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Pile foundations are commonly used in engineering practice to transfer the loads from heavy structures such as high-rise buildings to competent soil strata. In this manner, such complications as unfavorable geological conditions, compressible soil layers, and high levels of groundwater are avoided. Different types of piles are used in construction work. The specific type of pile used depends on the type of loading, the foundation soil, and the location of the groundwater table. The technical progress of large, bored piles and the continuous improvements of construction procedures and piling equipment today have created new possibilities. This paper describes a series of pile load tests that were performed in the capital city of Nur-Sultan, Kazakhstan. The control equipment, technological features are important for detailed information about the process of testing and the associated results make them more accurate and reliable. Keywords: pile, static test, load, equipment, soil

The article presents the results of numerical analysis for pile foundation in seasonally freezing soil ground. This project uses the static tests of soil by piles at the construction site of Cargo off-loading facilities (Prorva, Atyrau region, Kazakhstan). The project area is located along the east coast of the Caspian Sea, both onshore and offshore, near the Prorva oilfield, Kazakhstan. At present, the North Caspian Sea has a limited water depth (max 8 m). According to the test results have been made design changes in the pile foundation. Static tests (SCLT) were carried out on the piles with 16m in length and precast concrete joint pile foundations with a total length of 22m to 27m. This research is important for an understanding of the interaction mechanism of precast composite joint piles with seasonally freezing soil ground of the Caspian Sea coastal area of the site.

This paper presents estimations of bearing capacities of precast concrete joint piles at two construction sites in the regions of Port Prorva located in Western Kazakhstan. The capacities of the piles were predicted using the static pile load test data with the conventional interpretation methods. The results were compared to those from APILE analyses, analytical calculations based on the Kazakhstani standard method, and the pile driving analyzer. It was shown that the highest pile capacities were obtained from the Chin interpretation and Decourt extrapolation methods. The results from De Beer, Davisson, and Fuller and Hoy interpretation methods were found to be similar. The result from the Butler and Hoy interpretation method was similar to the ones obtained from pile driving analyzer and APILE analyses. The pile capacity obtained by the Kazakhstani standard method was found slightly higher, though it is applicable for estimating ultimate pile capacities. The yield capacity of the piles was determined under working loads. The methods used in the paper can also serve as practical guidelines to assess the capacities of driven piles installed in the field.

This article discusses the problem of the bearing capacity of piles with defects in the pile body. Field trials were performed using the non-destructive Sonic Logging (CSL) method. The object of the study is bored piles with a diameter of 1.0 - 1.5 m and a length of 8 - 55 m. This article solves the problem of bearing capacity of piles with defects of 10%, 20% and 30%, respectively, in the body of the pile. For modeling, we used load test data from bored piles at the LRT construction site. In this study, only the maximum strain value is needed to compile several cases with various defects using two-dimensional finite element analysis (FEMA) based on the Midas-GTS NX program. According to the results of field tests and modeling of piles, it was found that more than 20% of piles have defects. Field data and numerical simulations have also been confirmed on the recommendation of Bjerrum

Development of a geotechnical database for the young capital of Kazakhstan, Nur-Sultan city, became a paramount concern of both the scientific community and industry. The creation of the Kazakhstan model of the geotechnical database was based on a fixed dataset which included a city map with determined X, Y, and H coordinates and the user generated data obtained from the materials of engineering and geological surveys from more than 2000 boreholes. Based on the assessment of the built-up area of the city, six main engineering-geological elements (EGE) were identified. The territory of the city was regrouped into eight zones instead of the previous six based on the geological origin and stratigraphy interposition of the EGE. Engineering properties of the soils were considered for physical and mechanical characteristics, where the plasticity limits demonstrated an accurate correlation to the elasticity modulus E and distribution boundaries between the alluvial and eluvial types of the soil on the graph. So, the increased liquid and plastic limits are replicated by higher values of elasticity modulus E, and hence better strength characteristics of a particular soil layer and vice versa, while the moisture content and soil density did not show any obvious pattern and requires additional verification on the construction site. Finally, a geotechnical map was built for the driven piles and the optimal variations in the pile length for each zone were determined.

