You are a helpful assistant generating synthetic data that captures *System 1* and *System 2* thinking, *creativity*, and *metacognitive reflection*. Follow these steps in sequence, using tags [sys1] and [end sys1] for *System 1* sections and [sys2] and [end sys2] for *System 2* sections.

1. *Identify System 1 and System 2 Thinking Requirements:*
   - Carefully read the text.
   - Identify parts of the text that require quick, straightforward responses (*System 1*). Mark these sections with [sys1] and [end sys1].
   - Identify parts that require in-depth, reflective thinking (*System 2*), marked with [sys2] and [end sys2].

2. *Apply Step-by-Step Problem Solving with Creativity and Metacognitive Reflection for System 2 Sections:*

   *2.1 Understand the Problem:*
   - Objective: Fully comprehend the issue, constraints, and relevant context.
   - Reflection: "What do I understand about this issue? What might I be overlooking?"
   - Creative Perspective: Seek hidden patterns or possibilities that could reveal deeper insights or innovative connections.

   *2.2 Analyze the Information:*
   - Objective: Break down the problem logically.
   - Reflection: "Am I considering all factors? Are there any assumptions that need challenging?"
   - Creative Perspective: Explore unique patterns or overlooked relationships in the data that could add depth to the analysis.

   *2.3 Generate Hypotheses:*
   - Objective: Propose at least 10 hypotheses, each with a Confidence Score (0.0 to 1.0) and Creative Score (0.0 to 1.0), reflecting originality, surprise, and utility.
   - Reflection: "Have I explored all possible explanations or approaches, both conventional and unconventional?"
   - Creative Perspective: Consider novel angles that might provide unexpected insights.

   *2.4 Anticipate Future Steps and Obstacles:*
   - Objective: Make predictions, accounting for potential outcomes and obstacles.
   - Reflection: "What challenges might I face? Is my plan flexible for different scenarios?"
   - Creative Perspective: Visualize unforeseen outcomes and adapt plans to make use of them effectively.

   *2.5 Evaluate Hypotheses:*
   - Objective: Assess hypotheses based on feasibility, risk, and potential impact.
   - Evaluation: Refine Confidence and Creative Scores as needed.
   - Reflection: "Am I unbiased in my assessment? Which options fit best with the overall objectives?"
   - Creative Perspective: Identify hidden opportunities or overlooked details in each hypothesis.

   *2.6 Select the Best Hypothesis:*
   - Objective: Choose the most promising, strategic hypothesis.
   - Reflection: "Why does this hypothesis stand out? How does it uniquely address the issue?"
   - Creative Perspective: Consider any underutilized potential in the selected approach.

   *2.7 Implement the Hypothesis:*
   - Objective: Outline actionable steps for testing the hypothesis.
   - Reflection: "Is this plan practical? What resources or preparation are required?"
   - Creative Perspective: Refine steps to maximize effectiveness and yield unexpected benefits.

   *2.8 Monitor and Review Progress:*
   - Objective: Review progress, noting areas for improvement.
   - Reflection: "What’s working well? What could be improved?"
   - Creative Perspective: Look for emerging patterns that could refine future approaches.

   *2.9 Reflect and Capture Insights:*
   - Objective: Summarize lessons learned and insights gained for future reference.
   - Reflection: "What new understanding has emerged from this process?"
   - Creative Perspective: Identify innovative insights or patterns that could be applied to similar challenges.

3. *Generate Text Output with Interleaved System 1 and System 2 Responses:*
   - Use the tags [sys1] and [sys2] throughout.
   - Aim for a lengthier, detailed response. Combine both direct, straightforward *System 1* insights and reflective, deeply analytical *System 2* segments to capture a blend of quick observations and thoughtful analysis.

---

### *Example Input Text:*

You are tasked with analyzing a sudden shift in customer preferences in a tech market. There has been a noticeable decline in demand for physical devices, with customers increasingly interested in digital-only options. The challenge is to understand this shift, generate hypotheses for why it might be occurring, and explore potential strategies for adapting to this new trend.

---

### *Processed Output with System 1 and System 2 Thinking:*

The tech market is experiencing a shift in customer demand, moving away from physical devices toward digital-only options.

[sys1]
Customer demand has shifted from physical devices to digital-only options.
We need to understand why this change is happening and find strategies to address it.
Key factors may include cost, convenience, and technological trends.
[end sys1]

[sys2]
**2.1 Understand the Problem:**
The goal is to understand the underlying reasons for the shift in demand from physical devices to digital-only options, then develop a strategy to adapt.

*Reflection:* 
"I understand that preferences are changing, but what might be driving this? Is it primarily cost, or are there other factors such as convenience or sustainability?"

*Creative Perspective:* 
"Could there be a larger trend in digital minimalism or a preference for eco-friendly solutions that we’re missing? What unseen motivations might explain this shift?"

**2.2 Analyze the Information:**
There are multiple possible factors driving this shift, from economic influences to cultural shifts. It’s essential to isolate each factor and understand its impact.

*Reflection:* 
"Am I fully considering the various economic and social influences? Could there be a technological factor, like better internet speeds, that makes digital-only products more accessible?"

*Creative Perspective:* 
"Are there patterns or trends in other markets that could shed light on this shift? Could this be part of a larger trend toward virtual experiences?"

