# Investigation of the Behaviour of Steel-Concrete-Steel Sandwich Slabs with Bi-Directional Corrugated-Strip Connectors

^{1}

^{2}

^{3}

^{4}

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Experimental Program

#### 2.1. Sandwich Slab Specimens

#### 2.2. Concrete Core Components

^{3}, 809 MPa, 50 mm and 1 mm, respectively. In this study, the steel fibres added to the concrete composition at a volume percentage of 1%.

#### 2.3. Mechanical Properties of CSC Shear Connectors and Steel Faceplates

#### 2.4. SCS Slab Specimens Preparing

#### 2.5. Required Equipment for Quasi-Static Concentrated Loading Test on SCS Slabs

## 3. Results and Discussion

#### 3.1. Failure Modes and Load-Displacement Curves

#### 3.2. Comparison of the Experimental Results with Previous Researches

_{c}for different specimens was also compared, as presented in Table 8. Regarding these results, the modulus of elasticity increased by increasing the compressive strength of the concrete core. Therefore, the maximum load-bearing capacity improved with the increase of the modulus of elasticity (E

_{c}). The obtained outcomes are represented in Figure 15, Figure 16, Figure 17 and Figure 18. According to Figure 15, in the specimen with J-hook connectors and NWC core, bearing capacity is dropped suddenly after the maximum resistance point of about 600 kN. According to this rapid reduction, failure occurs as a punching shear state. Conversely, using CSC shear connectors leads to increase bearing capacity without any drop in resistant; however, specimens with J-hook connectors deformed more. As it is seen in Figure 16 and Figure 17 with LWC and SLWC core respectively, the reduction after the maximum bearing point of about 250 kN occurs for J-hook connectors due to punching shear failure; however, this sudden drop in resistance is not observed in any of the slabs with CSC connectors. Additionally, compared with those manufactured using stud bolt connectors, CSC connectors resulted in higher bearing capacity of SCS slabs (Figure 18).

#### 3.3. Comparison of the Experimental Strength with the Predicted Strength

## 4. Flexural Capacity Prediction of SCS Slabs

_{pl}is the plastic moment capacity per unit length along the yield-line, c is the side length of the loading area, L

_{s}is the dimension of the slab specimens, which here is 1200 mm; L is the span between the supports.

_{c}= t

_{t}= t in Figure 22. The steel plates in SCS sandwich can be treated as the reinforcement in reinforce concrete. The SCS sandwich slab will deflect extensively and wide cracks are developed in the final loading [8]. After yielding of tension steel plate, the cracking of the concrete will continue to rise towards the compression steel plate. In this case, the strain at the bottom plate is enormous compared to the top steel plate [24]. The moment capacity of the slab is reached when the neutral axis moves near to the lower surface of the compression plate (i.e., ${x}_{c}\approx 0$), and the bottom plate is fully yielded. Therefore, in the case of ${t}_{t}={t}_{c}=t$, the moment of resistance of the sandwich section becomes [24]:

_{s}is section area of connectors. Additionally, ${\sigma}_{ult}$ is specified tensile strength of CSC but $<$500 Mpa. According to Table 6, all of CSC connectors have the same geometric properties as follows:

## 5. Comparison of the Results

_{R}based on the Eurocode 4 (Equation (6)), the ultimate flexural strength has a good agreement with under 10% error for all specimens, except for the specimens SCSLWC and SCSB10-1 with 25% and 30% error, respectively. This is also repeated for the proposed relation by Yousefi and Ghalehnovi [32] (Equation (7)) with a good agreement for all CSC systems by below 10% error, exceptionally for SCSLWC specimen that has an unacceptable error of 30%.

_{R}) based on the push-out test [42,43,44,45,46,47].

