We will continue to adhere to science and technology leading and innovation driven, and effectively promote the “demonstration action of scientific and technological reform” and “six special actions” with practical measures.

High end support and low end support are fixed support hoisting precautions 1.

Cast in Sockets

There is no waste generated in the production plant and the installation site.

There are few supports in the structural construction stage and it is easy to pass.

The hoisting beam is used to set up long and short steel wire ropes to ensure that the stair hoisting is in normal use.

The use of standardized precast components has become a development trend in the field of civil engineering.

A stable and firm stair protection shall be customized with plywood.

At the same time, the reserved holes for rail installation are integrated to facilitate the installation of iron railings.

After construction, it can also play a leading role in promoting precast subway stations in Shenzhen.

If the time for workers to be familiar with the installation scheme is removed, the actual construction speed is to complete all the installation of one stair component every 30 minutes.

2、 The advantages of precast stairs in the construction industry of Shanghai Metro Station have become increasingly prominent.

The horizontal included angle a between the main sling and the lifting beam should not be less than 60 ° 3.

The installation of the first stair component The traditional construction method of shaft stair is to first erect the scaffold in the whole hall, then install the formwork, then pour the concrete, and finally remove the formwork and scaffold, which is time-consuming and laborious and has a large potential safety hazard.

Precast installation is adopted for subway entrance and air shaft stairs, which can greatly accelerate the construction progress, simplify the construction process and facilitate the construction management.

Precast staircases can reduce common quality problems of cast-in-place staircases and reduce construction difficulty.

The construction unit welcomes it.

The first cast stairs pilot project of Shenzhen Metro is located in five mu of land in Yantian District, Shenzhen.

After the stairs are installed in place, the installation gaps and connection holes can be filled with foam to prevent garbage from entering; After the stair is installed in place, the tread surface shall be protected in time to avoid damage to the tread edges and corners.

Recently, the first pilot project of precast stairs of Shenzhen Metro has been installed in No.

2.

Advantages of precast staircases 1.

During the installation and construction of precast stair sections and after assembly, finished products shall be protected.

3.

can be formed at one time to achieve the effect of clean water delivery.

The construction content is mainly to install stairs in the construction shaft.

In addition to the frequent use of precast stairs in residential buildings, they have also been found in the construction of urban subways..

At present, the standardized finalization has been completed, and the protective materials can be recycled and reused.

2.

Finished product protection 1.

The fair faced concrete surface is delivered directly, which has a good appearance.

The hoisting steel wire rope of the stair is vertical to the hoisting beam for easy positioning.

The finished product protection requirements are high.

The construction personnel should hold the stair board to adjust the direction, align the side line of the stair board with the installation control line on the stair beam, and stop and slowly put it down, and do not put it down quickly and violently.

The low span is adjusted by chain block to make the hoisting beam and the step horizontal.

On site installation guidance In this demonstration project, we adhere to the specific analysis of specific problems, give full play to our technical advantages, and achieve the whole process of consultation for the pilot project, from the design of stair components (including the completion of design changes through docking with the original design unit), to the control of stair component production and transportation, to the preparation of the construction scheme for cast stairs, and to the final on-site installation guidance.

The construction method of precast stairs in subway station is characterized in that it includes the following steps: step 1: lift the precast stairs from the ground into the subway station; Step 2: Place the precast stairs stably in the special installation box, and use the forklift to horizontally transport them to the installation site in the subway station; Step 3: Install slings on the precast stairs, use chain block to lift the precast stairs to the installation position in the subway station and accurately adjust them in place; Step 4: Assemble the precast stairs accurately in place and connect the embedded parts.

Shenzhen Branch is responsible for green building design, production management, construction guidance, and the whole process consultation, while assisting the on-site construction personnel in supervision and inspection.

1、 Shenzhen Metro has completed the first pilot project of precast stairs.

2 air shaft of Wusha section of Line 8, No.

2 air shaft of Shenwai High School Station.

The precast stairs can be used after installation, which reduces the on-site construction amount and improves the construction efficiency.

When the main sling is in place, the stair board should be installed vertically from the top to the bottom, and a slight pause should be made at about 30cm above the working floor.

2 air shaft of Shenwai High School Entrance/Exit C and No.

According to the statistics of installation duration on the project site, all 36 staircases were installed in only two days.

The surface of the precast stair is fair faced concrete, which is the finished surface.

After the installation, it is completed at one time, and there is no need to do the finishing.

By using the method of assembling stairs, it is only necessary to complete the component production in the prefabrication plant and transport it to the site for hoisting.

The hoisting speed of precast stairs is fast, and the labor demand is less than that of traditional processes.

3.

Anti slip strips, fixed points of embedded parts of railings, drip lines, etc.

4.

The Shenzhen Metro Assembled Stairs Pilot Project of Shenzhen High School Entrance/Exit C is characterized by complex terrain, large topographic relief, deep access to the ground, and great construction difficulty.

2.

When the precast stairs are stacked in the storage yard after production, the ground shall be hardened and padded with skids; During the installation and calibration of precast stairs, the damage to the edges shall be avoided.

The use of precast components in the secondary structure of a subway station can not only reduce the consumption of building materials, improve the quality of the structure and the degree of industrialization of the construction, but also shorten the construction period, reduce the construction cost, and especially significantly improve the internal construction environment of the subway station.

Effective measures such as wrapping, wrapping, covering and covering can be taken to protect finished products from impact damage and pollution.

After the basic position is in place, use a crowbar to fine tune the stair board until the position is correct, lay it flat, pay attention to the correct elevation, and then unhook it after correction.

Precast stairs have a good shaping effect.

After installation, conduct on-site review and summarize the successful completion of the first trial project of precast stairs in Shenzhen Metro, and the preliminary attempt and exploration in the construction of subway precast stations, which has accumulated valuable experience for the construction of related projects in the future.

The formwork erection, reinforcement and concrete construction of cast-in-place stairs are relatively troublesome.