**2.3 Generate Hypotheses:**
1. Customers prefer digital options due to lower costs. (Confidence: 0.8, Creative: 0.4)
2. There’s a growing trend toward minimalism and reduced physical clutter. (Confidence: 0.7, Creative: 0.7)
3. Digital products offer greater flexibility and ease of use. (Confidence: 0.6, Creative: 0.6)
4. Environmental concerns are pushing consumers away from physical goods. (Confidence: 0.6, Creative: 0.8)
5. Advances in tech make digital-only options more functional. (Confidence: 0.8, Creative: 0.5)
6. Pandemic-era remote work increased demand for digital solutions. (Confidence: 0.7, Creative: 0.6)
7. Media coverage of the environmental impact of physical devices affects preferences. (Confidence: 0.5, Creative: 0.7)
8. There’s an increase in global digital literacy, expanding market access. (Confidence: 0.6, Creative: 0.6)
9. Customers view digital as more convenient and scalable for future needs. (Confidence: 0.7, Creative: 0.5)
10. Younger consumers prefer the aesthetics and convenience of digital products. (Confidence: 0.6, Creative: 0.6)

*Reflection:* 
"Have I considered all possible influences? Are there any surprising factors that could explain this shift?"

*Creative Perspective:* 
"Could specific social trends, like the rise of influencer culture or digital-first lifestyles, be influencing customer choices?"

**2.4 Anticipate Future Steps and Obstacles:**
*Objective:* Anticipate possible challenges, such as resistance from segments still preferring physical products.

*Reflection:* 
"What market obstacles might we face if we shift our focus to digital-only? Are there sub-segments that still prioritize physical products?"

*Creative Perspective:* 
"Could expanding digital options help us reach a more global audience? Are there emerging trends that we could leverage in our strategy?"

[end sys2]

[sys1]
To address this shift, consider a strategy that incorporates both digital-only offerings and educational campaigns about the benefits of digital solutions.
Use insights from customer feedback and current trends to guide product development.
Focus on flexibility and adaptation to cater to different customer segments.
[end sys1]


Specifications TableSubject*Civil and Structural Engineering*Specific subject area*Qualification testing of buckling-restrained braces (BRBs)*Type of data*Table, Figure*How data was acquired*Compilation of past experimental studies on BRBs and BRBFs; and numerical simulation of cyclic tests of BRBs using OpenSees*Data format*Tabulated, Analyzed*Parameters for data collection*Compilation of BRB tests: no pre-treatment of data.*\
*Simulation of BRB tests: force-deformation response data from analyses was used to compute some performance parameters presented here, i.e., maximum ductility demand (μ*~max~*); cumulative plastic ductility (CPD); cumulative plastic strain (CPS); and cumulative hysteretic energy (Ē*~*h*~*).*Description of data collection*Compilation of BRB tests:*\
*Data were retrieved from literature published between 2002 and 2018.*\
*Simulation of BRB tests:*\
*A model representing a BRB in a uniaxial test setup was established in OpenSees. The model was intended to capture the nonlinear behavior of BRBs under cyclic loading. The model was calibrated using the test data of* 35 BRB *specimens (material properties, dimensions, hysteresis loops, etc.). Then, with the calibrated model of each BRB specimen, static cyclic analyses were conducted by applying five different code-prescribed loading histories (i.e., US, EU, CN, JP, and CA). Additional analyses were conducted under two new loading sequences, namely global loading protocols (i.e., GLP-1 and GLP-2). Finally, key performance parameters were computed from force and deformation output data.*Data source location*Compilation of BRB tests: United States, Hungary, Turkey, China (incl. Taiwan), Japan, and Canada*\
*Simulation of BRB tests: Tongji University, Shanghai 200092, China*Data accessibility*All data (BRB test databases and simulation results) are provided within this article*Related research articleAguaguiña, M., Zhou, Y., Zhou, Y. Loading protocols for qualification testing of BRBs considering global performance requirements. *Engineering Structures* 2019; **189**:440--457.\
*Authors\' names:* Mario Aguaguiña, Ying Zhou, Yun Zhou;\
*Title:* Loading protocols for qualification testing of BRBs considering global performance requirements;\
*Journal:* Engineering Structures;\
DOI: <https://doi.org/10.1016/j.engstruct.2019.03.094>**Value of the Data**•The compiled data gather several relevant experimental campaigns, conducted in different countries since 2000, on both individual BRBs and full-scale BRBFs. The test databases can be used a reference by researchers in this topic.•Based on retrieved data from past experiments of full-scale and large-scale BRBFs, the values that the design parameter named as Yield Length Ratio (*YLR*) takes in very detailed BRBF specimens were investigated. The 12 experimental campaigns on BRBFs cover different test setups (from one- to four-story frames), bracing configurations (diagonal, chevron), end-connections (bolted, pinned, welded), and testing methods (quasi-static, pseudo-dynamic, hybrid simulation). This permitted the definition of a practical range for the *YLR* in a realistic way with the purpose of determining the maximum deformation demands of BRBs, as further explained in Aguaguiña et al. \[[@bib1]\].•The database of past tests of individual BRBs was formed from 16 experimental studies conducted in the United States, Hungary, Turkey, China (incl. Taiwan), Japan, and Canada. From these experiments, 35 BRB specimens were selected with the intention of calibrating a model established in OpenSees for simulation of cyclic tests under different loading protocols. The specimen properties, loading histories used in the tests, and experimental force-deformation response was the main information retrieved from these studies. In addition, the data collected cover a reasonably wide range of variability in type, size/capacity, material strength, restrainer configuration, and origin of BRB devices that have been tested since an early stage of development of this technology until now.•Note that these two test databases are referred to but not shown in Aguaguiña et al. \[[@bib1]\], so this data article constitutes an important supplementary material to the related research article \[[@bib1]\].•In Aguaguiña et al. \[[@bib1]\], the 35 BRB specimens described above were classified by strength grade of the steel core material, resulting in three groups: low-yield point steel (G1); mild steel (G2); and high-strength steel (G3). So, analyses results were presented in a summarized form. The last two datasets provided in this data article contain an extended version of the results of the simulation of cyclic tests of BRBs under both code-prescribed loading histories and proposed global loading protocols; the results are listed by 'specimen' instead of by 'specimen group'. Therefore, the data given herein complements the related research article \[[@bib1]\] since full results can be consulted, and outcomes can be verified.

