Internship report
05 supervision
In this internship cours《建设工程监理》, five of us were assigned to Gaoxin Supervision Co., Ltd. The project site is located in Xiadu Street, north of Sun Yat-sen University, Haizhu District, Guangzhou. The construction unit is Guangzhou Gaopai Real Estate Investment Co., Ltd., the commencement date of the project starts from March 30, 2018, and the completion date is expected to be October 30, 2018. The construction unit is in charge of Guangzhou New South Fire Protection Engineering Co., Ltd., and the project structure is frame structure with a total height of 31 floors.
By the time we arrived at the construction site, the foundation engineering had been completed and the main structure had been built to the 23rd floor. On the day of arrival, we got a certain understanding of the project under the narration of Chen Gong, learned about the construction progress and the current basic situation of the project, and also roughly read the documents, supervision logs, project inspection scores and other materials about the matters that the supervision unit should be responsible for, and basically understood the most basic operating procedures of the supervision party.
That afternoon happened to be a regular meeting once a week, and another colleague and I made minutes of the meeting. Knowing the procedure of the regular meeting, the person in charge of the construction unit began to report the construction progress last week and the problems found in the construction process. For example, when the main structure is built to the 23rd floor, it swings to the 7th floor, and bricklaying to the 11th floor, the main problems found are: there are problems and gaps in formwork installation, which will lead to slurry leakage during concrete pouring and eventually lead to common construction problems such as &”;honeycomb and pits&”;, which will seriously affect the progress and quality of the project; There are some problems in bricklaying, such as uneven wall surface, high side and low side, no seam in bricklaying, non-vertical wall surface, wide side and narrow side; There are also workers who waste materials in construction, which is mainly reflected in the fact that when carrying bricks, they break them, and the template is not cut according to actual needs, which leads to waste. Then, the person in charge of the supervision party described the situation. The general content was that the overall construction was good last week, but the shortcomings were that the basement material report had not been sent up yet, and there were potential safety hazards. Therefore, the procedure of applying for inspection at the advanced site of materials should be implemented, and the transportation speed of tower cranes should not be too fast. Finally, the representative of Party A put forward opinions and requirements on the issue. After the meeting, sort out the minutes of the meeting within 24 hours.
The next task is to know the drawings and learn how to view them. For example, what do the symbols on the drawings mean? What are the reinforcement and anchorage length of continuous beams and beams? When the size gap between the two beams is large, steel hangers should be placed in the middle of the beam to bear the load of the beam; Gluten is at the end of the board, and it should pass half of the gluten of the beam; The first-grade steel should be hooked in the lintel, and the second-grade steel lintel does not need to be hooked. The first time I saw butt welding and electroslag pressure welding of steel bars, it was required that the charge should be placed evenly, smooth after burning, and evenly covered, and the side should not be large and small.
In addition to knowing the drawings, the most important thing to go to the construction site is safety. Safety has always been the most important issue in construction and production, so we must pay strict attention to it. Usually, the common accidents in construction include falling from a height, object hitting, electric shock, mechanical injury, collapse, lifting injury, poisoning, suffocation, vehicle injury, fire and explosion.The first five types account for more than 80% of the total number of accidents, which are the so-called &”;five major injuries&”;. The so-called safe production refers to taking corresponding accident prevention and control measures to avoid personal injuries and property losses in the process of production and business activities, so as to ensure the personal safety of employees and avoid accidents. The vast majority of accidents are caused by illegal command, illegal operation, blind construction, and ignorance of pretending to understand. In addition, those who do not have certificates and take risks account for more than 80% of the total number of casualties.
Therefore, safety in production is always in the first place.
As a supervisor, you must be familiar with the project content first. From foundation excavation to project completion, the supervisor must stand by. Before the project starts, the supervision work should first edit the supervision plan, supervision implementation rules, side-by-side supervision plan and safety production license; Quality and safety management system structure, qualification certificates of management personnel and special operators, construction equipment and inspection report; Declaration procedures for quality and safety supervision. During the internship, I noticed that before the concrete truck sends the concrete to prepare for pouring, the supervisor checks in advance whether the concrete is qualified according to the label of the order and the departure time, and then draws concrete on site for slump test, and can only use it after it is qualified. Generally speaking, the materials are accepted before entering the site, and the unit responsible for the project must submit the inspection report to the supervision department as soon as possible. Samples should also be taken according to the sampling method specified in the document, and the number of samples taken must correspond to the specifications, batch numbers and quantities of materials entering the site, and witness records and inspection accounts should be kept; Collect the cement certificate, steel bar certificate, steel bar sign, and the furnace number on the steel bar certificate should be consistent with the steel bar sign, and the batch number on the cement and other materials certificate should be consistent with the batch number on the package.