The late year’s globalization of the world economic and social fields implies a development of unified, acknowledged foundations for integration. In the economic field, such foundations are the norms and standards which allow participants of the production process in different countries to speak the same technical language and to apply identical requirements for the products and services produced in different countries. The reform concept of the system of technical regulation in the construction industry was approved by the Government of the Republic of Kazakhstan, as well as in many other countries. The testing of piles according to the ASTM (USA) standard and the GOST (Kazakhstan) standard was discussed. The methods of testing piles by these standards have some differences. The Kazakhstan standard has not changed since 2012. By contrast, the ASTM standard has been updated and accounts for the latest technological developments and methodics of tests including different equipment. The paper includes recommendations on the future modernization of Kazakhstan standards for pile testing and installation. The most relevant issue today is to update the national standards, harmonizing with international standards.

At the present time, Astana city is going on works by construction public transport system light railway transport (LRT). The article considers the project of LRT on problematical soils of Astana. The foundation of bridge created from bored piles with cross-section diameter of 1.0–1.5 m and length of 8–55 m. Design bearing capacity of each bored piles are from 4500 to 9500 kN. This paper presented results of integrity test (by ASTM D6760-08) and static load tests (by GOST 5686-94) of bored piles. In those conditions it is very important cases to control the integrity of concrete body of each bored piles. For checking the integrity which applying a Cross-Hole Sonic Logging method. Currently the non-destructive testing method are a cross-hole sonic logging offers the most reliable technique for assessment the integrity of bored deep pile foundation on construction site. Integrity inspections performed after installation are often the most reasonable alternative available to assess the shaft quality. The results used for interpretation the data of real site. Finally, some recommendations are presented for testing methods suitable for problematical ground conditions of Kazakhstan.

At the present time, in Astana city is going on works by construction public transport system LRT (Light Railway Transport). LRT is an overhead road with two railway lines. The first stage of construction is including construction of overhead road (bridge) with 22,4 km length and 18 stations. The foundation of bridge is the bored piles with cross-section 1.0HL5 m and length 8-КЗ 5 m. In these conditions, very important to control integrity of concrete body of each bored piles. For checking integrity- applying two methods - Low Strain Method and Cross-Hole Sonic Logging. The aim of this paper is to discuss the advantages and disadvantages of each method using the examples of a real application. The article presents loading tests of large diameter and deep boring piles on the construction site in new capital city of the Republic of Kazakhstan. Finally, some recommendations for testmg methods suitable for problematical ground conditions of Kazakhstan are introduced. Traditionally, pile load tests in Kazakhstan are carried out using static loading test methods. Static pile loading test is the most reliable method to obtain the load-settlement relation of piles. Results of static pile tests using the static compression loading test (by ASTM). static loading test (by GOST) and bi-direction static loading test (by ASTM) methods are presented in this paper. Experienced bored piles with length of 31.5 m. diameter 1000 mm. Hereafter the results of underground testmg by the piles with the methods of vertical static tests of SLT. BDSLT and SCLT are presented, which had been made on Expo 2017 projects, buildings of Pavilion m Astana. Kazakhstan.

Due to the fact that in the winter period, which in the Northern regions of the Republic of Kazakhstan lasts up to 6 months, and in the Southern regions – up to 4 months, construction companies are forced to suspend construction and installation works on the foundations. As a result, the total duration of construction of facilities increases, which leads to additional financial expenses. Therefore, new technological solutions are needed for the construction of foundations in winter, to ensure the continuity of construction and installation work. The purpose of the study is to develop a formula of chemical reagents for thawing and protection from the freezing of seasonally frozen soil in places where pile foundations are driven in winter conditions. For the study, a three-component mixture of chemical reagents of the following composition, wt.%, was selected: quick lime (CaO) – 75, calcium chloride (CaCl) – 20, sodium chloride (NaCl) – 5. The choice of the specified composition is determined by taking into account their specific chemical properties and special reactions when interacting with water and frozen soil. The active components of quick lime (CaO) are converted to Ca(OH)2 when interacting with a wet environment or water. This process is accompanied by spontaneous heat release. In the course of the study, a new composition of a chemical reagent based on quick lime was developed for local thawing and protection from the freezing of seasonally frozen clay soil in the areas of driving pile foundations. This composition has advantages in terms of reducing energy costs for thawing seasonally frozen soil, since when interacting with water, the proposed chemical reagent spontaneously releases heat (t = 100oC) and does not cool down for a long time despite the negative ambient temperature of the air.