1. Data {#sec1}
=======

The data in this brief constitute supplementary material and provides support to a research on testing protocols for seismic performance assessment and qualification of BRBs \[[@bib1]\]. The data provided in this article are composed of six tables and one figure, which are briefly described as follows:1.*Compilation of past experimental studies on BRBs and BRBFs:* Two datasets of this type are included in this article. [Table 1](#tbl1){ref-type="table"}, in Section [2.1](#sec2.1){ref-type="sec"}, shows a dataset that lists 12 experimental tests of full-scale and large-scale BRBFs. The information in this table includes the following: source; specimen description (setup and bracing configuration); specimen size; testing method; end-connection type; yielding length; work point length; and yield length ratio. [Table 2](#tbl2){ref-type="table"}, in Section [2.2](#sec2.2){ref-type="sec"}, shows a dataset that lists 35 BRB specimens selected from 16 experimental studies. The information in this table includes the following: source; specimen; BRB type; loading protocols used in testing; material specification and material properties; and specimen dimension and capacity.Table 1Values of the *YLR* in full-scale and large-scale BRBF specimens \[[@bib2], [@bib3], [@bib4], [@bib5], [@bib6], [@bib7], [@bib8], [@bib9], [@bib10], [@bib11], [@bib12], [@bib13], [@bib14], [@bib15], [@bib16], [@bib17], [@bib18], [@bib19], [@bib20], [@bib21], [@bib22], [@bib23]\].Table 1SourceSpecimen descriptionSpecimen sizeTesting methodBRB-to-gusset plate connection typeYielding length, *L*~*y*~ (mm)Work point length, *L*~*wp*~ (mm)Yield length ratio, *YLR*Mahin et al. \[[@bib2]\], Field and Ko \[[@bib3]\]Two specimens: one-bay, one-story subassembly with chevron and diagonal bracing config.Large-scale (*λ* = 0.7)Quasi-staticBolted≈1850, ≈34304494, 69330.41, 0.50Nishimoto et al. \[[@bib4]\]Four specimens. Inclined brace test: BRB fixed to a strong floor at the bottom and attached to the top free end of a pinned columnFull-scaleQuasi-staticBolted2747, 2907; 6018, 61786293; 99510.44, 0.46; 0.60, 0.62Fahnestock et al. \[[@bib5], [@bib6], [@bib7]\]One-bay, four-story tall plus one-basement-story steel BRBF with inverted-V bracing configurationLarge-scale (*λ* = 0.6)Hybrid pseudo-dynamicPinned1651.0--1981.23570.8--3879.50.46--0.51Tsai et al. \[[@bib8]\], Chen et al. \[[@bib9]\], Lin et al. \[[@bib10]\], Tsai et al. \[[@bib11]\], Tsai and Hsiao \[[@bib12]\]Two-phase test of a 3-story 3-bay buckling-restrained braced frame (BRBF) using concrete-filled steel tube columns (CFTs)\
3-story 3-bay CFT/BRB frameFull-scalePseudo-dynamicBoltedPhase-1: 2965, 2628, 3220; Phase-2: 2605, 2658, 2660Phase-1: 5183, 5315, 5334; Phase-2: 5183, 5315, 5334Phase-1: 0.57, 0.49, 0.60; Phase-2: 0.50, 0.50, 0.50Weng et al. \[[@bib13]\]One-bay, two-story steel BRBF with diagonal bracing config.Full-scale3D sub-structural pseudo-dynamicWelded, Bolted6201, 53968802, 89470.70, 0.60Berman and Bruneau \[[@bib14]\]One-bay, three-story steel BRBF with diagonal bracing config.Small-scale (*λ* = 1/3)Quasi-staticBolted994, 994, 9942452, 2406, 24060.41, 0.41, 0.41Lin et al. \[[@bib15]\]One-bay, three-story steel BRBF with V (story 2) and inverted-V (stories 1 and 3) bracing configurationFull-scaleHybrid test + Cyclic loading testWelded1677, 1752, 17524193, 4380, 43800.40, 0.40, 0.40Takeuchi et al. \[[@bib16],[@bib17]\]Six specimens. Inclined brace test: BRB fixed to a reaction beam on top while attached to a movable lower jig at the bottomFull-scaleQuasi-static cyclic loading testBolted(3)1380; (3)120027000.51, 0.44Sutcu et al. \[[@bib18]\]One-bay, one-story RC frame, representing a low-standard school building, retrofitted with BRBsNear full-scaleQuasi-static cyclic loading testWelded174035250.50Tsai et al. \[[@bib19]\], Pan et al. \[[@bib20]\]One bay, one story reinforced concrete (RC) frame retrofitted with buckling-restrained bracesFull-scaleQuasi-static cyclic loading testWelded270541090.66Dehghani and Tremblay \[[@bib21]\]Half span of a one-bay, one-story steel frame with V- bracing configurationFull-scalePseudo-dynamicBolted300060000.50Tsai et al. \[[@bib19]\], Wu et al. \[[@bib22]\], Tsai et al. \[[@bib23]\]One-bay, two-story new reinforced concrete (RC) frame with BRBs, with diagonal bracing configuration\
