TSP Foundations

Contents

Introduction

1. Quantity takeoff and costing

labor costs for all types of work

2. Selection of efficient methods of work execution at

based on comparison of technological solutions

3. Selection of main machines and mechanisms

4. Calculation of process parameters of exposure

concrete in winter

5. Selection of suitable formwork type, calculation

individual structural elements of the formwork and

specification of all elements

6. Justification of technological decisions taken

for the entire set of designed works

7. Work Schedule

8. Quality control and acceptance of works

9. Occupational safety and environmental safety measures

List of literature

Substantiation of the accepted technological solutions for the entire set of designed works

The following works shall be performed prior to the foundation arrangement:

- access roads and roads are arranged;

- movement paths of mechanisms, storage places, reinforcement meshes and formwork are indicated, installation equipment and accessories are prepared;

- reinforcement nets, frames and formwork sets in the required quantity were brought in.

Formwork elements received on the construction site are placed in the area of the installation crane. All formwork elements shall be stored in a position corresponding to the transport, sorted by grade and type. It is necessary to store formwork elements under a canopy in conditions that prevent their damage. Shields are stacked no more than 1-1.2 m high on wooden gaskets; fights of 5-10 tiers with a total height of not more than 1 m with installation of wooden gaskets between them; other elements are put into boxes depending on dimensions and weight.

The formwork is installed and removed by means of a car crane.

- prior to installation of the formwork, the boards are pre-assembled in the panel in the following sequence:

- at the storage site the box is assembled from fights;

- shields are hung on fights;

Foundation formwork is arranged in the following order:

- the enlarged formwork panels of the lower stage of the shoe are installed and fixed;

- install the assembled box strictly along the axes and attach the formwork of the lower stage with metal pins to the base

After installation of the formwork of the lower stage, welded reinforcement grids of the foundation base are laid. Position of the second stage of the foundation is marked and the second stage box is installed. Then formwork of third stage and sub-column is installed in the same way. After that, formwork of cup-forming agent is installed .

The formwork is removed in the order opposite to installation. After the formwork is removed, the concreted foundations and formwork are visually inspected, formwork elements are cleaned from concrete, lubricated and prepared for installation by the next grip.

Installation of rebar grids is carried out from vehicles. Slinging is performed by 4-terminal crosspiece.

Reinforcement grids of shoe are installed on retainers providing protective layer according to design. After that reinforcement grids of sub-columns are installed with attachment of it to lower grid by means of binding wire. Installed nets and frames shall be reliably fixed and protected against deformation and displacements in the process of concrete mix laying.

The foundation concreting works include:

- reception and supply of concrete mixture;

- laying and compaction of concrete mixture;

- concrete care.

Concreting of foundations is carried out in two stages:

at the first stage, the foundation shoe and the sub-column are concreted to the bottom elevation of the insert;

at the second stage, the upper part of the sub-column is concreted after installation of the insert.

For loading with concrete mixture, rotary silos do not require reloading racks, but are supplied to the place of loading with concrete mixture by car crane, which sets the silos in horizontal position.

The concrete mixer reverses to the bunker and unloads. Then the car crane lifts the badge and in the vertical position supplies it to the unloading place. In the area of ​ ​ operation of an automobile crane, several hoppers are usually placed close to each other with the expectation that their total capacity is equal to the capacity of an auto-concrete mixer. In this case, all prepared bunkers-bunkers are simultaneously loaded with concrete mixture and then the crane alternately supplies them to the unloading place.

Each concrete layer is carefully compacted with depth vibrators. When compacting a concrete mixture, the end of the working part of the vibrator should be immersed in a previously laid layer of concrete for 5-10 cm. The step of rearranging the vibrator should not exceed 1.5 times its range. In the corners and at the walls of the formwork, the concrete mixture is additionally compacted with vibrators or with bayonets by hand drills. Do not touch the vibrator during operation to the fittings. Vibration at one position ends when subsidence stops and cement milk appears on the concrete surface. Remove the vibrator during rearrangement slowly, without turning off, so that the void under the tip is evenly filled with concrete mixture.

The interval between concreting stages (or laying concrete mix layers) shall be not less than 40 minutes, but not more than 2 hours.

Concreting of foundations is performed from curtain scaffolding.

After placing the concrete mixture in the formwork, it is necessary to create favorable temperature-moisture conditions for concrete hardening. Horizontal surfaces of concreted foundation are covered with covering material depending on climatic conditions.