The design, construction, and maintenance of pile foundations are dependent on special weather conditions in Northern and Central part of Kazakhstan. The winter months in these areas are very long which starts from November to March and the air temperature usually reaches – 40-50°C. These circumstances lead to the seasonal freezing ground, special physical behavior of soil, physical properties of construction materials. The main problem of pile driving in winter is frozen ground which is difficult to excavate and driving. Moreover, the Static Load Tests for estimating the bearing capacity of pile foundations do not show accurate records in frozen soil. To solve the problems mentioned above, a special antifreeze composition has been developed and established its protective effect against soil freezing in winter. The implementation of the proposed method leads to a high productivity of driving reinforced concrete piles without the risk of their destruction. This eliminates the need for additional drilling works and more powerful and expensive rock drills, if the soil is protected from freezing. According to a special formula, the optimal mass of antifreeze is calculated, which allows protecting the soil without harming not only the soil, but also the structure of the concrete pile and the environment. During the static load test, piles driven into soil that had been covered with antifreeze has showed more accurate bearing capacity data. Scientific and experimental studies have established that antifreeze reduces the compressibility of frozen soil.

The article considers the project a new railway station on problematical soils of Astana, as well as light rail LRT Project. This article includes a summary of dynamic and static tests of driven and bored piles. Also, it is given the methodology for determining the bearing capacity of piles. As an example of these methods, the results of the dynamic, static and new PDA (Pile Dynamic Analyzer) test of teamwork and piles of soil carried out on the construction site “The new railway station in Astana” and Project light railway LRT (Light Railway Transport) planned to build in time for the World Expo in Astana EXPO-2017. This paper presented a short description of changes to the concept of Kazakhstan pile foundation design and to use PDA and DLT and SLT pile load tests. By georadar survey was funded the areas which reported a hard rock at a depth of 16 meters and other soil layers.

This paper described using Low Strain Method and Cross-Hole Sonic logging (CSL) for identify of integrity of bridge foundations of LRT in Astana, Kazakhstan. The CSL is a method prescribed by ASTM D6760 - 08, Standard Test Method for Integrity Testing of Concrete Deep Foundations. This method is considered to be more accurate than sonic echo testing in the determination of soundness of concrete. The sonic access tubes do not contribute to the structural capacity of the pile. The bored piles of LRT are 1.0^1.5 m of diameters and 10^55 m of lengths. Design bearing capacity of piles is more than 4500 kN. At the testing period were founded defects in foundation bodies. To check of integrity were conducted by static load tests. The CSL test is based on the length of time for an ultrasonic wave to be propagated between any two of the selected tubes. The velocity of the propagated wave depends on the material through which the wave is transmitted. The aim of this paper is to discuss the advantages and disadvantages of Low Strain Method and CSL methods by analysis of field testing. For checking integrity applying two methods - Low Strain Method and Cross-Hole Sonic Logging. The aim of this paper is to discuss the advantages and disadvantages of each method using the examples of a real application.

At the present time, in Astana city is going on works by construction public transport system LRT (Light Railway Transport). LRT is an overhead road with two railway lines. The first stage of construction is including construction of overhead road (bridge) with 22.4 km length and 18 stations. The foundation of bridge is the bored piles with cross-section of 1.0-1.5 m and length of 8-35 m. A design bearing capacity of pile is 4500-8000 kN. Chinese drilling rigs Zoomlion was used for soil boring without casing. A polymer slurry is used to maintain the walls of boreholes in sand and gravel soils. In these conditions very important point is the integrity of concrete body of each bored piles. For checking the integrity was used two methods – the Low Strain Method and the Cross-Hole Sonic Logging. The aim of this paper is finding the advantages and disadvantages of each method which applying on testing site.