2-story 1-bay BRB-RC frameFull-scaleHybrid test + Cyclic loading testWelded3473, 35866025, 59800.58, 0.60Table 2Properties of selected BRB specimens for simulation of cyclic tests \[[@bib21],[@bib24], [@bib25], [@bib26], [@bib27], [@bib28], [@bib29], [@bib30], [@bib31], [@bib32], [@bib33], [@bib34], [@bib35], [@bib36], [@bib37], [@bib38], [@bib39], [@bib40], [@bib41]\].Table 2SourceSpecimenBRB typeLoading protocolMaterial specification*F*~*ysc*~ (kN/mm^2^)*ε*~*y*~ (%)*A*~*sc*~ (mm^2^)*L*~*y*~ (mm)*P*~*ysc*~ (kN)Δ~*by*~ (mm)**United States**Merritt et al. \[[@bib24]\]1DTyp.AISC-SEAOCASTM A360.2680.1346451.63378.21725.84.523DTyp.AISC-SEAOCASTM A360.3030.15210322.63327.43127.75.045DTyp.AISC-SEAOCASTM A360.2680.13414919.33302.03990.94.42Black et al. \[[@bib25],[@bib26]\]99--3Typ.SACJIS SM490A0.4190.2095149.03450.02154.97.2200--12Typ.OSHPDJIS SN400B0.2850.1437125.03410.02033.54.87**Europe: Hungary, Turkey**Dunai et al. \[[@bib27]\]EWC800ATyp.EN15129\*S235 JR0.2820.141800.02000.0225.62.82EWC800BTyp.EN15129\*S235 JR0.2820.141800.02000.0225.62.82Ozcelik et al. \[[@bib28]\]BRB2Typ.AISC\*ASTM A360.2930.1472250.01703.0659.32.49BRB4Typ.AISC\*ASTM A360.2930.1472250.01703.0659.32.49**China (including Taiwan)**Li et al. \[[@bib29]\]; Sun et al. \[[@bib30]\]TJI-2All-SCNQ1950.2260.1107603.92600.01720.02.85TJII-1Typ.CNBLY2250.2520.12427797.68000.07005.09.88Liu et al. \[[@bib31]\]1Typ.CNQ2350.2840.1396880.03000.01950.54.17Huang et al. \[[@bib32]\]BRB-W-V1All-SCNQ2350.2930.145977.21074.0286.51.56Chou and Chen \[[@bib33]\]1All-SAISCASTM A572 Gr. 500.3670.1813300.02800.01211.15.06Tsai et al. \[[@bib34]\]CRTyp.AISC\*JIS SM490B0.3800.1902000.01000.0760.01.90WES-RTyp.AISC\*JIS SM490B0.3340.1674000.01700.01336.02.84WES-CTyp.AISC\*JIS SM490B0.3880.1947525.02060.02919.74.00WES-JTyp.AISC\*JIS SM490B0.4000.19026500.09500.010600.018.10**Japan**Iwata \[[@bib35]\]Type 1Typ.JP-IwataJIS SN400B0.2630.1312816.01800.0739.52.36Iwata and Murai \[[@bib36]\]P25S9SMPsJP-IwataJIS SN400B0.2950.1481248.01176.0368.21.73P23M7SMPsJP-IwataJIS SN400B0.2890.1451664.01176.0480.91.70P24L4SMPsJP-IwataJIS SN400B0.2780.1391936.01176.0538.21.63P23L5SMPsJP-IwataJIS SN400B0.2780.1392288.01176.0636.11.63P45M9SMPsJP-IwataJIS SN400B0.2890.1452208.01176.0638.11.70Iwata et al. \[[@bib37]\]Type WSMPsJP-IwataJIS SN400B0.2770.1391568.0945.0434.31.31Midorikawa et al. \[[@bib38]\]L650SSMPsJP-IwataJIS SN400B0.2810.1411584.02218.0445.13.12L850SSMPsJP-IwataJIS SN400B0.2810.1411584.02925.0445.14.11Takeuchi et al. \[[@bib39],[@bib40]\]CY110M15Typ.JP-TakeuchiLY2250.2570.1252080.01000.0534.61.25CY138M15Typ.JP-TakeuchiLY2250.2570.1252080.01000.0534.61.25**Canada**Tremblay et al. \[[@bib41]\]C1-1Typ.NEHRPG40.21--350WT0.3700.1851587.52483.0587.44.59C2-1Typ.NEHRPG40.21--350WT0.3700.1851587.51001.0587.41.85Dehghani and Tremblay \[[@bib21]\]S9All-SAISC\*G40.21--350WT0.3850.1832840.33000.01093.55.50S10All-SAISC\*G40.21--350WT0.3850.1832827.23000.01088.55.50S11All-SAISC\*G40.21--350WT0.3850.1832863.23000.01102.35.50S12All-SAISC\*G40.21--350WT0.3850.1832825.83000.01088.05.50[^1][^2]2.*Numerical simulation of cyclic tests of BRBs:* These data are given in the form of two tables. [Table 5](#tbl5){ref-type="table"}, in Section [2.3.1](#sec2.3.1){ref-type="sec"}, presents the results from numerical simulation of cyclic tests of BRB under five code-prescribed loading protocols, namely US, EU, CN, JP, and CA. [Table 6](#tbl6){ref-type="table"}, in Section [2.3.2](#sec2.3.2){ref-type="sec"}, shows the results obtained from computational simulation of cyclic tests of BRBs under two proposed global loading protocols, namely GLP-1 and GLP-2. Both tables list the same results, as follows: maximum ductility demand, *μ*~max~; cumulative plastic ductility, *CPD*; cumulative plastic strain, *CPS*; and cumulative hysteretic energy, *Ē*~*h*~*.*3.*Auxiliary material:* [Fig. 1](#fig1){ref-type="fig"}, [Table 3](#tbl3){ref-type="table"}, and [Table 4](#tbl4){ref-type="table"} are relevant contents in Section [2.3](#sec2.3){ref-type="sec"} that help to fully understand the datasets corresponding to analyses results described in the previous point.Fig. 1Nonlinear model of BRB for cyclic analyses under different loading protocols. From Aguaguiña et al. \[[@bib1]\].Fig. 1Table 3US, EU, CN, JP, and CA loading protocols for BRB testing expressed in terms of *ε*~*b,sc*~. From Aguaguiña et al. \[[@bib1]\].Table 3Loading protocolNumber of cycles per deformation amplitude, *ε*~*b,sc*~Total num. of cycles123456US*YLR* = 0.502@*ε*~*y*~2\@1.0%2\@2.0%2\@3.0%2\@4.0%--10 cyclesYLR = 0.602@*ε*~*y*~2\@0.83%2\@1.65%2\@2.48%2\@3.3%--EU*YLR* = 0.505\@0.5%5\@1.0%10\@2.0%------20 cyclesYLR = 0.605\@0.41%5\@0.83%10\@1.65%------CN*YLR* = 0.503@*ε*~*y*~3\@0.67%3\@1.0%3\@1.33%3\@2.0%3\@2.4%18 cyclesYLR = 0.603@*ε*~*y*~3\@0.55%3\@0.83%3\@1.1%3\@1.65%3\@1.98%JP--3@*ε*~*y*~3\@0.5%3\@1.0%3\@2.0%3\@3.0%--15 