of examining the efficacy of a standard block shear test method to assess the bond quality of cross-laminated timber (CLT) products. The secondary objective was to examine the effect of pressure and adhesive type on the block shear properties of CLT panels. The wood material used for the CLT samples was Select grade nominal 25 x 152-mm (1 x 6-inch) Hem-Fir. Three adhesive types were evaluated under two test conditions: dry and vacuum-pressure-dry (VPD), the latter as described in CSA standard O112.10. Shear strength and wood failure were evaluated for each test condition. Among the four properties evaluated (dry and VPD shear strength, and dry and VPD wood failure), only the VPD wood failure showed consistency in assessing the bond quality of the CLT panels in terms of the factors (pressure and adhesive type) evaluated. Adhesive type had a strong effect on VPD wood failure. The different performance levels of the three adhesives were useful in providing insights into how the VPD block shear wood failure test responds to significant changes in CLT manufacturing parameters. The pressure used in fabricating the CLT panels showed a strong effect on VPD wood failure as demonstrated for one of the adhesives. VPD wood failure decreased with decreasing pressure. Although dry shear wood failure was able to detect the effect of pressure, it failed to detect the effect of adhesive type on the bond quality of the CLT panels. These results provide support as to the effectiveness of the VPD block shear wood failure test in assessing the bond quality of CLT panels. The VPD conditioning treatment was able to identify poor bondline manufacturing conditions by observed changes in the mode of failure, which is also considered an indication of wood-adhesive bond durability. These results corroborate those obtained from the delamination test conducted in a previous study (Casilla et al. 2011). Along with the delamination test proposed in an earlier report, the VPD block shear wood failure can be used to assess the CLT bond quality. Although promising, more testing is needed to assess whether the VPD block shear wood failure can be used in lieu of the delamination test. The other properties studied (shear strength and dry wood failure), however, were not found to be useful in consistently assessing bond line manufacturing quality.
Building construction - Design
Cross-laminated timber
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Effect of adhesive cure on quality of fingerjoined lumber

https://library.fpinnovations.ca/en/permalink/fpipub39328
Author
Pirvu, Ciprian
Date
March 2011
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Pirvu, Ciprian
Contributor
Natural Resources Canada. Canadian Forest Service.
Date
March 2011
Material Type
Research report
Physical Description
45 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Joints
Series Number
Value to Wood No. FPI 121W
W-2809
Location
Vancouver, British Columbia
Language
English
Abstract
The relationship between proof load level of fingerjoined lumber and degree of cure of adhesive bonds was investigated. Tension tests were completed for two different degrees of cure for a single adhesive. The proof load level determined for the partially cured joints did not cause damage to the joints that survived the proof test. Preliminary guidelines for determining appropriate proof load levels for testing fingerjoined lumber with partially cured joints were proposed. The proposed guidelines will need to be validated through mill trials to demonstrate their efficacy and reliability to the manufacturer and third party inspection agency.
Fingerjoined lumber
Glued joints - Finger
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Delamination testing of CLT panels : an exploratory study

https://library.fpinnovations.ca/en/permalink/fpipub39330
Author
Casilla, Romulo C.
Pirvu, Ciprian
Wang, Brad J.
Date
February 2011
Material Type
Research report
Field
Sustainable Construction
Author
Casilla, Romulo C.
Pirvu, Ciprian
Wang, Brad J.
Date
February 2011
Material Type
Research report
Physical Description
44 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Building Systems
Subject
Timber
Mechanical properties
Laminate product
Gluing
Series Number
Transformative Technologies # TT1.07
W-2811
Location
Vancouver, British Columbia
Language
English
Abstract
A study was conducted with the primary objective of examining the efficacy of delamination test using cylindrical core specimens to assess the bond quality of cross laminated timber (CLT) products. A prototype coring drill bit was fabricated to prepare a cylindrical-shaped specimen, the height of which corresponds to the full thickness of the CLT panel. A secondary objective was to examine the effect of pressure, adhesive type, number of plies, and specimen shape on the delamination resistance of CLT panels. The wood material used for the CLT samples was Select grade nominal 1 x 6-inch Hem-Fir boards. Examples of three adhesive types were evaluated, which were designated as A, B, and C. The delamination tests used were as described in CAN / CSA O122-06 and EN 302-2. Cylindrical specimen extracted as core was found satisfactory as a test specimen type for use in delamination testing of CLT product. Its efficacy was comparable to that of a square cross-section specimen. The former is recommended as it can be extracted from thicker panels and from any location in the panel. It would also be more convenient to plug the round hole. Adhesive type had a strong effect on delamination resistance based on the two delamination tests used. Adhesive A exhibited the greatest delamination resistance, followed in decreasing order, by adhesives C and B. It should be noted that no effort was made to find the optimum CLT manufacturing parameters for each type of adhesive. Therefore the relative rankings of the adhesives tested may not be representative. However, for the purposes of this study, the different performance levels from the three adhesives are useful in providing insight into how the proposed delamination test responds to significant changes in CLT manufacturing parameters. Pressure used in fabricating the CLT panel showed a strong effect on delamination resistance as demonstrated for one of the adhesives. Delamination resistance decreased with decreasing pressure. The effect of the number of plies in the CLT panel was dependent upon the type of adhesive, and this was probably related to the adhesive’s assembly time characteristic. These results provide support as to the effectiveness of delamination test in assessing the moisture durability of CLT panels. It was able to differentiate the performance in delamination resistance among different types of adhesives, and able to detect the effect of manufacturing parameters such as pressure and increased number of plies in CLT construction. The test procedure described in CAN / CSA O122-06 appears to be reasonable in the delamination resistance assessment of CLT panels for qualification and quality control testing. Based on the results of the study along with some background information and guidelines, delamination requirements for CLT panels are proposed. The permitted delamination values are greater than those currently specified for laminated and fingerjoined lumber products. This is in recognition of the higher bond line stresses when bonded perpendicular laminations (i.e. CLT) are exposed to the delamination wetting and drying cycles, as opposed to parallel laminations (i.e. glulam or fingerjoints).
Cross-laminated timber
Laminated products - Gluing - Strength
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23 records – page 1 of 3.