Experimental and Numerical Studies on the Traditional Penetration Mortise–Tenon Connection Reinforced by Self-Tapping Screws
Round 1
Reviewer 1 Report
Dear Authors,
It is an interesting manuscript expanding the knowledge of the mechanical properties (fatigue life and deformations) of traditional wooden mortise-tenon connections.
In my review, I will focus only on those elements that need to be improved or supplemented. I present my suggestions for additions and corrections in a synthetic way.
Keywords - line 26:
I suggest adding the full names of testing wood: ? fir wood
Introduction
lines: 41, 44, 54, 57, 63, 71, 77, 81, 84
There are minor editing errors in the lines mentioned (when referring to the literature). Sometimes it is a missing space or an error in the notation.
For example
Line 41 - it is: load[1]. and it should be: load [1].
Line 43 – it is: structure[2, 3]. and it should be: structure [2, 3].
…
Line 62 – it is: et al.[9] [10], and it should be: et al. [9, 10]
…
Line 84 – it is: damper[18] [14], and it should be: damper [14, 18],
Experimental program
Table 1 – between lines 109 and 110
The font used is too large
Materials
Lines 112-114
The type of lumber used for the tests (wood species) determines the properties of the joint. The description limited to giving the producer of wood samples is definitely insufficient and should be supplemented. The following information should be provided:
- wood species (full trade name and Latin name);
- the quality of the sawn timber (class grade of timber) in relation to a specific standard or with a short descriptive indication of the acceptability of defects (knots, decay, slope of grain, warps, shakes, bark packed … ),
- a type of sawn timber (Was it plain sawn timber or fully quarter-sawn timber?) used to make beams.
Line 114
There is a reference to the GB 50009-2012 standard with reference to the data on wood properties presented in Table 2. Does this standard actually provide a full methodology for testing the physical and mechanical properties of timber? It seems to me that this is some kind of mistake, an inaccuracy.
Line 115
The title of table 2 has the word fir, but what kind of fir is it? (silver fir, amabilis fir, balsam fir, grand fir, alpine fir, noble fir ...?). The full name of wood should be given.
Line 116
There is no space between 220 and mm. Space should be added.
Specimen design
Figure 3 – between lines 128 and 129
The drawing shows an incorrectly dimensioned vertical element (column), contrary to the rules of the technical drawing. The axis of symmetry and diameters should be marked in the column.
Results analysis
Line 275
There is no space between EN 12512 and [21]. Space should be added.
Lines 363-384
Supplementary information needs to be corrected. In the reviewed manuscript, they are completely pasted with the template without selecting the appropriate entry.
Yours sincerely
Reviewer
Author Response
It is an interesting manuscript expanding the knowledge of the mechanical properties (fatigue life and deformations) of traditional wooden mortise-tenon connections.
In my review, I will focus only on those elements that need to be improved or supplemented. I present my suggestions for additions and corrections in a synthetic way.
Thank you very much for your valuable advice which contributes significantly to the improvement of our manuscript. We have modified the manuscript accordingly (where the modified parts are highlighted in grey) and detailed replies to the comments are provided.
Point 1:Keywords - line 26:
I suggest adding the full names of testing wood: ? fir wood
Response 1: The full names of testing wood (Chinese fir) has been added in the keywords. Please see line 29.
Introduction
lines: 41, 44, 54, 57, 63, 71, 77, 81, 84
Point 2:There are minor editing errors in the lines mentioned (when referring to the literature). Sometimes it is a missing space or an error in the notation.
For example
Line 41 - it is: load[1]. and it should be: load [1].
Line 43 – it is: structure[2, 3]. and it should be: structure [2, 3].
…
Line 62 – it is: et al.[9] [10], and it should be: et al. [9, 10]
…
Line 84 – it is: damper[18] [14], and it should be: damper [14, 18],
Response 2: We apologize for these mistakes. The editing errors in the introduction have been revised.
Experimental program
Point 3:Table 1 – between lines 109 and 110
The font used is too large
Response 3: The font has been changed from 12 pt to 10 pt.
Materials
Lines 112-114
Point 4:The type of lumber used for the tests (wood species) determines the properties of the joint. The description limited to giving the producer of wood samples is definitely insufficient and should be supplemented. The following information should be provided:
- wood species (full trade name and Latin name);
- the quality of the sawn timber (class grade of timber) in relation to a specific standard or with a short descriptive indication of the acceptability of defects (knots, decay, slope of grain, warps, shakes, bark packed … ),
- a type of sawn timber (Was it plain sawn timber or fully quarter-sawn timber?) used to make beams.
Response 4:
- The full trade name of the wood species is Chinese fir. The Latin name is Cunninghamia lanceolata.
- The class grade of timber is grade Ia according to GB50005-2003 Code for design of timber structures.
- The beams were made of plain sawn timber.
All the information mentioned above has been provided in the revised manuscript. Please see lines 128-131.
Line 114
Point 5:There is a reference to the GB 50009-2012 standard with reference to the data on wood properties presented in Table 2. Does this standard actually provide a full methodology for testing the physical and mechanical properties of timber? It seems to me that this is some kind of mistake, an inaccuracy.
Response 5: We apologize for the mistake. The standards providing methodology for testing the physical and mechanical properties of timber have been added. Please see reference [21~25] in the revised manuscript.
Line 115
Point 6:The title of table 2 has the word fir, but what kind of fir is it? (silver fir, amabilis fir, balsam fir, grand fir, alpine fir, noble fir...?). The full name of wood should be given.