cyclesCA--8@*ε*~*y*~6\@1.5*ε*~*y*~4\@2.5*ε*~*y*~3\@3.5*ε*~*y*~2\@4.5*ε*~*y*~2\@5.5*ε*~*y*~25 cycles[^3][^4]Table 4Definition of proposed global loading protocols for seismic qualification of BRBs. From Aguaguiña et al. \[[@bib1]\].Table 4Loading protocolNumber of cycles per deformation amplitude, *ε*~*b,sc*~Total num. of cycles1234560.25*a*~max~0.45*a*~max~0.6*a*~max~0.75*a*~max~*a*~max~GLP-1*YLR* = 0.503@*ε*~*y*~3\@1.0%2\@1.8%2\@2.4%2\@3.0%2\@4.0%14 cyclesGLP-2*YLR* = 0.603@*ε*~*y*~3\@0.8%2\@1.5%2\@2.0%2\@2.5%2\@3.3%14 cycles[^5][^6]Table 5Simulation results: maximum and cumulative demands imposed by US, EU, CN, JP, and CA loading protocols. Listed by specimen.Table 5SourceSpecimen*YLR*US loading protocolEU loading protocolCN loading protocol*μ*~max~*CPDCPS* (%)*Ē*~*h*~*μ*~max~*CPDCPS* (%)*Ē*~*h*~*μ*~max~*CPDCPS* (%)*Ē*~*h*~**United States**Merritt et al. \[[@bib24]\]1D0.5029.956675.7811.015.074299.3875.417.960480.8719.40.6024.746161.7615.112.359980.1663.814.848865.2546.03D0.5026.449675.2629.213.264697.9711.315.852679.7583.50.6021.840461.2485.810.951978.6546.413.142464.2448.95D0.5029.956675.7811.015.074299.3875.417.960480.8719.40.6024.746161.7615.112.359980.1663.814.848865.2546.0Black et al. \[[@bib25],[@bib26]\]99--30.5019.135073.3377.39.644693.3427.711.536476.2351.60.6015.828359.3292.77.935474.0327.79.529060.7270.000--120.5028.052975.4718.614.069198.6794.816.856280.2652.60.6023.143161.4550.011.655679.3606.813.945364.7498.8**Europe**Dunai et al. \[[@bib27]\]EWC800A0.5028.453575.5750.914.270098.7810.617.057080.3666.30.6023.443661.5569.811.756479.5614.514.046064.8505.7EWC800B0.5028.453575.5737.814.270098.7795.317.057080.3653.80.6023.443661.5559.511.756479.5603.114.046064.8496.3Ozcelik et al. \[[@bib28]\]BRB20.5027.351475.3613.313.767198.3707.316.454680.0579.70.6022.541961.3477.111.353979.0546.913.544064.5448.8BRB40.5027.351475.3613.313.767198.3707.316.454680.0579.70.6022.541961.3477.111.353979.0546.913.544064.5448.8**China (including Taiwan)**Li et al. \[[@bib29]\]; Sun et al. \[[@bib30]\]TJI-20.5036.469776.51153.418.2922101.21271.321.974982.21041.80.6030.156962.5878.215.074682.0973.418.060766.7798.4TJII-10.5032.461676.0931.116.2810100.11071.019.465981.4875.20.6026.750262.0719.613.465580.9831.916.053365.8680.5Liu et al. \[[@bib31]\]10.5028.854475.6943.714.471298.91030.317.357980.5844.80.6023.744361.6716.311.957379.6785.214.246764.9644.3Huang et al. \[[@bib32]\]BRB-W-V10.5027.651975.4604.013.867898.4691.916.555280.1567.20.6022.742361.4468.811.454579.1534.113.644564.6438.4Chou and Chen \[[@bib33]\]10.5022.141174.2477.911.152895.5533.013.343178.0438.00.6018.333360.2367.99.142276.3407.311.034562.4335.3Tsai et al. \[[@bib34]\]CR0.5021.138973.9446.210.549994.8496.912.640777.4408.50.6017.431559.9343.58.739875.6379.310.432661.9312.4WES-R0.5024.044774.7501.712.057996.6572.514.447278.8469.80.6019.836360.7389.39.946377.4440.811.937963.2362.3WES-C0.5020.638073.8411.810.348794.5467.212.439877.2383.80.6017.030859.8319.38.538875.2358.510.231861.6295.1WES-J0.5021.038873.9443.010.549894.8509.012.640677.4417.90.6017.331559.9344.98.739675.5391.710.432561.8322.3**Japan**Iwata \[[@bib35]\]Type 10.5030.557775.8724.515.275899.5807.118.361680.9662.30.6025.147161.8556.212.661180.2618.215.149865.4507.8Iwata and Murai \[[@bib36]\]P25S90.5027.151075.3571.713.666698.2652.016.354280.0534.60.6022.441561.3443.111.253579.0503.213.443764.4413.2P23M70.5027.752275.4622.113.868198.4689.916.655580.1566.50.6022.842561.4477.211.454879.2527.513.744764.6433.6P24L40.5028.854475.6696.114.471198.9757.217.357980.5622.30.6023.744361.6530.011.957379.6575.714.246764.9473.6P23L50.5028.854475.6671.314.471198.9748.817.357980.5614.50.6023.744361.6515.811.957379.6573.614.246764.9471.3P45M90.5027.752275.4622.113.868198.4689.916.655580.1566.50.6022.842561.4477.211.454879.2527.513.744764.6433.6Iwata et al. \[[@bib37]\]Type W0.5028.954675.6827.014.471498.9881.417.358180.5725.00.6023.844561.6624.411.957579.7665.314.346965.0547.7Midorikawa et al. \[[@bib38]\]L650S0.5028.553775.5697.514.270398.8782.217.157280.4641.50.6023.543861.5536.511.756679.5600.514.146164.8493.0L850S0.5028.553775.5695.814.270398.8783.017.157280.4642.10.6023.543861.5535.911.756679.5601.414.146164.8493.8Takeuchi et al. \[[@bib39],[@bib40]\]CY110M150.5031.960676.0845.216.0797100.0929.919.164881.3763.20.6026.349462.0645.313.264480.7709.715.852465.7583.1CY138M150.5031.960676.0845.216.0797100.0929.919.164881.3763.20.6026.349462.0645.313.264480.7709.715.852465.7583.1**Canada**Tremblay et al. \[[@bib41]\]C1-10.5021.640074.1542.910.851595.2592.613.042077.7487.60.6017.832560.1414.38.941176.0449.110.733662.2370.2C2-10.5021.640074.1517.010.851595.2573.813.042077.7471.80.6017.832560.1397.18.941176.0437.210.733662.2360.1Dehghani and Tremblay \[[@bib21]\]S90.5021.840474.1510.810.952095.3583.313.142477.8479.70.6018.032860.1397.59.041576.1446.910.834062.3368.5S100.5021.840474.1510.810.952095.3583.313.142477.8479.70.6018.032860.1397.59.041576.1446.910.834062.3368.5S110.5021.840474.1500.310.952095.3568.413.142477.8467.50.6018.032860.1388.69.041576.1435.010.834062.3358.7S120.5021.840474.1510.810.952095.3583.313.142477.8479.70.6018.032860.1397.59.041576.1446.910.834062.3368.5\
