Japan Yoshida Construction Industry Co., Ltd. was established in 1946 and is one of Japan's major professional waterproof construction companies. The company has 28 technical and managerial staff, 172 skilled professionals, a registered capital of 30 million yen, and an annual production value of 2 billion yen (about 150 million yuan). It is mainly engaged in construction of various waterproofing projects and construction of plugging and sealing projects. , waterproof technical advice and leakage water diagnosis.
Mr. Yoshida Yoshida, President of Yoshida Construction Co., Ltd., Mr. Takuya Tatsuo, Deputy Chief Architect, and Dr. Xu Yongdong, Deputy Minister of Technology Development, exchanged views with members of the Chinese Water Visiting Mission to Japan. Dr. Xu introduced Japan's waterproof technology in detail and answered questions raised by members of the China Waterproofing Mission.
Q: How did the Japanese Waterproof Project go from design to construction?
A: The Japanese engineering design is different from the Chinese engineering design. In China, both the architectural design and construction drawing design are commissioned by the owner to design the professional design institute. After the construction drawing is completed, the construction contract bidding will be carried out. The waterproof material selection and the waterproof construction design All of them are clearly completed before bidding. The advantage of this method is that the bidder and the tenderer have a clear target for the construction cost, which is convenient for the owner's investment control and construction cost control. However, with respect to the reasonableness of waterproofing technology, the influence of designers on the degree of mastery of waterproof materials and waterproofing techniques may have problems with the selection of materials and the irrational structure defense.
Japanese engineering bids and biddings implement international conventions. The scheme diagrams designed by the design office are used as the basic documents for bidding. In the scheme diagram, the designer put forward waterproof requirements for the parts that need waterproofing, but there is no specific structure and material selection. Bidders bid about 10% of the total cost. The construction drawings are designed by the general contractor after the bidder has won the bid according to the bidding plan of the owner, and the selection and structure of the specific materials are determined. In the construction drawing design, the special craftsmanship is conducted by the general contracting company for secondary bidding to complete the detailed project implementation and determine the technology, materials, and structures of the special process. The waterproofing project is determined through the second bidding process.
The selection of subway waterproof material is also conducted by the general contracting company. Each waterproof material factory or waterproof company selects the design and quotations for the waterproofing of the project according to the requirements of the bidder. The bidder (the contractor) shall receive the technical and reputation. After a comprehensive balance of costs, etc., determine the waterproof material and construction unit. After the waterproof construction unit is confirmed, the waterproof design shall be incorporated into the construction drawing according to the design scheme of the waterproof winning bid unit, to form a waterproof construction implementation document.
This waterproof design is fully targeted, design and construction of the unity. The water-proof design proposal put forward by the waterproof construction unit fully implements: 1. the rationality of the material selection; 2. the feasibility of the treatment of the waterproof structure node; 3. the definiteness of the requirements for other structural layers; 4. the construction progress and cost can be Controllability.
Q: How is the project waterproofing cost and settlement achieved?
A: At the time of general contract bidding, the cost of waterproof construction is estimated to be about 10% of the total construction cost. Waterproof construction costs include underground waterproofing of buildings, roof waterproofing, and bathroom waterproofing. When the general contractor bids for the waterproofing project at the design stage of the construction drawing, the general contractor shall submit the request technically. The bidder shall provide the scheme according to their respective technical characteristics, and the total contractor shall use the total construction cost at the time of bid as the control basis. Due to the owner's supervision and the general contractor's responsibility for the quality of the project, the waterproofing cost is usually controlled at about 10% at the time of bidding, and will not drop substantially.
After the waterproof construction unit signs the contract with the general contractor, it strictly follows the contract to construct and pay for the project. According to the agreement, the project payment can be paid monthly, or once in three months. By the date of payment of the project, the total package will automatically transfer the payment to the waterproof construction unit. There is no question of asking for money.
Q: What material is used for this subway project? How much is the cost?
A: The subway project is a double-hole box-type cast-in-place concrete structure, which is controlled by the construction cost. The polyester tire modified bituminous membrane is selected for the bottom plate and the top plate, and the hot-melt method is used for the construction; the side wall is selected from the self-adhesive butyl rubber waterproofing membrane. The construction joint is a butyl steel composite waterstop.