## 6. Conclusions

- The typical behaviour of the SCS with NWC core in terms of both stiffness and resistance was better than those produced with plain LWC core and LWC core reinforced by steel fibres. However, the NWC core was about 35% heavier than the LWC and SLWC cores that can be a fundamental problem for specific applications such as ship hull;
- The experiments results illustrated that in areas where stress concentration was more significant, the failure of the shear connectors from the plug welds was inevitable;
- The use of LWC core decreased significantly the energy absorption at both yield and ultimate points compared with NWC core, while this characteristic was improved with steel fibres about 8% and 27%, respectively, compared with LWC with no steel fibres;
- The use of LWC core with and without fibres significantly increased ductility. This is in contrast to samples with J-hook connectors. However, it is too early to conclude with this limited number of samples and it can be a more detailed study on the subject of future studies;
- Using steel fibers reduced the punching shear in SCSSLWC by controlling cracks propagation;
- Except for the SCSLWC slab with LWC core, in the other specimens, the ultimate flexural capacity based on the experiments were in acceptable agreement with the results of the Eurocode 4 (Equation (6)) and the proposed relation by Yousefi and Ghalehnovi [32] (Equation (7)) by below 10% error. It is important to note that the Equation (7) was obtained with the NWC core, and future research is needed to predict the inter-layer shear strength (P
_{R}) for CSC system with LWC core and SLWC core under push-out tests.