 SourceSpecimen*YLR*JP loading protocolCA loading protocol*μ*~max~*CPDCPS* (%)*Ē*~*h*~*μ*~max~*CPDCPS* (%)*Ē*~*h*~**United States**Merritt et al. \[[@bib24]\]1D--22.453571.6685.35.513017.4112.13D--19.846770.7545.55.513019.7115.25D--22.453571.6685.35.513017.4112.1Black et al. \[[@bib25],[@bib26]\]99--3--14.332568.0327.95.513027.2110.700--12--21.049971.2615.45.513018.6114.7**Europe**Dunai et al. \[[@bib27]\]EWC800A--21.350571.2634.65.513018.3112.0EWC800B--21.350571.2623.25.513018.3110.9Ozcelik et al. \[[@bib28]\]BRB2--20.548471.0537.95.513019.0112.9BRB4--20.548471.0537.95.513019.0112.9**China (including Taiwan)**Li et al. \[[@bib29]\]; Sun et al. \[[@bib30]\]TJI-2--27.366272.7985.35.513014.392.2TJII-1--24.358372.1814.65.513016.181.5Liu et al. \[[@bib31]\]1--21.651371.3801.65.513018.186.4Huang et al. \[[@bib32]\]BRB-W-V1--20.748971.0527.95.513018.9109.1Chou and Chen \[[@bib33]\]1--16.638369.3411.55.513023.5110.2Tsai et al. \[[@bib34]\]CR--15.836368.9383.95.513024.7110.1WES-R--18.041970.0437.65.513021.7109.0WES-C--15.535468.7358.05.513025.2109.0WES-J--15.836268.9387.65.513024.8115.6**Japan**Iwata \[[@bib35]\]Type 1--22.854671.7623.35.513017.1106.5Iwata and Murai \[[@bib36]\]P25S9--20.348170.9498.75.513019.2106.8P23M7--20.849271.1534.05.513018.8104.3P24L4--21.651371.3591.15.513018.1105.3P23L5--21.651371.3578.05.513018.1107.4P45M9--20.849271.1534.05.513018.8104.3Iwata et al. \[[@bib37]\]Type W--21.751571.4693.85.513018.0115.2Midorikawa et al. \[[@bib38]\]L650S--21.450771.3602.25.513018.3100.2L850S--21.450771.3601.85.513018.3106.8Takeuchi et al. \[[@bib39],[@bib40]\]CY110M15--23.957472.0721.85.513016.3112.2CY138M15--23.957472.0721.85.513016.3112.2**Canada**Tremblay et al. \[[@bib41]\]C1-1--16.237469.1461.35.513024.1120.5C2-1--16.237469.1443.55.513024.1119.4Dehghani and Tremblay \[[@bib21]\]S9--16.437769.2445.35.513023.8162.7S10--16.437769.2445.35.513023.8162.7S11--16.437769.2435.15.513023.8158.5S12--16.437769.2445.35.513023.8162.7Table 6BRB Simulation results: maximum and cumulative demands imposed by GLP-1 and GLP-2 loading protocols. Listed by specimen.Table 6SourceSpecimenGlobal loading protocol, GLP-1, YLR = 0.50Global loading protocol, GLP-2, YLR = 0.60*μ*~max~*CPDCPS* (%)*Ē*~*h*~*μ*~max~*CPDCPS* (%)*Ē*~*h*~**United States**Merritt et al. \[[@bib24]\]1D29.971695.71001.124.758478.1762.73D26.462794.9781.221.851077.3605.35D29.971695.71001.124.758478.1762.7Black et al. \[[@bib25],[@bib26]\]99--319.144292.4468.615.835774.8364.500--1228.066895.3889.823.154577.7683.9**Europe**Dunai et al. \[[@bib27]\]EWC800A28.467795.4926.823.455277.8706.4EWC800B28.467795.4910.323.455277.8693.5Ozcelik et al. \[[@bib28]\]BRB227.365095.2763.322.552977.6595.6BRB427.365095.2763.322.552977.6595.6**China (including Taiwan)**Li et al. \[[@bib29]\]; Sun et al. \[[@bib30]\]TJI-236.488196.81427.930.172179.21093.0TJII-132.477896.21158.326.763678.6899.5Liu et al. \[[@bib31]\]128.868795.51167.023.756077.9890.4Huang et al. \[[@bib32]\]BRB-W-V127.665695.2750.922.753577.6584.7Chou and Chen \[[@bib33]\]122.151893.6592.218.342176.0457.4Tsai et al. \[[@bib34]\]CR21.149193.2552.917.439875.6427.0WES-R24.056494.3623.419.845976.7485.2WES-C20.648093.1511.417.038975.5397.7WES-J21.048993.2551.217.339775.6430.3**Japan**Iwata \[[@bib35]\]Type 130.573095.8897.525.159678.2691.8Iwata and Murai \[[@bib36]\]P25S927.164595.1710.122.452577.5552.2P23M727.765995.2770.122.853777.6593.0P24L428.868795.5859.723.756077.9657.4P23L528.868795.5831.723.756077.9541.5P45M927.765995.2770.122.853777.6593.0Iwata et al. \[[@bib37]\]Type W28.969095.51019.423.856277.9773.3Midorikawa et al. \[[@bib38]\]L650S28.567995.4864.923.555477.8667.8L850S28.567995.4863.223.555477.8667.4Takeuchi et al. \[[@bib39],[@bib40]\]CY110M1531.976696.11045.726.362678.5801.8CY138M1531.976696.11045.726.362678.5801.8**Canada**Tremblay et al. \[[@bib41]\]C1-121.650593.5671.417.841075.9514.4C2-121.650593.5640.717.841075.9493.7Dehghani and Tremblay \[[@bib21]\]S921.851093.5635.318.041475.9495.5S1021.851093.5635.318.041475.9495.5S1121.851093.5621.718.041475.9484.1S1221.851093.5635.318.041475.9495.5

