## 1 Introduction  
The general design procedure for drilled shaft foundations in soils is primarily based on the ultimate values of drilled shaft skin friction and end bearing capacity [1]. The basic load transfer mechanisms were identified through early research on drilled shafts [2; 3]. This method is appropriate for soils in conventional geological settings in the absence of highly cemented calcite deposits. Calche is the hard lithification of fine-grained sediments, along with sand and gravel layers, which form through secondary cementation by calcium and magnesium carbonate [4; 5]. The federal highway code of design [6] considers calcite a sedimentary rock in the design procedure of deep foundations. Therefore, the design parameters of drilled shafts in interaction with rocks are recommended for the interaction of drilled shafts and calcite deposits. The shaft/caliche bond is considerably strong [7] and can bear high-range loading conditions. Calche layers are usually underlain by weak soils. The bending of the calcite deposits as part of the calcite-pile monolithic system is due to the additional flexural strength of these deposits in the soil profile [8]. The bidirectional Osterberg load test results in soils containing calcite indicate that the ultimate capacity of skin friction and shaft/caliche interaction is not achieved during the full-scale tests [9]. This issue can be anticipated due to limited slippage between the drilled shaft and the surrounding soil layers that prevent the drilled shaft from reaching its ultimate capacity [10]. Such a limitation affects the reliability of the measured results using Osterberg bidirectional tests, which are only reliable should the ultimate side resistance capacity of the pile be measured. The presence of competent calcite layers in soil is beneficial for reducing pile settlements. For example, vertically installed underpinned mini-piles (micropiles) were vertically installed and bonded to strong existing calcite layers to control the vertical displacement of the Mandalay Bay hotel/casino in Las Vegas, NV [11]. In this project, a jet-grouting method was used to enhance the bearing capacity [12] of the soil using micropiles to control the differential settlement of the building [13; 14]. [PERSON] et al. [15] conducted an analytical and experimental study on the capacity of the micropiles implemented in heterogeneous soil profiles containing rock layers. They asserted that the maximum load-carrying response of the micropile elements occurs when these types of piles are installed vertically in interaction with competent rock layers. Furthermore, increasing the stiffness of the piles using fiber reinforced polymers enhances the axial and bending capacity of piles in interacting with rock and highly cemented layers, and controls the displacement issues of the piles [16; 17; 18; 19; 20; 21; 22; 23; 24; 25; 26; 27; 28]. [PERSON] et al. [18] proposed that the satisfactory response of piles depends on the stiffness of the rock and calcite compared to the strength properties of these deposits. In the past, a few research studies have investigated the interpretation of the Osterberg test in the presence of strong, cemented calcite layers in soil. For instance, [PERSON] et al. [29] suggested that the current practice neglects the presence of highly cemented material in soil profiles close to the ground surface level. At a significant distance from the O-cell apparatus in the test procedure, the upward movement begins by mobilizing the soil layers with lower stiffness values, whereas a top-down test mobilizes the stiffer material in the early stages of loading. Therefore, the tests report two different load-movement responses near the pile head. [PERSON] et al. [30] recommended additional interpretation measures based on the different procedures of the bidirectional Osterberg test and conventional top-down test.