RU2548461C1 - Method to erect piled rafts - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: method to erect piled rafts includes arrangement of reinforced concrete piles in the form of pile clusters under pillars. Pile belts are arranged between clusters, then, as the solid reinforced concrete grill is arranged, all piles are combined in clusters and belts of piles into a single stiff spatial system forming openings between pile clusters.

EFFECT: increased efficiency of transfer load at foundation designs, reduced material intensity and labour intensiveness in arrangement of building foundations.

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Description

Technical field

The invention relates to the field of construction and can be used in the construction of foundations of multi-storey frame buildings, including in seismic areas.

State of the art

A known method of construction of a pile-slab foundation (patent RU 2379425 C1 IPC E02D 27/12, publ. 01/20/2010), in which the piles are immersed around the perimeter of the foundation, and the grillage slab is made of two parts - the outer one, having ledges up, immediately resting on piles, and internal - with ledges down, which relies on the external. At the same time, after reaching the calculated settlement, the external and internal parts of the grillage plate are rigidly combined, ensuring the joint operation of the pile-plate foundation.

The disadvantages of this method is the difficulty of predicting the loads that will be transmitted to the soil base of the inner part of the plate and piles of the outer part of the plate. The estimated draft determined by known methods is most often not achieved during the construction and operation of a building. In this case, it is necessary to design the inside of the slab based on its perception of the entire load from the building, which will lead to high material consumption of the structural solution of the inside of the slab. In addition, during the construction process, ensuring uniformity of sediment in the inner part of the slab is an elusive task. Accordingly, the provision of combining the outer part of the plate with the inner one, and their further joint work is doubtful.

A known method of construction of pile-slab foundations in seismic areas (patent RU 2300604 C1 IPC E02D 27/34, publ. 06/10/2007), in which piles of different lengths are immersed under the entire building. Long (main) piles are placed along the longitudinal and transverse axes of the bearing walls of the building, and short piles are placed in between the main. In this solution, a slab with short piles due to the limitation of lateral movements of the compressed soil of the base with long piles will transmit more than 15% of the load on the base.

The disadvantage of this method is the difficulty of predicting the bearing capacity of the slab with short piles, which should be clarified by the measurement results, precipitation during the construction process, and accordingly, the inability to make a final, rational constructive decision of the foundations at the design stage. In addition, despite the reduction in the length of piles in the intervals between the main piles, due to the need to use a plate of high rigidity (thickness), the method under consideration has high material consumption.

A known method of construction of piles, described in the pile-slab foundation (patent RU 2331738 C1 IPC E02D 27/12, publ. 08/20/2008), in which the piles are first immersed, combining them into bushes with grillages that absorb loads from the frame columns, providing for the release of reinforcement from the upper part of the grillages, prepare the base for the device of a thin plate, the releases of the reinforcement of which are connected with the releases of the reinforcement of the upper parts of the grillages. Concrete grillages are separated from slab concrete by seams, the width of which is assumed to be less than the calculated horizontal displacement of grill and slab elements under seismic effects.

The disadvantage of this method is the irrational use of the foundation plate only for the perception of seismic loads, loads from the weight of the building on the plate and its base are not transmitted.

In addition, the distributed loads from the stiffness diaphragms are transferred to the pile bushes, increasing the required number of piles in the bush.

SUMMARY OF THE INVENTION

The objective of the invention is to reduce the consumption of materials and labor when installing the foundations of a building, by increasing the efficiency of the transfer of loads (including seismic) to the construction of foundations and the base of frame buildings.

This object is achieved by the fact that in the method of erecting a pile-slab foundation, including the installation of reinforced concrete piles in the form of bushes of piles for columns, according to the proposed solution, piles are arranged between the bushes, then when the monolithic reinforced concrete grillage is arranged, all piles in the bushes and piles are combined a single rigid spatial system, forming openings between the pile bushes.

The arrangement of piles provides a more rational transfer of concentrated and distributed loads on the foundations and the base from the weight of the frame buildings with the simultaneous perception (if necessary) of seismic loads by the grillage structure, which reduces the complexity and material consumption of the solution for the construction of foundations of frame buildings (including for seismic areas) while maintaining the spatial rigidity of the structure and the advantages of the pile-slab foundation and ensuring the compatibility of deformations of the elements fun Ament under seismic loads.

The invention is illustrated by the drawing, which presents a three-dimensional visualization of the arranged pile-slab foundation.

The pile-slab foundation is made in the form of piles 1, forming bushes 2 under the columns, and tapes 3 piles 1 under the stiffness diaphragms of the frame building, combined by a monolithic reinforced concrete grill 4 into a single rigid spatial system with openings 5 between bushes 1 and piles 2.

The implementation of the invention

The sequence of the method of construction of the pile-slab foundation is as follows. The well-known calculation method (according to SNiP 2.02.03-85 *, SP 50-102-2003, SP 24.13330.2011 - updated edition of SNiP 2.02.03-85) determine the required number of piles in the bushes. The pitch of piles 1 for “hanging” driven piles in bushes 2 is taken to be 3d, where d is the diameter of the driven pile. The pitch of the piles in the tapes is taken constructively, for example 6d, or (if necessary) to transfer the load to the base from stiffness diaphragms, external enclosing structures by calculation using the known calculation method (according to SNiP 2.02.03-85 *, SP 50-102-2003, SP 24.13330.2011 - updated edition of SNiP 2.02.03-85). Piles 1 are arranged in bushes 2 and tapes 3. Then a monolithic reinforced concrete grillage 4 is assembled, combining all piles 1 in bushes 2 and tapes 3 into a single rigid spatial system, forming openings 5 between bushes 2 and ribbons 3 of piles 1.

Seismic isolation of above-ground structures is carried out by any known method, for example, by the device of seismic isolating supports.

Claims (1)

A method of constructing a pile-slab foundation, including the device of reinforced concrete piles in the form of bushes of piles for columns, characterized in that piles are arranged between the bushes, then, when the monolithic reinforced concrete grillage is arranged, all piles in the bushes and piles of tapes are combined into a single rigid spatial system, forming openings between the bushes of piles.

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