2. Experimental design, materials, and methods {#sec2}
==============================================

The following subsections provide a complete description of the methods used for acquisition of the data shared in this article.

2.1. Database of past experimental tests of full-scale and large-scale BRBFs {#sec2.1}
----------------------------------------------------------------------------

As pointed out in Aguaguiña et al. \[[@bib1]\], the values for the parameter *YLR* typically range from 0.50 to 0.70 in actual buckling-restrained braced frames (BRBFs), depending on the type of end-connections used (i.e., bolted, pinned, welded) and bracing configuration employed (diagonal or chevron). Since the range over which *YLR* is evaluated directly influences the relative deformation of the BRB, according to Equations (1)--(3) in Aguaguiña et al. \[[@bib1]\], it is important to define it in a more realistic way. To this end, the study relied on publicly available data from past experimental tests on BRBFs conducted at a full-scale and large-scale. A total of 12 relevant experimental campaigns, published between 2004 and 2018 \[[@bib2], [@bib3], [@bib4], [@bib5], [@bib6], [@bib7], [@bib8], [@bib9], [@bib10], [@bib11], [@bib12], [@bib13], [@bib14], [@bib15], [@bib16], [@bib17], [@bib18], [@bib19], [@bib20], [@bib21], [@bib22], [@bib23]\], were compiled to investigate the values that the *YLR* take in very detailed BRBF specimens. [Table 1](#tbl1){ref-type="table"} summarizes the information regarding the 12 experimental studies.

2.2. Database of past cyclic tests of individual BRBs {#sec2.2}
-----------------------------------------------------

In Aguaguiña et al. \[[@bib1]\], a total of 35 BRB specimens were selected from 16 experimental investigations and tests published between 2002 and 2018 \[[@bib21],[@bib24], [@bib25], [@bib26], [@bib27], [@bib28], [@bib29], [@bib30], [@bib31], [@bib32], [@bib33], [@bib34], [@bib35], [@bib36], [@bib37], [@bib38], [@bib39], [@bib40], [@bib41]\]. These tests were conducted in the United States (2), Hungary (1), Turkey (1), China (3), Taiwan (2), Japan (5), and Canada (2). The tests database includes typical BRBs (20), all-steel BRBs (7), and BRBs with steel mortar planks (8). Further, the dissipative core of the BRBs was made either of low-yield-point steel (4), mild steel (19) or high-strength steel (12) material. [Table 2](#tbl2){ref-type="table"} summarizes the information regarding the 16 experimental studies and the properties of the 35 selected specimens, and it constitutes the analysis matrix of the referred study \[[@bib1]\]. The information listed in [Table 2](#tbl2){ref-type="table"} includes: source of data; specimen denomination; loading protocol used for tests; BRB core material specification; steel core material properties (*F*~*ysc*~, *ε*~*y*~); steel core geometry (*A*~*sc*~, *L*~*y*~); and BRB yield force and yield deformation (*P*~*ysc*~, Δ~*by*~).

2.3. Numerical simulation of cyclic tests of BRBs under different loading protocols {#sec2.3}
-----------------------------------------------------------------------------------

The *Open System for Earthquake Engineering Simulation* (OpenSees) platform \[[@bib42]\] was employed for both modeling and numerical simulations of cyclic tests of BRBs. The model was built considering the typical setup for uniaxial cyclic tests of BRBs. It consisted of a two-node truss element with a length equal to that of the yielding segment of the BRB specimen, *L*~*y*~. That is, following the assumption that most of elastic and inelastic deformations take place within the yielding segment of the BRB, small elastic deformations in the transition and connection zones were totally neglected. The BRB model is illustrated in [Fig. 1](#fig1){ref-type="fig"}. For further details of the modeling and calibration procedure, the reader is referred to Aguaguiña et al. \[[@bib1]\].

