Construction method for narrow-base single-stand-column stepped foundation

Abstract

The invention discloses a construction method for a narrow-base single-stand-column stepped foundation. The construction method comprises the following specific steps of: performing foundation pit checking, performing pit bottom finishing, performing cushion-layer maintenance data lofting, binding, reinforcing a stand column reinforcement cage, positioning a bolt sample plate on the reinforcement cage, fixing a bolt group, performing anti-twisting rigid fixation on the reinforcement cage, mounting and fixing a step template, mounting and fixing a stand column template, performing acceptance inspection before foundation casting, grouting a foundation and correcting track, and inspecting basic data to perform backfill operation. The construction method effectively overcomes the problems that central pile data reference is absent after excavation, the stand column reinforcement cage of the foundation is relatively great in span and is unstable, and a foundation bolt group is difficult to mount and fix, effectively controls an outer deformation condition of the outer surface of a large concrete stand column, smoothly completes a construction task, reduces using quantity of steel beams and steel tubes, is good in data control after section base casting, achieves the very good effect in aspects of a construction process and quality control of the narrow-base single-stand-column stepped foundation, and has a project quality good rate of 98% or more.

Description

1. Technical field: [0001] The invention relates to a construction method of a step foundation with a narrow base and single column, and belongs to the technical field of step foundation construction of power transmission lines. 2. Background technology: [0002] At present, the step foundation design of domestic transmission lines is mostly based on the step type of four separate foundation pits. However, in some special areas, such as Hainan Province in my country, the operating lines often have to be considered to be attacked by strong typhoons, and the tower foundation is required to be relatively strong. Large self-weight and small footprint, so there is a narrow-base single-column stepped foundation. This type of foundation has a large amount of concrete and self-weight, which can ensure the stability of the power transmission tower in extreme weather, and has a small root opening and footprint. Its characteristic is that the foundation column is merged into one from t...

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is: in view of the large base plate area and large excavation area of ​​the narrow foundation single column foundation, the conventional foundation construction formwork support method has problems such as large steel beam span, poor stability, and vertical steel pipe support needs to be installed in the bottom layer, etc. Difficulties in construction, providing a narrow foundation single-column step foundation construction method, which effectively overcomes the problems of no central pile data reference after excavation, large and unstable span of the foundation column reinforcement cage, and difficult installation and fixation of the anchor bolt group; at the same time, it can effectively control The external deformation of the large concrete column was successfully completed, and the construction task was successfully completed. At the same time, the number of steel beams and steel pipes was reduced, and some materials were saved. After the foundation was poured, the data was well controlled, and the appearance of the foundation was good.