## 6 Conclusions  
Through the full-scale test and numerical simulation of a steel assembled supporting structure, the impact of the temperature on the internal force on this type of supporting structure was explored, and the deformation process of the supporting structure under the temperature effect was evaluated. The following main conclusions can be drawn from the above results and discussion:  
1. Under the action of the thermal stress, the horizontal displacement of the retaining pile above the excavation face was more prominent. The deflection of waist beam 2 increased with the temperature rise, which made the deformation of retaining pile 3 consist of rigid rotation and flexural deformation, while retaining pile 2 only experienced flexural deformation. 2. In the heating stage, the crown of all the retaining pile moved out of the pit, and the horizontal displacement of the retaining pile crowns was in good agreement with the trend of change in the temperature. Moreover the horizontal displacement of the middle retaining pile crown increased more rapidly with the temperature rise. 3. Comparing our results with other works revealed that, at the same temperature difference, the horizontal displacement of steel support structures changes more significantly than that of concrete support structures. Figure 23: The displacement-temperature relationship of (**a**) the crown beam, (**b**) waist beam 1, and (**c**) waist beam 2. 4. After the excavation of the foundation pit was completed, the stress on the retaining pile near the excavation face was the largest; also, with the temperature rise, the stress on the retaining piles increased further. The increment in the stress on the bottom of the retaining piles was significantly greater than that in the stress on the crown of the retaining piles, which was extremely unfavorable to the stress on the piles. Therefore, the temperature effect should be considered as a working condition in design. 5. As the temperature rose, the crown beam deformed outside the foundation pit, while the waist beams deformed in the opposite direction. Compared with the crown beam and waist beam 2, the stress on waist beam 1 was more remarkably affected by the temperature; indeed, the stress on the end of waist beam 1 increased by 0.7 MPa/\({}^{\circ}\)C, so the stress on this position should be paid enough attention. 6. The rigid panels had a small stiffness, so they were severely affected by the temperature. For instance, when the temperature increased by 15 \({}^{\circ}\)C, the stress on rigid panels 1 and 2 enlarged by 78% and 82%, respectively. 7. The bending moment and shear strength of retaining pile 1 were markedly affected by the temperature, but piles 2 and 3 were basically stable. The deformation of the crown beam and the waist beams was coordinated with that of the retaining piles. After the temperature varied, the deflection of waist beam 2 changed the most, but the crown beam deflected the least. 8. The internal forces on the retaining piles, the crown beam, and the waist beams were all within the allowable strength range of the materials, and the deformation satisfied the specification requirements. The numerical calculation data were similar to the full-scale test results, and their deformation trend was basically identical; therefore, the developed simulation can be used to calculate the impact of the temperature on supporting structures in such engineering projects. Conceptualization, C.Z. ; Data curation, F.W., G.S. and B.L. ; Formal analysis, W.Z. ; Funding acquisition, H.F.; Investigation, C.Z. and H.F.; Methodology, F.W. and G.S. ; Software, W.Z. and B.L. ; Supervision, H.F.; Writing--original draft, F.W. ; Writing--review & editing, C.Z. All authors have read and agreed to the published version of the manuscript. This research was funded by the National Key Research and Development Program of China (No. 2016 YFC0802400); the National Natural Science Foundation of China (No. 51978630, 51909242, 52009125); the Scientific and Technological Research Program of Henan Province (No.