Papers by Keyword: Pile Foundation

Abstract: The article describes the methodology and results of geodetic observations of additional subsidence of two residential buildings with strip foundations on moist loess soil. Next to them, a pit was dug for the new building, which was deeper than the level of the soles of these foundations. The authors proved that of arranging the pit fence ensured the fulfillment of regulatory requirements for not exceeding the maximum allowable values of foundations of existing buildings by additional subsidence. The technology provided for the construction of a pit enclosure with sheet piling (I-beam No. 30) with a step of 1 m, with timber lagging between them. At the same time, the phasing of soil extraction in the initial stages under the protection of a soil berm was maintained. Then they installed the capping beam, struts, rakers and gradually raised the floor and outer wall of the parking lot of the new building. Sufficient convergence of the simulation results in the plane condition using the finite element method and field studies was determined. An elastic-plastic soil model of the "basement - foundations of an existing building - pit enclosure" system was used for modeling.

Abstract: Pile foundation equipped with a low-cost frictional type seismic isolation device is investigated. The frictional mechanism results from a contact between two surfaces of a half steel sphere mounted on the pile cap and the corresponding inner steel sphere embedded in the footing of upper structure. To verify the mechanical behaviors of the pile with frictional type seismic isolation device, tests, and its numerical simulations have been performed. The rotational friction device is found to be very effective in releasing the internal energy transferred from the pile foundation to the upper structure. The behavior of the friction-type device was studied by modeling using the nonlinear time history dynamic analysis. It was observed that the responses of the structures with devices can be approximated by using springs and dampers model.

Abstract: Pile foundation is the practical method to enhance earthquake-resistant ability for structures located in liquefiable soil sites. Soil liquefaction impact has been occurred such as Kashiwazaki-Kariwa NPP in 2007 Chūetsu offshore earthquake because of the soft backfill soil. To understand the behavior of pile foundations in liquefied soil during earthquake attack and conform to nuclear standard, seismic analysis with soil-structure interaction considering liquefaction using the finite difference program FLAC3D is developed to renew the traditional method used in nuclear industry. The models are verified according to a series of centrifuge model test results conducted in National Central University, Taiwan, to show the accuracy of seismic response prediction, and it provides the more advanced tool to demonstrate the detail of seismic response so that the utility and authority can easily decide the disaster prevention strategy.

Abstract: Based on the background of Dalian subway running through bridge pile foundation, a 3d numerical model is built by the finite element software MIDAS/GTS in order to research the laws of the internal force and the displacement of the pile and soil during the Construction process. The outcome reflects that the sedimentation value of the top of the pile is bigger than others. Because the bigger thrust about the shield machine, the horizontal displacement of the pile is increasing at first and decreasing at last from a positive into a negative. Because of the loss of the soil, the soil beside the pile collapses and causes strong friction force. The surface sedimentation value which is near the central line of the tunnel is bigger than other place. This paper is of good reference roles in the similar underground engineering in Dalian.

Abstract: The article discusses the causes of discrepancies in the values of the pile load capacity based on the results of calculations made on the basis of existing regulations and the pile load capacity after static load test on the construction site. A brief overview of the causes of discrepancies in analytical and practical values ​​of pile load capacity is provided in the article. The possible ways to solve this problem are suggested, namely, the development of the methods of analytical calculations of pile load capacity and the improvement of embedding technical processes. There is an example of such a discrepancy in the construction of a residential complex in Saint-Petersburg presented in the article. It was found that the variation in the results is not caused by the imperfections in the method of calculations, but by the infringements of construction technology. The article provides recommendations to minimize the discrepancies between the calculated and actual values of pile load capacity.

Abstract: Based on the problem of tunnel running through bridge pile foundation, a 3d numerical model is built by the finite element software MIDAS/GTS in order to research the internal force and the displacement of the pile and soil during the Construction process. The sedimentation value of the top of the pile is bigger than others. Because the bigger thrust about the Shield machine, the horizontal displacement of the pile is increasing at first and decreasing at last from a positive into a negative. Because of the loss of the soil, the soil beside the pile collapses and causes strong friction force. The surface sedimentation value which is near the central line of the tunnel is bigger than other place. This paper is of good reference roles in the similar underground engineering in Dalian.

Abstract: Opportunities of factories, transport companies and piling driving machines does not allow to produce longer piles when it is necessary. Currently this problem could be solved by joining parts of piles. A wide range of pile joints are known therefore it is a problem for building companies to choose which one is more relevant. In this connection there is a need to identify what joint is the most optimal. In this work main types of joints are compared in accordance with up-to-date requirements to building constructions and technologies. On the basis of these comparisons it is concluded that the most effective is pin joint type

Abstract: This paper explains load tests of models of bored concrete piles. In 2014 an experiment was carried out using testing equipment. The testing equipment was constructed at the Faculty of Civil Engineering, VSB – Technical University of Ostrava. The purpose of the experiment was to test the feasibility and load carrying capacity of bored concrete pile models. During the experiment two models of floating bored concrete piles were loaded. The heel of the first pilot was adjusted, in order to verify only surface friction. The second pile was used to verify side and base resistance. The results of these load tests will be further used for the preparation of calculations and experiments on mixed pile foundations.

Abstract: The liquefaction failure forms are reviewed, including foundation strength failure, sand boil, seismic settlement, large ground displacement and flow slide. Taking pile foundations and buried pipeline as examples, there suggested some measures to reduce hazards of liquefaction.

Abstract: It is very important for the deformation control of the bridge pile foundation in the design of bridge with high piers. Using the Three Dimensions Numerical Simulation, the stabilizing project about anchor reinforced pile foundation which is based on the geological characteristics of the 405 federal highways is simulated analyzed. According to the stimulant result, we can see that anchor reinforced pile foundation can control the dimensions effectively and reduce investment compared with the general pile foundation.