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## Data Availability

## Notation

ALE | arbitrary-Lagrange-Eulerian |

CSC | corrugated-strip shear connectors |

c | side length of the loading area |

d | diameter of stud shear connectors |

${E}_{c}$ | elastic modulus of concrete |

${f}_{c}$ | cylinder strength of concrete |

${\mathsf{\u2206}}_{u}$ | displacement at ultimate strength |

${\mathsf{\u2206}}_{y}$ | displacement related to the yield point |

LWC | lightweight concrete |

L_{s} | dimension of the slab specimens |

L | span between the supports |

m_{pl} | plastic moment capacity per unit length |

NWC | normal weight concrete |

PNA | plastic neutral axis |

${P}_{R}$ | interlayer shear strength of CSC connectors |

SCS | steel-concrete-steel |

${\sigma}_{y}$ | yield strength of the steel plate |

## References

- Meghdadaian, M.; Ghalehnovi, M. Improving seismic performance of composite steel plate shear walls containing openings. J. Build. Eng.
**2019**, 21, 336–342. [Google Scholar] [CrossRef] - Karimipour, A.; Edalati, M. Shear and flexural performance of low, normal and high-strength concrete beams reinforced with longitudinal SMA, GFRP and steel rebars. Eng. Struct.
**2020**, 21, 111086. [Google Scholar] [CrossRef] - Soty, R.; Shima, H. Formulation for maximum shear force on L-shape shear connector subjected to strut compressive force at splitting crack occurrence in steel-concrete composite structures. Procedia Eng.
**2011**, 14, 2420–2428. [Google Scholar] [CrossRef] [Green Version] - Wright, H.; Oduyemi, T.; Evans, H. The experimental behaviour of double skin composite elements. J. Constr. Steel Res.
**1991**, 19, 97–110. [Google Scholar] [CrossRef] - Roberts, T.; Edwards, D.; Narayanan, R. Testing and analysis of steel-concrete-steel sandwich beams. J. Constr. Steel Res.
**1996**, 38, 257–279. [Google Scholar] [CrossRef] - Karimipour, A.; Edalati, M. Retrofitting of the corroded reinforced concrete columns with CFRP and GFRP fabrics under different corrosion levels. Eng. Struct.
**2020**, 227, 145872. [Google Scholar] - Dai, X.X.; Liew, J.R. Fatigue performance of lightweight steel-concrete-steel sandwich systems. J. Constr. Steel Res.
**2010**, 66, 256–276. [Google Scholar] [CrossRef] - Bowerman, H.; Coyle, N.; Chapman, J. An innovative steel/concrete construction system. Struct. Eng.
**2002**, 80, 33–38. [Google Scholar] - Subedi, N.K.; Coyle, N.R. Improving the strength of fully composite steel-concrete-steel beam elements by increased surface roughness—An experimental study. Eng. Struct.
**2002**, 24, 1349–1355. [Google Scholar] [CrossRef] - Zhao, X.L.; Han, L.H. Double skin composite construction. Prog. Struct. Eng. Mater.
**2006**, 8, 93–102. [Google Scholar] [CrossRef] - Xie, M.; Foundoukos, N.; Chapman, J. Static tests on steel-concrete-steel sandwich beams. J. Constr. Steel Res.
**2007**, 63, 735–750. [Google Scholar] [CrossRef] - Bowerman, H.; Chapman, J.C. Bi-steel steel-concrete-steel sandwich construction. Compos. Constr. Steel Concr.
**2000**, 12, 656–667. [Google Scholar] - Mohamedien, A.; Omer, A. Finite Elements Modeling and Analysis of Double Skin Composite Plates. IOSR J. Mech. Civ. Eng.
**2014**, 6, 254–261. [Google Scholar] [CrossRef] - Karimipour, A.; Ghalehnovi, M.; de Brito, J.; Attari, M. The effect of polypropylene fibres on the compressive strength, impact and heat resistance of self-compacting concrete. Structures
**2020**, 25, 72–87. [Google Scholar] [CrossRef] - Ghalehnovi, M.; Karimipour, A.; de Brito, J. Influence of steel fibres on the flexural performance of reinforced concrete beams with lap-spliced bars. Constr. Build. Mater.
**2019**, 229, 145264. [Google Scholar] [CrossRef] - Shariati, M.; Sulong, N.R.; Suhatril, M.; Shariati, A.; Khanouki, M.A.; Sinaei, H. Behaviour of C-shaped angle shear connectors under monotonic and fully reversed cyclic loading: An experimental study. Mater. Des.
**2012**, 41, 67–73. [Google Scholar] [CrossRef] - Karimipour, A.; Ghalehnovi, M. Comparison of the effect of the steel and polypropylene fbres on the flexural behaviour of recycled aggregate concrete beams. Structures
**2021**, 29, 129–146. [Google Scholar] [CrossRef] - Anvari, A.; Ghalehnovi, M.; de Brito, J.; Karimipour, A. Improved bending behaviour of steel fibres recycled aggregate concrete beams with a concrete jacket. Mag. Concr. Res.
**2019**, 12, 63–75. [Google Scholar] [CrossRef] - Yan, J.B.; Liew, J.R.; Zhang, M.H.; Wang, J. Ultimate strength behavior of steel-concrete-steel sandwich beams with ultra-lightweight cement composite, Part 1: Experimental and analytical Study. Steel Compos. Struct.
**2014**, 17, 907–927. [Google Scholar] [CrossRef] - Liew, J.R.; Sohel, K.; Koh, C. Impact tests on steel-concrete-steel sandwich beams with lightweight concrete core. Eng. Struct.
**2009**, 31, 2045–2059. [Google Scholar] [CrossRef] - Liew, J.R.; Sohel, K. Lightweight steel-concrete-steel sandwich system with J-hook connectors. Eng. Struct.
