What are the factors that affect waterproof engineering?

At present, there are many varieties and specifications of waterproof materials in China, and the quality of products is uneven. At present, the domestic waterproof material market is chaotic, and many inferior waterproof materials flood the market.

Factors affecting the quality of waterproof engineering and countermeasures

The poor quality of building waterproof engineering is the direct cause of leakage in waterproof engineering. According to the investigation of authoritative organizations, there are 240 million m2 of linoleum and 270,000 tons of asphalt used to repair the waterproof layer of roofs in China every year, and the maintenance cost for building waterproof projects exceeds1200 million yuan every year. There are many reasons for leakage in waterproof engineering. Material quality, construction technology, design level, management and maintenance are important factors affecting the quality of building waterproof engineering. To improve the quality of waterproof engineering, we should take materials as the basis, design as the premise, construction as the key, strengthen management and maintenance, and comprehensively manage waterproof engineering.

The factors affecting the quality of waterproof engineering are analyzed as follows:

First, material factors.

The quality of waterproof materials is the foundation of waterproof engineering. At present, there are many varieties and specifications of waterproof materials in China, and the quality of products is uneven. At present, the domestic waterproof material market is chaotic, and many inferior waterproof materials flood the market. If unqualified waterproof materials are used in waterproof engineering, the quality of waterproof engineering will be seriously reduced.

By analyzing the quality of paper tire linoleum and waterproof coating, we can see that:

1. The quality of base paper of petroleum asphalt paper felt decreased. In 1950s, the base paper contained a lot of waste cloth pulp and a certain amount of coarse wool, but now most of them use waste paper and straw pulp, which reduced the tensile strength, elongation, moisture content and quality of linoleum.

2. The density of base paper increases and the oil absorption rate decreases. The oil soaking rate decreased from140% to160% to more than 1 15%. Because asphalt can't penetrate into the base paper, it is easy to cause asphalt felt to delaminate and rot.

3. The quality of petroleum asphalt is not good. After the 1960s, domestic petroleum asphalt with high wax content and sulfur content was used to produce linoleum, which led to poor aging performance, easy flowing and brittle cracking. Paraffin in asphalt had fluidity, which easily made the waterproof layer of linoleum lose its cohesive force gradually, leading to warping and falling off.

4. The quality of waterproof coating is low. In particular, some township enterprises producing waterproof coatings have weak technical force, backward production equipment, primitive operation technology, uncontrolled raw materials and poor quality of most products. According to the spot check of three manufacturers producing plastic ointment by relevant departments, only one manufacturer's plastic ointment is qualified, and the qualified rate is only 14.3%. If these unqualified waterproof materials are applied to waterproof projects, the quality of waterproof projects will be seriously reduced.

Second, the design factors

The waterproof design of building waterproof engineering is very important, which is the premise to ensure the engineering quality. However, there are the following problems in China's waterproof engineering design:

1. For a long time, there is no design specification for waterproof engineering in China, and designers have no specification to follow. There are no clear regulations on how to design waterproofing for different types and functions of buildings, what waterproof materials to use and what specific technical requirements are there.

2. Designers don't know much about modern waterproof knowledge, and they don't know much about the performance, scope of application and conditions of use of new building waterproof materials. They can't choose waterproof materials correctly according to the specific conditions of buildings, or they follow the old rules, or they leak or waste because of improper selection of materials.

Starting from 3. 1958, most roofing waterproof projects are simple waterproof methods of 350 # linoleum, second felt and third oil, which reduces the quality of roofing waterproof projects. From the previous investigation, it can be found that the phenomenon of roof leakage has increased obviously.

4. Most of the roof connection structures are out of date, and they still follow the practices of 1950s and 1960s. For example, when the linoleum is treated by laying wooden bricks and nailing wooden strips, it will often be warped, deformed and decayed due to wind, sun and rain, resulting in the destruction of cold water nodes and roof leakage.

5. In the design and construction of some buildings, the overall stiffness of the roof is not enough, and sometimes cracks appear due to large deformation; Some roof slopes are too small, the number of drainage pipes is insufficient or the diameter is too small, and the drainage route is too long, which makes the roof accumulate water and cause leakage.

Third, the construction factors

Through the investigation and analysis of housing leakage accidents, it is shown that construction factors are the main reasons for housing leakage. If there are qualified waterproof materials and excellent waterproof design, but the construction is not serious and the construction quality is poor, the house will still leak. Therefore, ensuring the construction quality is the key to improve the waterproof quality of buildings. The main factors causing poor construction quality are:

1. Lack of waterproof professional construction team, and even the use of workers who know nothing about waterproof technology for building waterproof construction, the consequences will inevitably lead to the failure of waterproof engineering.

2. Do not pay attention to the quality control and management of waterproof construction process, the leveling layer and waterproof layer are operated carelessly, the construction is not carried out according to the design drawings and construction technical specifications, and the acceptance is carried out in different processes and levels, especially the node parts are handled carelessly, leaving a hidden danger of leakage.

