As a supervisor, the following work should be done when supervising the project:
1, familiar with construction drawings, geological drilling reports, construction and acceptance specifications, and construction documents related to the project.
2. Organize the construction unit, design unit and construction unit to conduct the blue prints.the design to understand the engineering characteristics and design intent, as well as the quality requirements for key engineering parts. At the same time, in order to reduce errors in the drawings, the quality hidden dangers in the drawings will be nipped in the bud, thus reducing unnecessary losses and waste.
3. Check the qualification and construction permit of the construction unit.
4, review the construction organization design and construction scheme of the construction unit is economical and reasonable, advanced technology, feasible technology, effective measures, whether there is a reliable quality control system and safety measures.
5. Check whether the quantity and main performance parameters of the mechanical equipment entered by the construction unit meet the construction needs and quality assurance requirements.
6, review and register the certificate of raw materials, use certificate, and witness the sampling inspection.
During the internship, I mainly participated in pile inspection under the guidance of the supervisor, and checked the dismantling of beam and floor templates, the binding and reinforcement of steel bars, the pouring of concrete and the construction drawings. My ability has improved a lot, especially my ability to read drawings.
The foundation of this project is bored pile. During the construction period, our supervision mainly includes the following aspects:
1, organize survey team to check all axes and pile positions before drilling.
2. Before drilling each pile, check the embedding position of the liners, and the center of the liners should overlap with the center, with the deviation controlled within 50mm; The buried depth of liners in cohesive soil should not be less than 1.0M, and that in sandy soil should not be less than1.5m. The mud level in liners should be kept above the groundwater level1.0m. ..
3, in the process of pore-forming, as the slurry for wall protection and slag discharge, its production and performance requirements are controlled according to the following standards:
1) Clear water should be injected when the hole is formed in cohesive soil, and the undisturbed soil should be used to make slurry to protect the wall. The specific gravity of circulating mud should be controlled at 1. 1- 1.3.
2) When forming holes in sandy soil and thick sand layer, mud should be prepared or mud balls should be put into the holes to make mud, and the specific gravity of mud should be controlled at 1.2- 1.3.
3) When forming holes in sandy pebble layer or soil layer prone to collapse, the specific gravity of mud should be increased to 1.3- 1.5.
4) In the process of pore formation, the specific gravity of mud, viscosity, sand content and colloid rate should be determined frequently. Its control indexes are: the specific gravity of mud is less than1.25; Viscosity 18-22S~ sand content is not greater than; The colloid rate is not less than 90%.
4. In order to ensure the verticality of the hole, the drilling rig should be equipped with a guide device (drill pipe pressurized positive circulation rotary drilling rig), and a guide ring should be added every 2M in the drilling tool, and the total number of guide rings should be no less than two. The allowable deviation of verticality is controlled within 65438 0%.
5. Rock entry control: In order to control the quality of bored piles, the supervision team will take 24-hour shift measures to keep abreast of pile formation. In the process control, firstly, the construction unit is required to inform the supervisor and the owner whether the measured hole depth is consistent with the elevation provided by the drilling data and take rock samples when the drill pipe footage reaches this depth according to the rock surface elevation provided by the geological drilling report. If the rock sample is inconsistent with the drilling data, continue drilling until the rock sample is taken out, then the depth is measured by the supervisor, and the excess part is signed by the supervisor on site for confirmation, and finally the hole is formed according to the design requirements. Otherwise it will not be accepted.
6. Control of footage after rock entry: the construction unit is required to make drilling records every hour after rock entry, and judge whether there is weak interlayer according to footage records. If there is interlayer, drilling should be continued to ensure that the pile end enters the bearing stratum to meet the design requirements.
7. Final hole control: According to the geological report and field drilling records, the final hole can only be completed after the engineering pile enters the rock stratum required by the design unit. After finishing the hole, measure the hole depth with a measuring rope, mark it on the measuring rope, take it to a fixed measuring ruler prepared in advance to check the hole depth, and then make a hole-forming record.