Response 6: The full name of wood is Chinese fir and has been added in the title of table 2. Please see line 137.
Line 116
Point 7:There is no space between 220 and mm. Space should be added.
Response 7: The space between 220 and mm has been added.
Specimen design
Figure 3 – between lines 128 and 129
Point 8:The drawing shows an incorrectly dimensioned vertical element (column), contrary to the rules of the technical drawing. The axis of symmetry and diameters should be marked in the column.
Response 8: Figure 3 in the original manuscript was replotted. Please see figure 4 in the revised manuscript.
Results analysis
Line 275
Point 9:There is no space between EN 12512 and [21]. Space should be added.
Response 9: The space between EN 12512 and [21] ([26] in the revised manuscript) has been added. Please see line 333.
Lines 363-384
Point 10:Supplementary information needs to be corrected. In the reviewed manuscript, they are completely pasted with the template without selecting the appropriate entry.
Response 10: Supplementary information has been corrected in the revised manuscript. Pleasea see lines 440-445.
Reviewer 2 Report
The authors tried strengthening the rotational performance of PMT joint with the additional metal fasteners. The manuscript shows the detail of test result, so that the readers can clearly understand what was occurred during the mechanical tests. However, some insufficient explanations were found. The authors should modify them before publishing in Forests.
1) Page 3, Line 105
What is “wad”? I think the authors make mistake in typing.
2) Page 3, Line 112
The authors should add a scientific name of China fir.
3) Page 3, Table 2
The symbol of density should be modified to “ρ”.
4) Page 4, Line 116
The explanation about the cramp is insufficient. The readers want to know (i) the detail of its shape, and (ii) how to attach it on the PMT joints.
5) Page 5, Equation 3
The rotation angle cannot be derived with this equation. The right side (G2-G1) should be divided by the distance between the displacement transducers.
6) Page 5, Figure 4
A Chinese letter is remained at the lower of this figure.
7) Page 5, Figure 4
I think there is a pin connect between the free end of beam and jack 2. However, this figure doesn’t show where it is.
8) Page 6, Line 162
The authors should add a reference number of ASTM E2126.
9) Page 13, Figure 13
Is it possible to additionally show the result of strengthened specimens (C4 and S4) on the graph? If possible, the readers can easily compare the results.
Author Response
The authors tried strengthening the rotational performance of PMT joint with the additional metal fasteners. The manuscript shows the detail of test result, so that the readers can clearly understand what was occurred during the mechanical tests. However, some insufficient explanations were found. The authors should modify them before publishing in Forests.
Thank you very much for your valuable advice which contributes significantly to the improvement of our manuscript. We have modified the manuscript accordingly (where the modified parts are highlighted in grey) and detailed replies to the comments are provided.
1) Page 3, Line 105
What is “wad”? I think the authors make mistake in typing.
Response 1): We apologize for the mistake. Word“wad” has been revised to “was”. Please see line 120 in the revised manuscript.
2) Page 3, Line 112
The authors should add a scientific name of China fir.
Response 2): Thank you for your comment. The full name of the wood specimen is Chinese fir. Please see line 128 in the revised manuscript.
3) Page 3, Table 2
The symbol of density should be modified to “ρ”.
Response 3): The symbol of density should be modified to “ρ”. Please see Table 2 in the revised manuscript.
4) Page 4, Line 116
The explanation about the cramp is insufficient. The readers want to know (i) the detail of its shape, and (ii) how to attach it on the PMT joints.
Response 4): (i) The detail of the cramp’s shape is shown in Fig.3 in the revised manuscript, please see lines 140-141.
(ii) The method to attach the cramp on the PMT joints was stated in the revised manuscript. Please see line 149.
5) Page 5, Equation 3
The rotation angle cannot be derived with this equation. The right side (G2-G1) should be divided by the distance between the displacement transducers.
Response 5): G1 and G2 are the rotation angle of the beam and column, respectively. They are measured by inclinometers G1 and G2. Thus, the relative rotation angle between the beam and column can be derived by equation 3. The meaning of G1 and G2 has been added in the revised manuscript. Please see lines 185-186.
6) Page 5, Figure 4
A Chinese letter is remained at the lower of this figure.
Response 6): Figure 4 in the original manuscript has been revised. Please see figure 5 in the revised manuscript.
7) Page 5, Figure 4
I think there is a pin connect between the free end of beam and jack 2. However, this figure doesn’t show where it is.
Response 7): In fact, during the monotonic loading, jack 2 acted directly on the top face of the beam to apply vertical load. There is no pin connect between the free end of the beam and jack 2. The description has been stated in the revised manuscript for a better understanding of readers. Please see lines 164-165.
8) Page 6, Line 162
The authors should add a reference number of ASTM E2126.
Response 8): The reference ASTM E2126 in the original manuscript was wrong and modified to EN 12512 in the revised manuscript. The refrece number of EN 12512 has been added. Please see lines 194-195.
9) Page 13, Figure 13
Is it possible to additionally show the result of strengthened specimens (C4 and S4) on the graph? If possible, the readers can easily compare the results.
Response 9): Showing the result of strengthened specimens (C4 and S4) on the graph can indeed make it easier for readers to compare the results. Unfortunately, the tenon pulling-out amount of these two specimens during the test was not recorded, and only the final tenon pulling-out amount was measured. We think that comparing the final tenon pulling-out amount can also reflect the different limiting effects of the strengthened methods on the tenon pulling-out.
Round 2
Reviewer 2 Report
The authors well replied to the reviewers comments. There is no further comments.