The construction price of self-adhesive butyl rubber waterproofing membranes is approximately RMB 700 yuan, of which 20 to 30% are materials and accessories, and the rest are labor costs, management fees, and taxes. A skilled operator can build about 40 per day. Skilled workers earn about $200 a day (approximately RMB 1,600). The company's net profit is about 5-6% of the cost.
Q: How is the waterproof project repaired?
Answer: The state does not provide warranty period for waterproofing projects. All types of work are strictly constructed in accordance with the design requirements, and there is usually no leakage. However, since the guarantee of waterproof quality involves many factors, it is difficult to determine the cause of water leakage. It is possible that the concrete itself is not dense, and it is also possible that construction operations such as tying steel bars may cause damage to the waterproof layer. Once there is leakage water, the total package cost will be The waterproof company repairs, so there is no warranty issue. In other words: Waterproof material is not used to make up for concrete defects. Leakage is not just the cause of waterproof construction.
There is also a general contractor (or owner) requesting contractual guarantee of waterproof quality. Under this circumstance, the waterproof company will increase the risk of gold by 20 to 30% during the quotation. The warranty period is 3 to 5 years. Once there is a problem of water leakage, It is repaired by the waterproof company for free.
Q: Does the country have qualification requirements for the waterproof company, or technical personnel and performance requirements?
Answer: No. A waterproof company is registered as an ordinary company and is licensed by the Ministry of Land, Infrastructure, Transport and Tourism. The reputation of a company is the vitality of a company. In order to accept more projects, a waterproof company must have a good social reputation. If there is a failure in the construction of a waterproof project, no one will believe you in the future and will not undertake it in society. engineering. Therefore, the performance of the company is very important. If the waterproof company has a lot of major projects, the social recognition is good. It is also necessary to pay attention to cooperating with a famous large-scale general contracting unit. It also shows that your construction quality and technical level are relatively high, and it can also be of great help in undertaking business.
In order to enable companies to undertake complex and important waterproofing projects, the company must be equipped with high-level registered architects and engineers and other technical personnel, and there is a special design department for waterproofing design. Operators are also relatively fixed. In Japan, few people often change jobs. The company believes that such people are not stable and their work is not pragmatic. If a person changes his work, no unit will be hired, and only temporary workers or unsteady working hours will be used. The wages of temporary workers are so low that they cannot maintain the normal life of the family. Employees working in enterprises can be paid once a year. The older the salary is, the higher the salary is. Each position has a corresponding position salary. The salary is very high, and it is also very honorable. Therefore, it is difficult to qualify in Japan. Only the work is absolute. Those with serious and profound technical skills can compete in certain positions. Japanese companies also rarely expel people. If an employee is not suitable for formal work in the company, let him be a cleaner or a handyman unless you resign.
Employees working under this system are all doing their utmost to perform their duties. Serious work, recognized by the company and society, seems to be the meaning of each individual's survival.
- Visit to Tokyo Metro Waterproof Project
On the morning of June 9, 2006, heavy rain in Tokyo, the delegation visited the construction site of the Tokyo Metro. The subway is the last section of the Tokyo Metro. The construction of the subway is basically completed. It has reached the stage of laying the track, and only the station part of the waterproof construction is still underway. A total length of 9 kilometers, divided into 7 stations, up to 40 meters deep from the ground.
Japan's Taicang Chemical Co., Ltd. undertook waterproofing work at one of the stations, 20 meters deep from the ground, and used a cracked self-healing polymer cement-based waterproof coating, which was divided into four types of construction depending on the parts and functions used. Construction method.
In this section of the Tokyo Metro water-repellent project, Japan's Taicang Chemical Co., Ltd. used a spray method. First, about 200g/m2 of polyester cloth was nailed to the maintenance wall, and the polyester cloth was bonded with adhesive. The paint was then sprayed on the polyester cloth twice to form a 1.5mm thick waterproof layer. Since the polyester fabric is fixed on the retaining wall in a spot shape, the polyester fabric and the surrounding wall are empty, and the side sprayed with the waterproof coating is directly connected with the 1.2 m-thick main structure reinforced concrete to achieve close contact with the structure. The effect and form a complete closed waterproof layer.
