## 3 Results  
Particular emphasis in obtaining the results of the fiber optics was given to high-rise blocks, namely block R where, as expected, the highest strain values of the fiber optic cable were obtained. \(C_{T}\) was found as 1.113 MHz/\({}^{\circ}\)C, and \(C_{\epsilon}\) was equal to 0.054 MHz/\(\mu\epsilon\). At the time of the measurements, the temperature field distribution was relatively stable and varied within +4 to +8 \({}^{\circ}\)C over the entire area of the B4 level of block R (Figure 8). The location of areas with lower temperatures in the center of the building along the load-bearing walls of the core is explained by the greater thermal conductivity of reinforced concrete structures. Considering the depth of the raft at \(-\)19 m and the allocation of the block R in the middle of the complex of buildings, the ambient temperature did not affect to the results of the FO strain measurements during recording. Considering that the measurements were taken in February 2022, as well as the cold climate of Astana, the data obtained from the temperature field in Figure 8 correspond to the expected results.  
Figure 9 represents a strain fluctuation along the fiber optic cable from 115 m to 615 m in length in the Y direction layout under the R block, embedded in the B4 level raft. The vertical axis represents the strain in the cable in \(\mu\epsilon\): positive values in tension, negative values in compression. The horizontal axis determines the position along the length of the fiber optic. In this case, the location of the cable along the Y axis in the high-rise block basement raft starts from 115 m, and the length is 567 m.  
Figure 7: Installment of fiber optic sensors on the concrete surface.  
Figure 10 shows the results of the strain for the fiber optic cable for R block in the back direction, i.e., after bypassing the Z and Y blocks, embedded in the horizontal X direction in the section from 1334 m to 1934 m. Here, the significant compression strains recorded in the sections were from 1379 m to 1499 m and from 1715 to 1948, and significant tension strain was seen in the area on the south side of the block R building with less load applied.  
As can be seen in Figure 11, the fiber optic results show alternating strain signs along the length of the fiber optic cable embedded in the raft of the lowest level, B4, of block R. Compression deformations prevail in the central part of the building core, in the zone  
Figure 8: Temperature field distribution in block R.  
Figure 10: Strain in the X direction in the B4 raft of block R.  
Figure 9: Strain in the Y direction in the B4 raft of the 75-storey block R building.  
of increased load from the reinforced concrete load-bearing walls. Tensile deformations are most focused on the extreme axes, as well as near the joints of the columns. The interpretation of compression zones by values is shown in Figure 12 and tensile zones in Figure 13.  
Figure 11: Fiber optic strain along the cable layout in block R, level B4.  
Figure 12: Zones subjected to compression strains.  
Tension zones according to Figure 13 are evenly distributed over values from \(-20\) to \(-40\)\(\mu\varepsilon\), with a slight predominance on the right (east) side of the building. Individual spots of \(-40\) to \(-60\)\(\mu\varepsilon\) are occasionally located along the outer contour of the building. The center, north, and east parts of the building have more stable patterns of accumulation of tensile stresses.