What are the key processes in bridge construction? Key working procedures of bridge construction:
1, pile foundation construction → tie beam construction → column construction → capping beam construction → cushion stone construction;
2, box girder prefabrication and installation; 3. Bridge deck system engineering.
The general steps of bridge construction are as follows:
1, substructure construction; Generally, it includes foundation, pile cap and pier. If the pier is high, there are tie beams. If it is a simply supported beam, there should be a capping beam. If it is a continuous beam, there is generally no capping beam at the pier.
If the foundation construction is to expand the foundation, it needs an excavator to dig the foundation pit, then tie the steel bar and pour the concrete. For pile foundation, it is to drill holes, then go down to the reinforcing cage and pour concrete.
After the foundation is completed, tie the steel bar of the bearing platform and pour the concrete of the bearing platform. Then the pier construction is carried out, which is also to tie steel bars and pour concrete. Of course, templates are needed.
Then the bearing was buried.
2, the upper structure construction; There are two kinds of prefabricated and cast-in-place here. If it is prefabricated, the precast beam will be directly erected on the pier. If it is cast-in-place, it is necessary to tie steel bars and pour concrete. Prefabricated; After the beam is erected, it is usually necessary to pour wet joints or hinge joints. Then we are going to pave the bridge deck.
3. ancillary works; That is, guardrail, drainage, slope protection and so on. There is still a big difference between a highway bridge and a railway bridge.
What is the key process of water conservancy project supervision?
The supervision engineer shall carry out the supervision work according to the responsibilities and authority granted by the chief supervision engineer, who is the direct person in charge of the supervision work and is responsible to the chief supervision engineer. The main responsibilities shall include the following:
1 Participate in the preparation of supervision planning and supervision implementation rules.
2. Pre-examine the subcontracted projects and subcontractors proposed by the contractor.
3. The construction organization design, construction measures plan, construction progress plan and capital flow plan submitted by the pre-trial contractor.
4. Pre-examination or authorized issuance of construction drawings.
5. Check the original vouchers, test reports and other quality certificates of on-site materials, components and engineering equipment and their quality status.
6. To examine and approve the application report for commencement of divisional projects.
7. Assist the chief supervision engineer to coordinate the working relationship of all parties involved in the construction. Handle related problems on the construction site according to responsibilities and authorities, and issue general supervision documents.
Check the construction quality of the project and confirm or deny it.
9 Review the engineering survey data and original vouchers, and confirm the engineering survey results.
10 Pre-examine various payment vouchers.
1 1 Put forward preliminary opinions on modification, claim and handling of quality and safety accidents.
12 Participate in the project quality evaluation and acceptance according to the responsibilities and authorities.
13 collect, summarize and sort out supervision data, participate in writing supervision monthly report and fill in supervision log.
14 in case of major problems and emergencies during construction, report to the chief supervision engineer and ask for instructions in time.
15 to guide and check the work of the supervisor. If necessary, suggest to the chief supervision engineer to replace the supervision personnel.
Is reflow soldering the key process of *** t? Of course, the three processes of SMT are printing, mounting and reflow soldering. I hope it helps you.
What are the key processes of hanging basket construction?
1 0 support (bracket) construction;
2, bearing and temporary consolidation system construction;
3, hanging basket construction;
4, concrete pouring construction;
5. Prestressed construction;
6, beam alignment control;
7, closed section construction and system transformation
How to write the key working procedure We determine the working procedure that has great influence on the quality such as efficiency and reliability as the key working procedure to control.
What is the key process of diaphragm wall construction? In the construction of underground continuous wall, the shape of groove wall basically determines the shape of the wall, so the excavation accuracy of groove is one of the keys to ensure the quality of underground continuous wall. Therefore, grooving is the key process in the construction of underground continuous wall.
What effect will the radial runout of lathe spindle have on the machined parts? Influence of pure radial runout of spindle on parts processing
1) Influence on Boring Processing
When boring on a boring machine, the boring cutter rotates with the spindle of the boring machine. When the main shaft makes a pure radial jump, the shaft will make a simple harmonic vibration in a fixed direction. The shape of boring is determined by the trajectory of boring tool head in inertial coordinate system. Let the position of the boring tool head in the dynamic coordinate system be M=R and N=0, where r is the radius of the hole to be machined.
2) Influence on turning processing
When machining an excircle or boring on a lathe, the workpiece rotates with the spindle of the lathe. Therefore, the geometric shape of the machined surface of the workpiece is determined by the relative trajectory of the tool in the motion coordinate system. Let the coordinate position of the turning tool tip in the inertial coordinate system be Z=0 and y =-r, where r is the machining radius.
If ρ 1=R-Acosφ, ρ2=R-Acos(p+φ), then D=ρ 1+ρ2=2R, indicating that this centerline is an equidistant curve, that is, the cross-sectional geometry of the workpiece has no diameter error.
When φ=0, ρ=R-A, and φ = π, ρ = r+a. Therefore, O 1 is not the center of the actual contour of the end face of the workpiece after machining, and the distance from the center of the actual contour of the workpiece to O 1 is a.
Therefore, it can be concluded that when turning the inner and outer circles on the lathe, the radial runout of the spindle mainly affects the coaxiality error of the workpiece, and the influence on the roundness error of the workpiece can be ignored.
Is there a key process in stamping? Drawing, trimming and punching, flanging and shaping are all very important. Relatively speaking, drawing is the most important. Flanging and shaping are followed, trimming and punching are followed, and blanking is the last.
Requirements: The definition of key processes in a project is mainly determined by logical relations.
If the previous process can decide whether the later process is started.
Then this process is the key process.
Its performance is that the construction period of all key processes is the longest.