The construction method has been used in Japan for about ten years and has a good waterproof effect.
Mr. Yoshida Yoshida, President of Yoshida Construction Co., Ltd., Mr. Takuya Tatsuo, Deputy Chief Architect, and Dr. Xu Yongdong, Deputy Minister of Technology Development, exchanged views with members of the Chinese Water Visiting Mission to Japan. Dr. Xu introduced Japan's waterproof technology in detail and answered questions raised by members of the China Waterproofing Mission.
Q: How did the Japanese Waterproof Project go from design to construction?
A: The Japanese engineering design is different from the Chinese engineering design. In China, both the architectural design and construction drawing design are commissioned by the owner to design the professional design institute. After the construction drawing is completed, the construction contract bidding will be carried out. The waterproof material selection and the waterproof construction design All of them are clearly completed before bidding. The advantage of this method is that the bidder and the tenderer have a clear target for the construction cost, which is convenient for the owner's investment control and construction cost control. However, with respect to the reasonableness of waterproofing technology, the influence of designers on the degree of mastery of waterproof materials and waterproofing techniques may have problems with the selection of materials and the irrational structure defense.
Japanese engineering bids and biddings implement international conventions. The scheme diagrams designed by the design office are used as the basic documents for bidding. In the scheme diagram, the designer put forward waterproof requirements for the parts that need waterproofing, but there is no specific structure and material selection. Bidders bid about 10% of the total cost. The construction drawings are designed by the general contractor after the bidder has won the bid according to the bidding plan of the owner, and the selection and structure of the specific materials are determined. In the construction drawing design, the special craftsmanship is conducted by the general contracting company for secondary bidding to complete the detailed project implementation and determine the technology, materials, and structures of the special process. The waterproofing project is determined through the second bidding process.
The selection of subway waterproof material is also conducted by the general contracting company. Each waterproof material factory or waterproof company selects the design and quotations for the waterproofing of the project according to the requirements of the bidder. The bidder (the contractor) shall receive the technical and reputation. After a comprehensive balance of costs, etc., determine the waterproof material and construction unit. After the waterproof construction unit is confirmed, the waterproof design shall be incorporated into the construction drawing according to the design scheme of the waterproof winning bid unit, to form a waterproof construction implementation document.
This waterproof design is fully targeted, design and construction of the unity. The water-proof design proposal put forward by the waterproof construction unit fully implements: 1. the rationality of the material selection; 2. the feasibility of the treatment of the waterproof structure node; 3. the definiteness of the requirements for other structural layers; 4. the construction progress and cost can be Controllability.
Q: How is the project waterproofing cost and settlement achieved?
A: At the time of general contract bidding, the cost of waterproof construction is estimated to be about 10% of the total construction cost. Waterproof construction costs include underground waterproofing of buildings, roof waterproofing, and bathroom waterproofing. When the general contractor bids for the waterproofing project at the design stage of the construction drawing, the general contractor shall submit the request technically. The bidder shall provide the scheme according to their respective technical characteristics, and the total contractor shall use the total construction cost at the time of bid as the control basis. Due to the owner's supervision and the general contractor's responsibility for the quality of the project, the waterproofing cost is usually controlled at about 10% at the time of bidding, and will not drop substantially.
After the waterproof construction unit signs the contract with the general contractor, it strictly follows the contract to construct and pay for the project. According to the agreement, the project payment can be paid monthly, or once in three months. By the date of payment of the project, the total package will automatically transfer the payment to the waterproof construction unit. There is no question of asking for money.
Q: What material is used for this subway project? How much is the cost?
A: The subway project is a double-hole box-type cast-in-place concrete structure, which is controlled by the construction cost. The polyester tire modified bituminous membrane is selected for the bottom plate and the top plate, and the hot-melt method is used for the construction; the side wall is selected from the self-adhesive butyl rubber waterproofing membrane. The construction joint is a butyl steel composite waterstop.