This article assesses the more productive methods for thawing seasonally frozen soils. The most rational and progressive method of thawing seasonally frozen soils involves putting antifreeze additives into the soil. New goals and objectives for the development of pile foundation construction technology in seasonally frozen soils in northern and central regions of Kazakhstan is presented.

Estimation of the geotechnical engineering and geological conditions of the ground is an essential aspect in design of pile foundations and the calculation of pile capacity and settlement. The results of some of static and dynamic pile integrity tests on problematical soils along the shores of the Ishim River in Astana and in the western part of Kazakhstan around the Caspian Sea will be presented. This data has been used to determine the length of H-piles for the new USA Embassy in Astana which is founded in soft soils. The paper will also present the geotechnical considerations for high rise buildings and buildings with unique architecture in difficult ground conditions in Astana (New Capital) and West Kazakhstan (the coast of Caspian Sea). The method of calculation of pile capacity and settlement based on static and dynamic pile integrity tests will be presented. It is found that geozoning is very important in design, construction and testing of piles in problematic ground in Kazakhstan especially in the new capital city of Astana. The paper presents the geotechnical challenges in the construction of piling foundations in problematical soils for Mega highway projects in Western Kazakhstan. Many factors, such as ground freezing, collapsing of soils, seismic zoning, are needed to be considered for design, testing and construction of the pile foundation.

The present work deals with the performance of screw piles constructed in gypseous soil of medium relative density; such piles are extensively used in piles foundations supported structures subjected to axial forces. The carrying capacity and settlement of a single screw pile model of several diameters (20, 30, and 40) mm inserted in gypseous soil is investigated in the present study. The gypsum content of soil used in tests was 40%. The bedding soil used in tests was prepared by raining technique with a relative density of 40%. A physical model was manufactured to demonstrate the tests in the laboratory. The model of screw pile has been manufactured of steel with a total length of 500 mm and helix diameters of 20, 30, and 40 mm continuous over the embedded depth of pile (400 mm). The results of tests showed decreasing the ratio of length to diameter (L/D) resulted in a higher axial carrying capacity of screw piles and low corresponding settlement.

The bearing capacity and settlement of pile foundation were greatly influenced by the temperature variations of soil ground around pile foundation. This paper presented a short report about laboratory static load tests by model precast concrete piles (cross-section 4 × 4 cm and length of 60 cm) in seasonally freezing soil ground. The depth of frozen soil was 10 cm, temperature -5℃, -10℃, +20℃. There were many factors influencing on pile foundations, such as ice in the ground, low temperatures and moisture of the soil. A series of tests of model piles in seasonally freezing soil ground were carried out, the results of bearing capacity of pile foundations and a settlement were compared. The results of the experiments were shown in charts. By application of numerical modeling the pile and soil base interaction vertical deformation in thermal changes of soil ground, the different settlement of piles. Modeling of thermal conditions of soils in software in accordance with real conditions on the construction site of Kazakhstan, analysis,and comparison of the obtained results ofthe settlement of pile foundations at low temperatures are presented in the paper.

Traditionally, pile load tests in Kazakhstan are carried out using static and dynamic load test methods. Static pile load test is the most reliable method to obtain the load-settlement relation of piles. Most of the static pile load tests are performed using reaction systems. Furthermore, cost and time for the static pile load test are relatively high compared to the dynamic pile load testing. Therefore, the number of pile load tests in construction site is limited to 2 or 5 piles in usual of constructed piles In Kazakhstan. This paper includes the short summary about dynamic and static tests by driven piles (cross-section 30×30 cm and length of 12 m). The methodologies of definition bearing capacity of the pile by aforementioned methods were also given. As an example for those methods, paper describes the results of the dynamic, traditional static and the new PDA (Pile Dynamic Analyzer) tests of cooperative work of soils and piles performed in the construction site of the New Railway Station in Astana. According to the results of tests were determined the possible depth of penetration and bearing capacity of piles, as well as recommendations on the device of working. The construction is part of the preparations for EXPO 2017. It will be 11 times bigger than the existing railway station. The height of the six-floor complex will be 49.5 metres, the width 116 metres and the length 630 metres.