The effect of antifreeze reagent on seasonal frozen soils

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

Comparison of the pile testing results on Expo-2017 (Kazakhstan)

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 testing 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 – SCLT), static loading test (by GOST – SLT) and bidirection static loading test (by ASTM – BDSLT or O-cell) methods are presented in this paper. Experienced bored piles with length of 31.5 m, diameter 1000 mm. Bi-directional static loading test and Static compression loading test carried out in accordance to ASTM D1143-07 and Static loading test carried out in accordance to GOST 5686-94, (1994). Hereafter the results of underground testing by the piles with the methods of vertical static testing BDSLT are presented, which had been made on Expo 2017 projects, buildings of Pavilion in Astana, Kazakhstan

Values of the deformation modulus of soil at different ways of determining this amount

In accordance with Russian, Kazakh and European building regulations, the deformation modulus of soil should be determined in the laboratory and also apply in situ soil tests on the stages of engineering geology prospecting. In this paper we present data on the determination and adjustment of the deformation characteristics at different stages of constructio

Comparison of the pile testing results on Expo-2017 (Kazakhstan)

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 testing 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 – SCLT), static loading test (by GOST – SLT) and bidirection static loading test (by ASTM – BDSLT or O-cell) methods are presented in this paper. Experienced bored piles with length of 31.5 m, diameter 1000 mm. Bi-directional static loading test and Static compression loading test carried out in accordance to ASTM D1143-07 and Static loading test carried out in accordance to GOST 5686-94, (1994). Hereafter the results of underground testing by the piles with the methods of vertical static testing BDSLT are presented, which had been made on Expo 2017 projects, buildings of Pavilion in Astana, Kazakhstan