**2009**, 31, 1166–1178. [Google Scholar] [CrossRef] - Yan, J.B.; Liew, J.; Zhang, M.H. Ultimate strength behavior of steel-concrete-steel sandwich beams with ultra-lightweight cement composite, Part 2: Finite element analysis. Steel Compos. Struct.
**2015**, 18, 1001–1021. [Google Scholar] [CrossRef] - Leekitwattana, M.; Boyd, S.; Shenoi, R. Evaluation of the transverse shear stiffness of a steel bi-directional corrugated-strip-core sandwich beam. J. Constr. Steel Res.
**2011**, 67, 248–254. [Google Scholar] [CrossRef] - Sohel, K.; Liew, J.R. Steel-Concrete-Steel sandwich slabs with lightweight core—Static performance. Eng. Struct.
**2011**, 33, 981–992. [Google Scholar] [CrossRef] - Sohel, K.; Liew, J.R. Behavior of steel-concrete-steel sandwich slabs subject to impact load. J. Constr. Steel Res.
**2014**, 100, 163–175. [Google Scholar] [CrossRef] - Leng, Y.B.; Song, X.B. Flexural and shear performance of steel-concrete-steel sandwich slabs under concentrate loads. J. Constr. Steel Res.
**2017**, 134, 38–52. [Google Scholar] [CrossRef] - Zhao, C.; Lu, X.; Wang, Q.; Gautam, A.; Wang, J.; Mo, Y. Experimental and numerical investigation of steel-concrete (SC) slabs under contact blast loading. Eng. Struct.
**2019**, 196, 109337. [Google Scholar] [CrossRef] - Yan, C.; Wang, Y.; Zhai, X. Low velocity impact performance of curved steel-concrete-steel sandwich shells with bolt connectors. Thin-Walled Struct.
**2020**, 150, 106672. [Google Scholar] [CrossRef] - Golmohammadi, M.; Ghalehnovi, M.; Yousefi, M. Experimental investigation of steel-concrete-steel slabs with stud bolt connectors subjected to punching loading. AUT J. Civ. Eng.
**2019**, 3, 93–106. [Google Scholar] - Yousefi, M.; Ghalehnovi, M. Push-out test on the one end welded corrugated-strip connectors in steel-concrete-steel sandwich structure. Steel Compos. Struct.
**2017**, 24, 125–134. [Google Scholar] [CrossRef] - Yousefi, M.; Ghalehnovi, M. Finite element model for interlayer behavior of double skin steel-concrete-steel sandwich structure with corrugated-strip shear connectors. Steel Compos. Struct.
**2018**, 27, 149–158. [Google Scholar] - Yousefi, M.; Ghalehnovi, M. The Effect of Shear Connectors on the Bending Behavior of Steel-Concrete-Steel Sandwich Beams. Ph.D. Thesis, Ferdowsi University of Mashhad, Mashhad, Iran, 2017. [Google Scholar]
- BS EN 12390-1: Testing Hardened Concrete—Part 1: Shape, Dimensions and Other Requirements for Specimens and Moulds; British Standard Institution: London, UK, 2000.
- BS EN 12390-2: Testing Hardened Concrete. Making and Curing Specimens for Strength Tests; British Standards Institute: London, UK, 2009.
- BS EN 12390-3: Testing Hardened Concrete; Part 3: Compressive Strength of Test Specimens; British Standards Institution: London, UK, 2002.
- ASTM International Committee C09 on Concrete and Concrete Aggregates. Standard Test Method for Flexual Strength of Concrete (Using Simple Beam with Center-Point Loading) 1; ASTM International: West Conshohocken, PA, USA, 2016. [Google Scholar]
- ASTM C136 Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates; ASTM International: West Conshohocken, PA, USA, 2016.
- ASTM C29 Standard Test Method for Bulk Density (“Unit Weight”) and Voids in Aggregate; American Society for Testing and Materials: West Conshohocken, PA, USA, 2017.
- ASTM C127-01 Standard Test Method for Density, Relative Density (Specific Gravity), and Absorption of Coarse Aggregate; ASTM International: West Conshohocken, PA, USA, 2001.
- ASTM C128 Standard Test Method for Density, Relative Density (Specific Gravity), and Absorption of Fine Aggregate; American Society for Testing and Materials: West Conshohocken, PA, USA, 2012.
- ASTM E8/E8M-16a Standard Test Methods for Tension Testing of Metallic Materials; ASTM International: West Conshohocken, PA, USA, 2001.
- Ghalehnovi, M.; Karimipour, A.; de Brito, J.; Chaboki, H.R. Crack width and propagation in recycled coarse aggregate concrete beams reinforced with steel fibres. Appl. Sci.
**2020**, 10, 7587. [Google Scholar] [CrossRef] - Rankin, G.; Long, A. Predicting the ounching strength of conventional slab-column specimens. Proc. Inst. Civ. Eng.
**1987**, 82, 327–346. [Google Scholar] - Johnson, R.P.; Anderson, D. Designers’ Guide to EN 1994-1-1: Eurocode 4, Design of Composite Steel and Concrete Structures. General Rules and Rules for Buildings, Part 1; Thomas Telford Ltd.: London, UK, 2004. [Google Scholar]
- Karimipour, A. Effect of untreated coal waste as fine and coarse aggregates replacement on the properties of steel and polypropylene fibres reinforced concrete. Mech. Mater.
**2020**, 150, 103592. [Google Scholar] [CrossRef] - Karimipour, A.; Edalati, M. Influence of untreated coal and recycled aggregates on the mechanical properties of green concrete. J. Clean. Prod.
**2020**, 29, 124291. [Google Scholar] [CrossRef] - Karimipour, A.; Ghalehnovi, M.; de Brito, J. Mechanical and durability properties of steel fibre-reinforced rubberised concrete. Constr. Build. Mater.
**2020**, 257, 119463. [Google Scholar] [CrossRef]