In the process of inspection, the inspection of steel bars is particularly important. The cutting and binding of steel bars must be accepted according to the national standards. In this internship, electroslag pressure welding is the most contact for us. Electroslag pressure welding is suitable for the connection of vertical reinforced bars in cast-in-place concrete structures such as columns, walls and structures, and it is not allowed to be placed horizontally in beams, plates and other components after vertical welding. Before formal welding, the welding process test should be carried out first, and after passing the test, the formal production can be carried out. Before welding construction, rust spots, oil stains, sundries, etc. should be removed from the welding parts of the steel plate and the surface where the steel bar contacts the electrode. When the end of the steel bar is bent or twisted, it should be short-circuited or cut off. The welded furniture should have sufficient rigidity, be flexible to move under the maximum allowable load, and be convenient to operate. The voltmeter and time display should be fully equipped. Electroslag pressure welding construction process: 1. The upper and lower jaws of the welding fixture should be clamped on the upper and lower steel bars; Once the steel bar is clamped, it shall not shake; 2. Arc striking can be conducted by direct arc striking method or by iron wire ring (covered electrode core); 3. After the arc is ignited, the arc process should be carried out first, and then the feeding speed of the reinforcement should be d, so that the end face of the reinforcement is in contact with the liquid slag pool, which is transformed into an electroslag process. Finally, at the same time of power failure, the reinforcement is quickly pressed down, and molten metal and slag are extruded. After the joint is welded, it should be stopped for a while before the flux can be recovered and the welding fixture removed, and the welding package around it is sudden.The height of the rebar surface shall not be less than 4 mm. When welding rebar with different diameters, the axes of the upper and lower rebar shall be on the same straight line.
Summarizing this internship, I have benefited a lot. The best thing is that Chen Gong can personally guide us, and the content he tells is vivid and concise, which can be well accepted and mastered. He has learned a lot of professional knowledge that he can&;t learn in books, so that he finds that his existing knowledge is far from being applied to practice. In this industry, it is impossible to do it without enough experience accumulation. He must keep learning, so as to face problems flexibly, and he can be very familiar with relevant norms in order to complete the task well.
Experience of on-site training of building construction technology
According to the arrangement of the school, I went to the cost department of Guangzhou Zhuzheng Co., Ltd. for an internship on December 25, 2018. However, due to the teacher&;s consideration that the company will not send me to the construction site, I can&;t take this internship opportunity to learn more about the process operation on the site. Therefore, on January 3, 2018, I was transferred to Guangzhou Guangjun Engineering Supervision Co., Ltd. for an internship. This internship let me know the knowledge of cost and supervision, and let me further understand the difference between theory and practice.
In the internship project of Guangzhou Zhuzheng Consulting Co., Ltd., although I only helped our company to sort out the relevant information of various projects, I benefited a lot. For example, in the process of printing forms, I realized that I was very strange to the daily operating system of the office, and I felt that I should pay attention to learning some other professional knowledge to arm myself; In my spare time, I didn&;t take the initiative to ask Sister Lin, who led my internship, if she could help or coordinate the internship content with her, so I was too passive. When chatting with the staff of our company, I don&;t have the courage to express my inner thoughts, perhaps because I am afraid of saying something wrong and affecting the position of Sister Lin in the company. In the process of internship in our company, the biggest gain is to get to know ourselves again, knowing that I have not learned my professional knowledge well in my studies, but also lacked in my life.
The internship in Guangzhou Guangjun Engineering Supervision Co., Ltd. let me further understand the difference between the construction site and the classroom knowledge. I feel that my knowledge is too narrow and there are still many things to learn.
The construction site of my internship is the library of Guangdong Communications Vocational and Technical College.
A brief introduction to the project:
The library of Guangdong Communications Vocational and Technical College is located in Tianyuan Road, Tianhe District, Guangzhou, with a total construction area of 13,200m2, five floors above ground, a basement (semi-basement) with a plane size of 53 m×46m, an outdoor terrace of -0.45 m and the highest point of the roof of 26.45m.. The first floor is a multifunctional lecture hall, the second floor is a student study room, the third floor is a reading room, the fourth floor is a periodical reading room, and the fifth floor is a library. There are four escalators and two elevators in the room. There is a heavy rain canopy of about 310㎡ in the middle courtyard of the second floor. The foundation pile is static pressure high-strength prestressed pipe pile, and the structural beam adopts bonded and unbonded prestressed concrete technology. The roof adopts steel grid structure. The quality of the project is qualified, with an investment of more than 24.78 million yuan and a contract period of 201 calendar days..
The main participating units are: the construction unit: Guangdong Communications Vocational and Technical College.
Survey unit: Guangdong Geological Construction Engineering Survey Institute.
Design unit: Guangdong Construction Engineering Design Institute
Construction unit: Guangzhou Housing Construction and Development Co., Ltd.
Supervision unit: Guangzhou Guangjun Engineering Supervision Co., Ltd.
Second, the internship content:
1. Content of field practic: knows the basic situation of the site, construction survey, earthwork, supervision of base and foundation engineering, formwork engineering, reinforcement engineering, concrete engineering, masonry engineering, ground and floor engineering supervision, door and window engineering supervision, decoration engineering, roofing and underground waterproof engineering, acceptance procedures and methods of concealed works on site, and the system and problems solved at regular meetings.
