Metro Station

Column Renovation and Repair Construction Program

I. Project Overview

Shenzhen Huangmugang subway in the main structure has been completed and in the operation of the case, the owner requested to do the following changes.

1. Some walls and columns have color change, rot and damage, repair and renovation work on the existing walls to ensure the integrity of the walls.

2. The original roof columns have been renovated and cared for, but the underlying paint and putty layers have alkaline texture changes, resulting in the overall feeling of the wall being very dirty and old.

Ⅱ. Construction program

According to the design requirements, the scope of the subway for the columns, involving the construction of protection, wall damage repair in principle follow the protection → repair → remodeling of the construction sequence.

Protection: according to the content of the construction part, the scale of different, take the up and down the order of protection, and take the necessary measures to ensure that the construction process of the structural safety, to ensure that no secondary pollution. According to the construction requirements, in the protection construction of this project, the night construction is completed in a timely manner to clean up and restore the original, to ensure that the normal operation of the subway is not affected.

Repair:Remove the damaged layer to reinforce the structure, use the material 6400 model to cure the wall once; use SG-075 ceramic inorganic coating with fine sand to repair the holes and fill the concave surface. In order to reduce the trace marks, strain hysteresis, the repair parts and the surrounding structure need to take sanding treatment.

Remodeling: When the bottom surface foundation is well treated, use SG-075 ceramic inorganic coating spraying to reach the "wall structure engineering construction quality acceptance specification", and finally use ST-9 for spray coating treatment.

Ⅲ. Construction method

1、Construction protection work

(1) Worker training: necessary safety training for workers involved in the renovation work, including the use of safety equipment to avoid falling from heights and other aspects of knowledge training.

(2) safety equipment: ensure that workers are equipped with the necessary safety equipment, such as safety belts, helmets, protective glasses, etc., to protect their safety

(3) Site Safety Preparation:Ensure that there are enough safety warning signs around the site, set up necessary barriers and safety belts to ensure the safety of passage around the site.

2. Work Plan

(1) Before starting construction, a detailed work plan needs to be made, including the construction process, safety measures, material preparation, etc.

(2) Regular inspection and maintenance: Regular inspection and maintenance of equipment and tools required for renovation works to ensure their safety and reliability.

(3)Waste disposal: Properly dispose of the waste generated to avoid adverse effects on the environment and workers' health.

(4) Emergency plan: Formulate an emergency plan, including emergency rescue measures, emergency evacuation paths, etc., to cope with emergencies.

3、Construction method

(1) Construction to ensure that the temperature is between 5 ℃ ~ 35 ℃, relative humidity is not greater than 85 % of the environment under construction.

(2) the old wall reinforcement: the use of materials 6400 models to water 1:4 roll coating once, so that the wall to absorb the full material can be, such as drying can not be painted twice, in order to prevent the impact of the late wall pull cracking situation, there must not be traces of tears, the construction process in a timely manner with a dry roller to collect the dry, to be dry for 4 hours to carry out the next step in the construction;.

(3)Use SG-075 to convert water to 100%, i.e., material and water 1:1 mixing evenly for a spray, the purpose of the material and the grass-roots level have a good combination, and so on 2 hours after drying, and then use SG-075 to convert water to 30-50% of the second and third spraying repair work until the surface to achieve the "Technical Specification for Waterproofing of Walls" and "Acceptance of Construction Quality of Wall Structural Engineering Works", and to be dry in 4 hours. Carry out the next step of construction;

(4) Finally use ST-9 for coating protection treatment, construction method: single-component direct uniform spraying can be.

Ⅳ. Comparison before and after construction

Coating SG-075 is a comprehensive, multi-functional coatings: has good waterproof function, to do anti-adhesion, anti-dirt self-cleaning, fire retardant, acid and alkali resistance, salt spray resistance, anti-freeze, anti-ultraviolet and other functions, to protect the wall surface for 30 years does not blacken, do not get dirty, is in the industry's leading high-tech products, can cover the cracks in the cement level has or will produce.

Quality acceptance

Raw materials by the manufacturer's factory inspection certificate of conformity, engineering sample construction to meet the "renovation coating and acceptance regulations".

(1) Lightly hit with a small hammer, check the hollow drum, no hollow drum phenomenon;

(2) No cracks on the wall without alkali phenomenon;

(3) After coating, there is no obvious glare or discoloration.

The construction adopts "Compliance with FDA, REACH, ROHS food-grade acceptance standards" to ensure that before and after the construction, the product is harmless to human beings in the process of using the environment.