3. The quality of mastic boiled on the site of petroleum asphalt linoleum roof is unqualified; Did not do the mixture ratio test in advance or did not measure accurately according to the mixture ratio; If the boiling temperature is too high, the oil will volatilize too much, and the asphalt will age easily. High wax asphalt is used without dewaxing treatment.

4. Due to the construction period and schedule, the screed-coat was eager to lay the waterproof layer before it was dry, and effective measures such as exhaust roof were not taken, which led to bulging, delamination, decay and leakage of the waterproof layer.

5. Waterproofing failure is often caused by uneven coating thickness or thin coating. For another example, some construction units use some waterproof coatings with low solid content in order to get the project and reduce the cost as much as possible.

6. Rigid roof vibrating is not dense, the maintenance is not good, the thickness is insufficient, and the proportion of various sand and gravel materials in concrete is not handled properly; The isolation layer below the waterproof layer is not well done and has no isolation effect; Improper setting position of frame joints, serious imprecision of sealing material filling, etc. , will cause the rigid waterproof layer leakage.

Four, management and maintenance factors

After the project is completed and put into use, the management and maintenance of the housing project must be done well. If the management and maintenance are not good, not only the quality of materials, design and construction is high, but also poor management and maintenance will cause roof leakage. The causes of leakage due to poor management and maintenance are as follows:

1. The housing management department didn't assign a special person to inspect the roof project regularly, and some local defects were not handled in time, which led to the expansion of defects, crack development, joint damage and roof leakage over time.

2. The roof is not cleaned regularly, and the gutter, eaves gutter and drain are dredged. The downspout is blocked, and the roof accumulates water for a long time, which makes the waterproof layer delaminate and rot. Some roofs are not cleaned for a long time, plants breed, and the roots of plants plunge into the waterproof layer, destroying the waterproof layer.

3. In recent years, after many projects were put into use, TV antennas, light boxes, solar water heaters, advertising placards and other facilities were added to the roof, and the waterproof layer of the roof was constructed, so that the local damage of the waterproof layer was completed in time.

4. Some households keep poultry and play on the non-owner coiled waterproof roof or coated waterproof roof; Or pile up sundries and garbage on the roof to build a small house, which has been neglected for a long time, accelerating the decay and damage of the waterproof layer.

Five, improve the quality of waterproof engineering countermeasures

Because there are many factors affecting the quality of building waterproof engineering, the treatment measures should also be comprehensive.

(A) in terms of waterproof materials

In the chapter about the requirements of waterproof materials in the Technical Specification for Roofing Engineering, the technical performance requirements of various waterproof materials are put forward from the perspective of engineering needs, and it is stipulated that only when these requirements are met can they be used in roofing waterproof engineering. It is also stipulated that the waterproof materials used must pass the sampling inspection and certification of testing units designated by the construction departments of provinces, autonomous regions and municipalities directly under the Central Government before the products are allowed to enter the "market". At the same time, in order to control the quality of waterproof materials entering the "site", it is stipulated that the construction unit should sample and retest according to the new specifications. Only in this way can unqualified waterproof materials be effectively prevented from flowing into the "market" and "site". Once unqualified waterproof materials are found to enter the site, they are never allowed to be used in building waterproof projects.

(2) Waterproof design

In order to make designers follow in the design of roof waterproofing, the new code has two sections: "design points" and "detailed structure" for different roof projects. At the same time, it is also stipulated in the new regulations that designers should "design waterproof structures according to the engineering characteristics, regional natural conditions and the fortification requirements of roof waterproof grade, and detailed drawings should be provided for important parts". Roof drainage system and thermal insulation system should also be determined by calculation, instead of relying on experience or writing the words "two felts and three oils" as in the past.

(3) Construction quality

In each chapter of the new code, the technical requirements and quality standards of roof waterproof construction are stipulated. The construction unit is required to master the detailed structure and related technical requirements in the construction drawing through the blue prints.the design before the waterproof project construction, and prepare the construction scheme or technical measures of the waterproof project. Moreover, it also stipulates the qualifications of waterproof construction teams and operators, requiring that "roof waterproof projects must be constructed by professional waterproof teams or waterproof workers." It is strictly forbidden for non-waterproof professional teams or non-waterproof workers to carry out roof waterproof engineering construction. "It is emphasized that in the construction of waterproof engineering, inspection should be carried out according to the construction process and level, and the construction of the next process and level can only be carried out after passing the inspection. At the same time, the new code also stipulates the acceptance standard and inspection method of waterproof engineering quality to control the construction quality of roof waterproof engineering.

Only by doing a good job in design, materials, construction, management and maintenance can the service life of building waterproof engineering be guaranteed and extended.

Why do you need other supplementary information? I suggest you go to China Waterproof Enterprise Network for reference.