**Figure 1.**Shear connectors in SCS sandwich structures. (

**a**) C-shaped connectors, (

**b**) L-shaped connectors, (

**c**) overlapped headed studs in DSC system, (

**d**) friction welding connectors in Bi-steel structure, (

**e**) J-hook connectors, (

**f**). corrugated-strip connectors (CSC).

**Figure 15.**The comparison of the load-displacement curve of SCS slabs with J-hook and CSC connectors with NWC core.

**Figure 16.**The comparison of the load-displacement curve of SCS slabs with J- hook and CSC connectors with LWC.

**Figure 17.**The comparison of the load-displacement curve of SCS slabs with J- hook and CSC connectors with SLWC core.

**Figure 18.**The comparison of the load-displacement curve of SCS slabs with stud bolt and CSC connectors with NWC core.

**Figure 20.**Energy absorption of specimens (

**a**) at the yield strength point and (

**b**) at the ultimate strength.

Specimens | Water (kg/m^{3}) | Cement (kg/m^{3}) | Steel Fibres (kg/m^{3}) | Light Weight Aggregate (kg/m^{3}) | Natural Coarse Aggregate (kg/m^{3}) | Natural Fine Aggregate (kg/m^{3}) | Water/Cement Ratio |
---|---|---|---|---|---|---|---|

NWC | 174 | 370 | - | - | 1172 | 690 | 0.47 |

LWC | 145 | 580 | - | 243 | - | 742 | 0.25 |

SLWC | 145 | 580 | 12 | 243 | - | 742 | 0.25 |

Specimens | Average Tensile Stress (MPa) | Tensile Strength Coefficient of Variation | Tensile Strength Distribution Factor | Average Compressive Strength (MPa) | Compressive Strength Coefficient of Variation | Compressive Strength Distribution Factor |
---|---|---|---|---|---|---|

SCSNWC | 3.75 | 0.041 | 0.011 | 38.50 | 0.57 | 0.015 |

SCSLWC | 3.40 | 0.082 | 0.034 | 28.43 | 0.61 | 0.021 |

SCSSLWC | 3.30 | 0.160 | 0.048 | 30.33 | 0.65 | 0.021 |

Aggregate Type | Apparent Density (g/cm^{3}) | Bulk Density (g/cm^{3}) | Water Absorption (wt%) | Crushing Index (%) | Porosity (%) |
---|---|---|---|---|---|

Normal weight | 2.76 | 2.65 | 1.441 | 31.0 | 3.88 |

Light weight | 1.40 | 1.15 | 1.124 | 18.3 | 1.57 |

Chemical Composition | Aggregate Type | |
---|---|---|

Natural | Lightweight | |

Ca(CO_{3}) (%) | 72.2 | - |

SiO_{2} (%) | 27.8 | - |

Ca Mg(CO_{3})_{2} (%) | - | - |

Ca Mg(CO_{3}) (%) | - | 100 |

Overall diffraction profile (%) | 100 | 100 |

Background radiation (%) | 22.53 | 25.12 |

Diffraction peaks (%) | 77.65 | 74.88 |

Peak area belonging to selected phases (%) | 16.09 | 47.15 |

Peak area of phase A (Calcium Carbonate Calcite) (%) | 11.14 | - |

Peak area of phase B (Silicon Oxide) (%) | 4.87 | - |

Peak area of phase A (Calcium Magnesium Carbonate) | - | 47.15 |

Thickness (mm) | Yield Stress (MPa) | Ultimate Stress (MPa) | Ultimate Strain | E_{s} (GPa) | |
---|---|---|---|---|---|

Steel face plates | 6 | 285 | 495 | 0.23 | 202 |

CSCs | 4 | 250 | 380 | 0.3 | 207 |

Sc (mm) | hc (mm) | $\mathit{\theta}\mathit{c}\text{}\left({}^{\xb0}\right)$ | fc (mm) | tc (mm) | bc (mm) |
---|---|---|---|---|---|

92.7 | 78.0 | 61.9 | 26.6 | 4.0 | 20.0 |

Plate | Number of Holes | The Diameter of the Holes (mm) | Number of Connectors | CSCs Spacing (mm) |
---|---|---|---|---|

top | 104 | 12 | 52 | 91 |

bottom | 88 | 12 | 44 | 91 |

Specimen | A_{s} (mm^{2}) | Equivalent Diameter d(eq) (mm) | n_{t} | h_{c} (mm) | t (mm) | γ_{c} (kN/m^{3}) | f_{c} (MPa) | E_{c} (MPa) | σ_{y} (MPa) for Plates | σ_{u} (MPa) for Plates |
---|---|---|---|---|---|---|---|---|---|---|