The construction price of self-adhesive butyl rubber waterproofing membranes is approximately RMB 700 yuan, of which 20 to 30% are materials and accessories, and the rest are labor costs, management fees, and taxes. A skilled operator can build about 40 per day. Skilled workers earn about $200 a day (approximately RMB 1,600). The company's net profit is about 5-6% of the cost.
Q: How is the waterproof project repaired?
Answer: The state does not provide warranty period for waterproofing projects. All types of work are strictly constructed in accordance with the design requirements, and there is usually no leakage. However, since the guarantee of waterproof quality involves many factors, it is difficult to determine the cause of water leakage. It is possible that the concrete itself is not dense, and it is also possible that construction operations such as tying steel bars may cause damage to the waterproof layer. Once there is leakage water, the total package cost will be The waterproof company repairs, so there is no warranty issue. In other words: Waterproof material is not used to make up for concrete defects. Leakage is not just the cause of waterproof construction.
There is also a general contractor (or owner) requesting contractual guarantee of waterproof quality. Under this circumstance, the waterproof company will increase the risk of gold by 20 to 30% during the quotation. The warranty period is 3 to 5 years. Once there is a problem of water leakage, It is repaired by the waterproof company for free.
Q: Does the country have qualification requirements for the waterproof company, or technical personnel and performance requirements?
Answer: No. A waterproof company is registered as an ordinary company and is licensed by the Ministry of Land, Infrastructure, Transport and Tourism. The reputation of a company is the vitality of a company. In order to accept more projects, a waterproof company must have a good social reputation. If there is a failure in the construction of a waterproof project, no one will believe you in the future and will not undertake it in society. engineering. Therefore, the performance of the company is very important. If the waterproof company has a lot of major projects, the social recognition is good. It is also necessary to pay attention to cooperating with a famous large-scale general contracting unit. It also shows that your construction quality and technical level are relatively high, and it can also be of great help in undertaking business.
In order to enable companies to undertake complex and important waterproofing projects, the company must be equipped with high-level registered architects and engineers and other technical personnel, and there is a special design department for waterproofing design. Operators are also relatively fixed. In Japan, few people often change jobs. The company believes that such people are not stable and their work is not pragmatic. If a person changes his work, no unit will be hired, and only temporary workers or unsteady working hours will be used. The wages of temporary workers are so low that they cannot maintain the normal life of the family. Employees working in enterprises can be paid once a year. The older the salary is, the higher the salary is. Each position has a corresponding position salary. The salary is very high, and it is also very honorable. Therefore, it is difficult to qualify in Japan. Only the work is absolute. Those with serious and profound technical skills can compete in certain positions. Japanese companies also rarely expel people. If an employee is not suitable for formal work in the company, let him be a cleaner or a handyman unless you resign.
Employees working under this system are all doing their utmost to perform their duties. Serious work, recognized by the company and society, seems to be the meaning of each individual's survival.
- Visit to Tokyo Metro Waterproof Project
On the morning of June 9, 2006, heavy rain in Tokyo, the delegation visited the construction site of the Tokyo Metro. The subway is the last section of the Tokyo Metro. The construction of the subway is basically completed. It has reached the stage of laying the track, and only the station part of the waterproof construction is still underway. A total length of 9 kilometers, divided into 7 stations, up to 40 meters deep from the ground.
Japan's Taicang Chemical Co., Ltd. undertook waterproofing work at one of the stations, 20 meters deep from the ground, and used a cracked self-healing polymer cement-based waterproof coating, which was divided into four types of construction depending on the parts and functions used. Construction method.
In this section of the Tokyo Metro water-repellent project, Japan's Taicang Chemical Co., Ltd. used a spray method. First, about 200g/m2 of polyester cloth was nailed to the maintenance wall, and the polyester cloth was bonded with adhesive. The paint was then sprayed on the polyester cloth twice to form a 1.5mm thick waterproof layer. Since the polyester fabric is fixed on the retaining wall in a spot shape, the polyester fabric and the surrounding wall are empty, and the side sprayed with the waterproof coating is directly connected with the 1.2 m-thick main structure reinforced concrete to achieve close contact with the structure. The effect and form a complete closed waterproof layer.
The construction method has been used in Japan for about ten years and has a good waterproof effect.
Release date: 2006/9/5 16:59:44