8, reinforcing cage acceptance; After the reinforcement cage is made, check whether the variety, diameter, quantity and length of reinforcement conform to the requirements of design drawings and specifications, and check whether the concrete protective layer pad is hung as required. At the same time, use a ruler to check the length of the lifting rope of the reinforcing cage to control the elevation of the pile top.
9. Laying reinforcing cage: Focus on controlling the verticality of reinforcing cage (≤ 1%) and the connection quality of two reinforcing cages.
10. sediment control: after the secondary hole cleaning is qualified by the self-inspection of the construction unit, notify the supervisor to measure the sediment thickness, and control the sediment thickness within lOOmm according to the design requirements. Unqualified, continue hole cleaning, qualified, allowing underwater concrete pouring.
1 1. Quality control of pouring underwater concrete: when pouring concrete, there should be enough concrete reserves first, so that the conduit can be buried more than 0.8M below the concrete surface at one time; Require the construction unit to measure the concrete pouring height, lift and dismantle the conduit in time to prevent the pile from being broken;
When lifting the conduit, it must be inserted repeatedly and lifted slowly to avoid quality defects in the pile body. Secondly, the last grouting quantity is controlled by the pre-made control scale, and the height of over-grouting must be more than 500mm above the design elevation. For the submerged part that should be chiseled away, it is necessary to ensure that the exposed pile top concrete reaches the strength design value and the design elevation. In the concrete pouring process of each pile, a group of concrete specimens are randomly sampled and retained to check the concrete strength of the pile body. Supervise the whole process of pouring underwater concrete.
12. During the construction of bored pile, the content and completion of the construction on that day shall be recorded in the supervision log in detail every day, and a comparison chart between the planned progress and the actual progress shall be drawn to find out the reasons for being ahead of or behind, and timely rectification shall be made to ensure the smooth realization of the construction period.
13, organize the implementation of pile foundation quality inspection.
The most work we do on the construction site is to inspect the steel bars, and the premise of doing this work well is to read the drawings. Therefore, during the internship these days, we have seen many drawings, especially the structural construction drawings. If there is something we don't understand or understand, we will discuss it with each other or consult the website builder. After a few days, I can basically read the drawings. After getting familiar with and understanding the drawings, we will go to the site to check the steel bars. The shape and size of steel bar processing must meet the design requirements. Steel surface should be clean and free from damage, and oil stain and rust should be removed before use. Steel bars with granular or flaky old rust shall not be used. When inspecting steel bars, check whether the grade, diameter, shape, size and quantity of finished steel bars are consistent with the ingredient list, study the coordination order of steel bar installation and related types of work, and prepare the wire, binding tools and binding frame for binding. In order to shorten the construction period of steel bar installation and reduce the aerial work in steel bar construction, when transportation and hoisting conditions permit, the installation of steel bar mesh and steel bar skeleton should adopt the method of prefabrication and binding before installation as far as possible. The procedure of steel bar binding is: drawing lines, placing steel bars, threading hoops, installing cushion blocks, etc. Pay attention to the spacing and quantity when drawing lines, and indicate the position of encryption hoop. Generally, the order of reinforcement of slab is to arrange the main reinforcement first, and the negative reinforcement in the back row; In general, the longitudinal reinforcement is arranged for the beam first. Steel bars with welded joints and binding joints shall meet the specification requirements. Variable cross-section stirrups should be arranged clearly, and then longitudinal reinforcement should be installed.
Steel binding shall meet the following requirements:
1. The intersection of steel bars shall be fastened with iron wire.
2. Except for the intersection of two rows of steel bars near the periphery, the steel mesh of plates and walls can be fastened alternately, but the stressed steel bars shall not be displaced. Two-way stress of steel mesh, all must be fastened.