2. Understand the information content of the construction site; (1) Information of the construction unit: construction organization design, construction contract documents, construction site record documents, construction acceptance documents, site communication documents and other documents; (2) Information of supervision unit: construction contract documents, entrusted supervision contracts, survey and design documents, detailed rules for supervision implementation, design disclosure and minutes of the joint review of drawings, etc.
Three internship gains and experiences:
First of all, internship is a familiar and unfamiliar word to me, because I have also experienced many internships in professional courses during my one-year college career, but this time it is so different. It not only allows me to learn professional knowledge, but also comprehensively tests my abilities in all aspects: study, life, mind, body, thought and so on. It is like a touchstone to test whether I can apply the theoretical knowledge I have learned to practice. It is related to whether I can stand in this challenging society in the future, and it is also the key to building my confidence, so my investment in it is also 100%! The short three-week internship life is over, and I have gained a lot in these internship days. It is necessary to sum up after the internship. Through the three-week internship practice, I learned a lot of practical knowledge. The so-called practice is the only criterion for testing truth. Through the side station, I observed the whole building construction process closely, and learned a lot of applicable concrete construction knowledge, which I seldom contact and pay attention to at school, but it is also very important basic knowledge.
Brother Wu Jianhua, who led our internship, was in the class of 2002 in our college. Now he works in Guangzhou Guangjun Engineering Supervision Company. During the internship, Brother Wu not only led me to the construction site to explain the relevant professional knowledge of the engineering process to us, but also constantly looked for opportunities to give us practical exercises, and often asked some basic knowledge questions. Every intern should not only form a relevant &”;knowledge network&”; in the classroom, but also dictate it one by one to exercise our oral ability, communication ability and expression ability.
For example, the causes of concrete cracks and their treatment methods! This is a very complicated problem, so let&;s talk about my opinion:
1. Causes of cracks:
There are many reasons for cracks in concrete, mainly temperature change and humidity change.Brittleness and inhomogeneity, unreasonable structure, unqualified raw materials (such as alkali aggregate reaction), template deformation, uneven settlement of foundation, etc.
During the hardening of concrete, the cement releases a lot of hydration heat, and the internal temperature rises continuously, causing tensile stress on the surface. In the later cooling process, due to the constraint of the base or hardened concrete, it can not shrink freely, and tensile stress will appear in the concrete. The decrease of air temperature will also cause great tensile stress on the concrete surface. When the tensile stress exceeds the tensile strength of concrete, cracks occur, which develop upward from the basement and even run through the whole foundation. The internal temperature of many concrete changes little or slowly, but the surface humidity may change greatly or dramatically. If the curing is not solid, sometimes it is dry and sometimes it is wet, and the surface shrinkage deformation is constrained by internal concrete, it often leads to poor crack resistance of cracked concrete. Due to uneven materials, unstable water-cement ratio and segregation during transportation and pouring, the tensile strength of the same fast concrete is uneven, and there are many weak parts with low tensile capacity and prone to cracks.
2. Measures to prevent cracks:
(1) Improve aggregate gradation, apply it to hard concrete, and add additives to reduce the amount of cement in concrete;
(2) When mixing concrete, add water or water to cool the crushed stone to reduce the pouring temperature of concrete;
(3) pouring concrete in hot weather is to reduce the pouring thickness and use the pouring level to dissipate heat;
(4) Burying water pipes in concrete, and cooling by cold water;
(5) A certain amount of ice cubes can be mixed in concrete;
(6) Provide a reasonable time for form removal, and conduct surface insulation when the temperature drops suddenly, so as to avoid a sharp temperature gradient on the concrete surface;
(7) Thermal insulation measures shall be taken for the surface of concrete pouring blocks or thin-walled structures exposed for a long time during construction in cold seasons;
(8) Improve the boundary constraint and structural design, such as reasonable analysis and pouring, setting sliding layer, avoiding stress concentration, setting buffer layer, reasonable reinforcement, setting stress relief groove, etc.
(9) Strengthen construction monitoring.
After each project is completed, cracks will inevitably occur, and the influencing factors are not only objective factors but also subjective factors. Usually, the technical level of concrete pouring workers is low, and their work is only gained by experience, so mistakes will inevitably occur in the construction process. Therefore, in the process of internship at the construction site, I feel that the actual and theoretical knowledge at the construction site is very different.
For example, the first step before pouring concrete is to clean up the sundries of the formwork, but in fact, there are sundries on every beam-column formwork, but because a few of them will not affect the strength of concrete, the construction unit usually does not make other treatment. Another example is that some steel bars are easily trampled, which makes some steel bars stay and deform, resulting in the phenomenon of steel bars exposed after casting and formwork removal. In this way, exposed steel bars will corrode when exposed to air for a long time, which will affect the strength of steel bars, the mechanical bearing capacity of plates and the structure of buildings.
Through field practic《建筑施工技术》&;s theory and method are applied to engineering practice.Let me further understand and master the technological process, construction methods, quality control standards, common quality defects and prevention in construction technology.
I hope the school can give us more opportunities to practice on the spot and enrich the knowledge we have learned.