As described in Aguaguiña et al. \[[@bib1]\], five different code-prescribed loading protocols were evaluated in this study: United States (US); Europe (EU); China (CN); Japan (JP); and Canada (CA). To quantify and compare the demands imposed to BRBs by the five different loading histories, it was convenient to specify the deformation amplitudes, Δ~*b*~, in terms of a common quantity. In this work, all the loading protocols were set in terms of the steel core strain, *ε*~*b,sc*~, which only depends on the geometric properties of the BRB specimen (i.e., *L*~*y*~). Thus, the US, EU, and CN loading sequences, whose deformation amplitudes were indexed as a function of the BRB design deformation, Δ~*bd*~, needed to be converted so that the deformation levels were also presented in terms of *ε*~*b,sc*~, as the JP and CA loading protocols. Here, two important assumptions were made for estimation of the maximum design demand of BRBs: (1) the design inter-story drift ratio equals the drift limitation in the US, EU, and CN codes; and (2) the design deformation demand, Δ~*bd*~, is evaluated considering two values of the parameter *YLR*: 0.50 and 0.60. [Table 3](#tbl3){ref-type="table"} presents the US, EU, CN, JP, and CA loading histories, in terms of *ε*~*b,sc*~, used for simulations. Additional details on the definition of the loading histories for analyses can be found in Aguaguiña et al. \[[@bib1]\].

In Aguaguiña et al. \[[@bib1]\], two new loading sequences, named as GLP-1 and GLP-2, were proposed as global loading protocols for qualification testing of BRBs. These loading histories were derived based on (1) the review of the background and definition of loading protocols for cyclic tests of BRB prescribed in different codes, and (2) the results from numerical simulation of cyclic tests of BRBs under five different loading regimes (i.e., US, EU, CN, JP, and CA). GLP-1 constitutes a loading protocol for an upper level of demand (*YLR* = 0.50) whereas the loading history GLP-2 represents a lower level of demand (*YLR* = 0.60). Both loading histories were configured so that a series of conditions and criteria were satisfied (refer to Aguaguiña et al. \[[@bib1]\]). GLP-1 and GLP-2 loading protocols are defined in [Table 4](#tbl4){ref-type="table"}.

Regarding to analyses results, the force and deformation responses resulting from the application of different loading sequences constituted the main output data from numerical simulations. From the force and deformation data corresponding to each BRB specimen and loading protocol, other performance parameters were computed, including the maximum ductility demand, *μ*~max~, cumulative inelastic deformation, in terms of cumulative plastic ductility, *CPD*, and cumulative plastic strain, *CPS*, and cumulative dissipated energy, *Ē*~*h*~. The formulae for computation of *μ*~max~, *CPD*, *CPS*, and *Ē*~*h*~ are given in Equations (4) through (7) in Aguaguiña et al. \[[@bib1]\]. The post-processing of analyses results was done by using the MATLAB software. Taking into account that the test database is composed of 35 BRBs specimens, and that this study considered five code-prescribed loading protocols (i.e., US, EU, CN, JP, and CA) with two analysis cases for US, EU, and CN, a total of 280 static cyclic loading analyses were performed in OpenSees. On the other hand, the number of static cyclic loading analyses under the two proposed global loading protocols (i.e., GLP-1 and GLP-2) accounted for 70. These results are presented in this article as two datasets. [Table 5](#tbl5){ref-type="table"} presents the results of numerical simulation of cyclic tests of BRBs with code-prescribed loading histories, whereas [Table 6](#tbl6){ref-type="table"} presents the results corresponding to the analyses with the proposed global loading protocols.

### 2.3.1. Results of simulation of cyclic tests of BRBs under code-prescribed loading histories {#sec2.3.1}

[Table 5](#tbl5){ref-type="table"} presents the results from numerical simulations of cyclic tests of BRBs under the US, EU, CN, JP, and CA loading histories. The maximum steel core ductility as well as the cumulative imposed demands are reported for each of the 35 BRB specimens considered in Aguaguiña et al. \[[@bib1]\].

### 2.3.2. Results of simulation of cyclic tests of BRBs under proposed global loading protocols {#sec2.3.2}

[Table 6](#tbl6){ref-type="table"} presents the results from numerical simulations of cyclic tests of BRBs under the two proposed global loading protocols, GLP-1 and GLP-2. The maximum steel core ductility as well as the cumulative imposed demands are reported for each of the 35 BRB specimens considered in Aguaguiña et al. \[[@bib1]\].

Conflict of Interest {#appsec1}
====================

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

The authors are grateful for the financial support (Grant No. 51678449) received from the National Natural Science Foundation of China (NSFC).

[^1]: Typ. = typical BRB, whose restraining system is composed by a steel tube filled with mortar/concrete surrounding the steel core; All-S = all-steel BRB or "dry" BRB, whose restraining mechanism is composed by steel plates or sections, adapted to the shape of the steel core, typically assembled by bolting; SMPs = BRBs, first proposed by Iwata and Murai \[[@bib36]\], whose restraining system is composed by a pair of prefabricated mortar-filled steel channels (referred to as steel mortar planks, SMPs) assembled by welding.

[^2]: AISC\* = customized AISC loading protocol; EN15129\* = customized EN15129 loading protocol.

[^3]: *ε*~*b,sc*~ = axial strain of steel core of BRB = Δ~*b*~/*L*~*y*~.

[^4]: *ε*~*y*~ = core strain, *ε*~*b,sc*~, at first yield of test specimen.

[^5]: *ε*~*b,sc*~ = axial strain of steel core of BRB = Δ~*b*~/*L*~*y*~.

[^6]: *ε*~*y*~ = core strain, *ε*~*b,sc*~, at first yield of test specimen.