SCSNWC | 160 | 14.3 | 96 | 78 | 6 | 24.50 | 38.5 | 27,377 | 285 | 495 |

SCSLWC | 160 | 14.3 | 96 | 78 | 6 | 14.30 | 28.43 | 24,496 | 285 | 495 |

SCSSLWC | 160 | 14.3 | 96 | 78 | 6 | 14.50 | 30.33 | 25,074 | 285 | 495 |

J-hook NWC SCS6-100 [23] | 78 | 10 | 121 | 100 | 6 | 24.00 | 57.2 | 31,859 | 315 | 405 |

J-hook LWC SLCS6-80 [24] | 78 | 10 | 121 | 80 | 6 | 14.40 | 27.0 | 24,048 | 315 | 405 |

J-hook SLWC SLFCS6-80 [23] | 78 | 10 | 121 | 80 | 6 | 14.45 | 28.5 | 24,518 | 315 | 405 |

SCSB10-1 [29] | 78 | 10 | 121 | 80 | 6 | 24.00 | 38.5 | 27,377 | 323 | 560 |

Specimen | Energy Absorption at the Yield Strength Point (kN mm) | Energy Absorption at the Ultimate Strength (kN mm) |
---|---|---|

SCSNWC | 2299 | 23,666 |

SCSLWC | 795 | 18,918 |

SCSSLWC | 864 | 25,845 |

J-hook NWC [24] | 1262 | 27,986 |

J-hook LWC [24] | 256 | 17,149 |

J-hook SLWC [24] | 370 | 18,158 |

Stud bolt NWC [29] | 430 | 15,020 |

Specimen | i (%) |
---|---|

SCSNWC | 4.17 |

SCSLWC | 8.13 |

SCSSLWC | 9.78 |

J-hook NWC [24] | 13.6 |

J-hook LWC [24] | 9.20 |

J-hook SLWC [24] | 10.3 |

Stud bolt NWC [29] | 6.71 |

Specimen | P_{R} (kN)_{,} Equation (6) | P_{R} (kN), Equation (7) | m_{pl}, (kN m/m), Equation (6) | m_{pl} (kN m/m), Equation (7) | F_{p} (kN), Equation (6) | F_{p} (kN), Equation (7) | F_{p-exp} (kN) | F_{p-exp}/F_{p7} | F_{p-exp}/F_{p7} |
---|---|---|---|---|---|---|---|---|---|

SCSNWC | 58.5 | 60.9 | 69.5 | 72.3 | 646 | 672 | 670 | 1.04 | 1.00 |

SCSLWC | 53.2 | 49.5 | 63.2 | 58.8 | 587 | 546 | 410 | 0.70 | 0.75 |

SCSSLWC | 54.3 | 51.7 | 64.5 | 61.4 | 599 | 571 | 550 | 0.92 | 0.96 |

J-hook NWC SCS6-100 [23] | -- | 33.0 | -- | 62.4 | -- | 579 | 620 | -- | 1.07 |

J-hook LWC SLCS6-80 [24] | -- | 19.0 | -- | 29.1 | -- | 271 | 252 | -- | 0.93 |

J-hook SLWC SLFCS6-80 [23] | -- | 22.3 | -- | 34.2 | -- | 318 | 302 | -- | 0.95 |

SCSB10-1 [29] | -- | 29.8 | -- | 45.6 | -- | 424 | 550 | -- | 1.30 |

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Ghalehnovi, M.; Yousefi, M.; Karimipour, A.; de Brito, J.; Norooziyan, M.
Investigation of the Behaviour of Steel-Concrete-Steel Sandwich Slabs with Bi-Directional Corrugated-Strip Connectors. *Appl. Sci.* **2020**, *10*, 8647.
https://doi.org/10.3390/app10238647

**AMA Style**

Ghalehnovi M, Yousefi M, Karimipour A, de Brito J, Norooziyan M.
Investigation of the Behaviour of Steel-Concrete-Steel Sandwich Slabs with Bi-Directional Corrugated-Strip Connectors. *Applied Sciences*. 2020; 10(23):8647.
https://doi.org/10.3390/app10238647

**Chicago/Turabian Style**

Ghalehnovi, Mansour, Mehdi Yousefi, Arash Karimipour, Jorge de Brito, and Mahdi Norooziyan.
2020. "Investigation of the Behaviour of Steel-Concrete-Steel Sandwich Slabs with Bi-Directional Corrugated-Strip Connectors" *Applied Sciences* 10, no. 23: 8647.
https://doi.org/10.3390/app10238647