3. The steel bars of beams and columns shall be arranged vertically with the stressed steel bars, unless there are special design requirements. Stirrup hook lap, should be staggered along the direction of reinforced. The stirrup hooks of the beam are staggered about 50% on the beam surface, and the stirrup hooks of the column are staggered at the four corners of the column.
4. When the vertical steel bars in the column overlap, the hooks of the corner steel bars should form a 45-degree angle with the formwork (the polygonal column is the internal angle of the formwork).
Angle of bisection: the tangent of the cylinder and the column template is perpendicular): the hook of the middle reinforcement should be 90 degrees with the template. If a small cross-section column is poured with an internal vibrator, the angle between the hook and the formwork should be at least 15 degrees.
5. At the intersection of plate, secondary beam and main beam, the steel bar of plate is above, the steel bar of secondary beam is in the middle and the steel bar of main beam is below; When there is a ring beam or cushion beam, the reinforcement of the main beam is on the floor.
In the process of checking the steel bars, we saw that there was a post-pouring belt on the floor of the factory building, and then we learned about the post-pouring belt from the construction party. Post-pouring belt, also known as building post-pouring belt. According to the function, it can be divided into three types: the post-pouring belt is used to solve the differential settlement between the high-rise main body and the low-rise podium; The post-pouring shrinkage zone is used to solve the shrinkage deformation of reinforced concrete; The area used to solve the temperature stress of concrete is called post-pouring temperature area. Separation method of both sides of post-pouring belt. Both sides of post-cast strip shall be separated by lead wire mesh or single-layer steel mesh of steel support. The diameter and spacing of steel bars of steel corbel depend on the section size of members. Based on the principle of supporting stability, the mesh of lead wire mesh should not be too large to avoid slurry leakage when pouring concrete. If the mesh is too large, a layer of plastic film can be pasted outside the mesh to fix the support, so as to bear the extrusion force when pouring concrete and ensure no slurry leakage. After the concrete is solidified, the film can be torn off. The position of post-cast strip should be selected in the part with less stress on the structure, generally near the anti-bending point of the deformation joint of beam and slab, where the bending moment and shear force are not large; Can also be selected in the middle of the beam and plate, where the bending moment is large but the shear force is small. In the post-pouring zone under construction, although the concrete is post-poured, the steel bars cannot be broken. If the beam-slab span is not large, it can be reinforced at one time; If the span is large, it can be disconnected according to regulations and welded before the concrete is completed. The reinforcement of post-cast strip should be able to withstand the internal force caused by uneven settlement after concrete pouring into a whole, which can generally be calculated as internal force according to uneven settlement deformation and strengthened in reinforcement. The width of post-cast strip should be considered to be convenient for construction operation, and determined according to the structural requirements. Generally, the width is 700- 1000 mm, and the factory floor adopts post-cast shrinkage zone.
A month of intense internship is over, and I still have a lot of gains this month. It is necessary to sum up after the internship. Through a month's internship and practice, I learned a lot of practical knowledge. The so-called practice is the only criterion for testing truth. Through close observation, I learned a lot of practical and concrete construction knowledge, which I seldom contact and pay attention to at school, but it is very important basic knowledge.
Through practice, I have a deeper and more real understanding of the construction industry, which is a process of combining theory with practice. I also deeply feel the importance of construction workers' work, which is an indispensable occupation in the construction industry. The implementation of builder's work is conducive to improving the scientific level of investment decision-making in construction projects, prompting contractors to ensure the quality and safety of construction projects, maximizing the investment benefits of pilot construction projects and promoting the development of construction projects in China. Form a group of professional and socialized construction enterprises and engineers, connect with the international community and go to the world.
I found many shortcomings during my internship and need to strengthen my study. In the field of engineering, new technologies, new processes and new materials emerge one after another, engineering technical standards and schemes are constantly updated, and information technology is changing with each passing day. All these require me to keep learning, improve my professional quality and moral quality, be a qualified engineer, provide better service for the construction unit and make more contributions to the country.