## 4 Methods
### Experimental Methods
#### 4.1.2 Wind Load Testing  
Wind load tests were conducted to verify the overall structural performance and validate the numerical model of the full sandwich element, all while considering the embedded connectors and anchorage details. The wind load was applied incrementally in pressure and suction on full-scale sandwich elements using a pressure chamber. The test specimens were produced to have surface dimensions of \(3.0\times 2.8\) m\({}^{2}\). The facings were made up of TRRPC with a nominal thickness of 25 mm and the core consisted of a 150 mm FC insulation layer. Both facings contained two layers of carbon textile grid.  
Two element configurations underwent wind pressure tests, denoted as Single (S) and Double (D). In Figure 7, the first element comprised five rows of single connectors with a c/c distance of 0.5 m (dashed lines), while the second element had three rows of double connectors with a c/c distance of 1.0 m (dashed lines). The anchor details were designed similarly to that described for the anchor specimens above. However, in these specimens, the upper thickened sections were reinforced with one extra strip of carbon grid instead of a GFRP bar to simplify the production process of the elements.  
Figure 6: Schematic of the shear load capacity test set-ups; (**a**) positive shear load at upper anchors (\(H_{\text{up}}\)), (**b**) negative shear load at upper anchors (\(H_{\text{un}}\)), (**c**) positive shear load at lower anchors (\(H_{\text{lp}}\)) and (**d**) negative shear load at lower anchors (\(H_{\text{ln}}\)). Red filled circle indicates loaded bolt anchors.  
Testing was performed in a pressure chamber (capacity of \(\pm\) 3 kPa) configured as a four-sided room with an opening on one side. The sandwich element was mounted in a steel frame, affixed at the prescribed four anchorage points, then placed in the chamber opening, as depicted in Figure 8a. This established connection allowed for the element to move freely during loading. To prevent air leakage and pressure drop during testing, the gap surrounding the frame was sealed with elastic sealing tape.  
The simulated wind load was applied to the TRRPC facing at the inside of the climate chamber as incremental sequences (0.5, \(-\)0.5, 1.0, \(-\)1.0, 1.5, \(-\)1.5, 2.0, \(-\)2.0 kPa) consisting of positive wind suction followed by negative wind pressure and so forth. Load increments were manually set to the given load level and then held constant for approximately 60 s before applying the following load level. The load  
Figure 8: Photo of sandwich element mounted in the pressure test chamber (**a**) and location of displacement transducers on inner TRRPC facing (**b**).  
Figure 7: Illustration of wind load test on full sandwich elements: (**a**) single connector configuration (S) and (**b**) double connector configuration (D).  
was applied incrementally on each element as the capacities were initially unknown and it was of interest to apply both suction and pressure on the elements.  
The out of plane deformation of the inner TRRPC facing (facing out of the chamber) was measured in relation to the steel frame of the chamber at seven points using displacement transducers with a measuring range of \(\pm\) 25 mm. The locations of the seven measurement points are indicated in Figure 8b. Transducer positions 1, 2 and 3 measured displacements at mid-span, while positions 4, 5, 6 and 7 measured displacements near the top and bottom anchoring positions. During testing, the chamber pressure and displacements were measured at a sampling rate of 20 Hz.