Requesting 20 construction site internship diaries. The construction site process has reached the second floor of the ground, laying out wires, and removing formwork.

It was rainy on December 28, 2005

At three o'clock in the afternoon, after half an hour's driving (starting from Tianhe), we finally arrived at the construction site where the internship will be held - Guangzhou Baiyun Golf Flowers Yuannan District has a huge star. The construction area of ??the project is 55,209 square meters, with one underground floor, Building A with 17 floors, Building BC with 25 floors, and Building D with 10 floors. In the plan, the two main buildings BC are in the middle, and the two auxiliary buildings are arranged symmetrically on both sides.

When I first arrived at the construction site living area, I looked around and saw that the construction workers’ residences, canteens, bathrooms, construction site offices, and building material storage and processing areas were all in order as shown on the drawings. People and cars on the ground went their own way, and everything was going on in an orderly manner. These things shocked me a bit. Although I have been studying in college for more than three years and have learned a lot about the arrangement of construction sites, this is the first time I have observed such an organized construction site so close. After all, the construction site in my impression is still the kind of old construction site that is messy and disorganized, where the workers live in shabby places, the food is very poor, and people urinating and defecating everywhere.

What excites me even more is the project about to be an internship. Wear a safety helmet and follow Mr. Wu into the site, pass by the floors filled with various facilities and templates, and then step on the scaffolding in mid-air to the working surface on the top of the seventh floor. This is the world of steel bars, concrete and formwork. Some workers are tying the shear wall steel bars, while others are tying the wall support formwork with the shear wall steel bars. It can be seen from the scene that the project is a shear wall structure. There is no traditional column on it. It is replaced by cast-in-place concrete walls. Of course, some parts still have the shadow of columns, but it is also based on the Appears in the form of special-shaped columns.

Gong Wu introduced me to the general situation of the construction site and the safety matters that should be paid attention to, and arranged for the construction workers to practice at the construction site. We left the construction site and made the next step of internship life arrangements.

It was cloudy and sunny on Thursday, December 29, 2005

As I stepped off the morning bus out of the university town, I suddenly realized that the morning was a bit gray without yesterday’s drizzle. From time to time, you can feel the sunshine that warms your heart and lungs, and breathe the fresh air at the foot of Baiyun Mountain. Everything is so pleasant.

The difference from yesterday is that today I went to the meeting alone and broke into the construction site (because the construction site starts work at 7 a.m., and my morning bus does not leave until 7 o'clock, so I can only arrive at 8 o'clock at the earliest ). When I walked up the stairs along yesterday's route and was about to reach the top floor, I found that the support in front of me was blocking my way. It was dark inside, so I could only go around the other building and go up. When I got to the top, I discovered that it was still possible to walk through the support. This may be because I have never been on a construction site and am too inexperienced.

The construction site is complex but not chaotic, tense and orderly. Pouring concrete, tying steel bars (with embedded pipes embedded in them) and supporting the formwork are divided into three areas and carried out simultaneously in a streamlined manner. When I first arrived at the construction site, I was very interested in all types of work. I looked around, one step east and one west, but I couldn't see any way out. But the construction site still gave me a lot of feelings.

The speed is amazing. On the floor where the shear walls were poured yesterday, today the beam reinforcements have been laid out and tied.

The production of shear wall formwork is carried out on the entire wall, rather than in sections, and it does not use a lifting formwork system. Perhaps this is more reasonable.

There are strict requirements on the distance between the stirrups and the direction of the hook.

The anchoring length of steel bars is also very particular.

It was cloudy on Friday, December 30, 2005

In order to watch the wire laying, I rushed to the construction site at 7 o'clock in the morning. The construction workers were working on the two buildings on the east side (CD two buildings) floor to proceed. The general principle is to position the large frame of the exterior wall first, and then position the walls of the room corridors inside according to the exterior wall line. But there are a lot of little tricks involved.

The two buildings on the west side are in the process of laying out and tying beam and plate steel bars. Generally, the distance and size of the steel bars are marked on the board with chalk according to the drawings, and then the workers arrange the steel bars to the corresponding positions. The bottom bars must be such that the long bars are on top and the short bars are on the bottom, and both ends must extend into the corresponding positions of the wall or beam to ensure the anchoring force. During the construction process, I found that the length and direction of a small part of the bottom ribs were reversed. I wanted to adjust it at that time, but due to the construction order, adjustment would require extensive rework, so I didn't make the adjustment.

Before laying out the plate reinforcements, tie the beam's steel bars and use tools to place them into the beam formwork. The stirrups of the beams need to be tied firmly, and the spacing is also very strict. The two ends are denser (the shear force is greater), and the ones in the middle are relatively sparse, and the number is also clearly specified. When the stirrups shift during the construction process, they must be adjusted, and sometimes the beams even have to be lifted up and re-tied. In order to ensure the mutual position between the stress-bearing bars, waist bars, and erecting bars of the beam, as well as to ensure the thickness of the protective layer, some auxiliary steel bars are usually welded.

December 31, 2005, Saturday, cloudy day

Concrete was poured on the formwork of the floor slabs and beam steel bars that were tied yesterday.

The purpose of wetting the floor slab with water before pouring the concrete is to prevent the dry formwork from absorbing the lake soil so that the cement cannot obtain enough water for full hydration, resulting in pitted surfaces, honeycombs, holes and other undesirable phenomena. The concrete of slabs and beams is all pumped by pumps, and the recoil force is quite large. In addition to the support of the formwork, I did not see any special measures taken by the workers to avoid lateral movement of the wall or excessive stress.

Due to construction needs, comprehensive scaffolding is being constructed on the ninth and tenth floors. At the same time, due to the work sequence, the ironwork teams in Buildings A and B had a day off.

January 1, 2006, Saturday, cloudy day

Today, the eighth floor of Building A is tied with shear wall steel bars, Building BC is poured with concrete beams and slabs, and Building D is undergoing floor maintenance. Commercial concrete is used for pouring beam-slab concrete. The concrete is first transported from the concrete mixing station by a transport truck, and then delivered to the working surface by a high-pressure pump.

In order to meet the needs of the internship, we borrowed a digital camera to take pictures of some actual conditions at the construction site. The project adopts a flow-based construction plan, and you can see different types of work constructing on different working surfaces at the same time. In order to take more photos, we ran around the construction site all day long, took a lot of photos, and discovered a lot of interesting things.

Partition wall masonry

The project adopts flowing construction. When the floors are built to the eighth or ninth floor, various types of work on the decoration and decoration of the ground floor and water and electricity installation are gradually carried out.

We also specially observed the construction of the inner wall and found that the workers thoroughly followed the construction principles of brick walls during the actual operation: horizontal and vertical, full mortar, proper assembly, and reliable joints. in principle. For the construction of partition walls, stair handrails, etc., workers first use hanging and ink lines to position and lay the walls vertically and horizontally according to the dimensions determined by the builder. The interior partition walls of this project are constructed using a mixture of hollow concrete blocks and gray sand bricks. Among them, hollow concrete blocks are used as the main filling material, and lime sand bricks are used as auxiliary materials. When the space is not sufficient to lay out hollow concrete blocks, lime-sand bricks are used, especially when they are built close to the beams and slabs. At this time, only smaller blocks can be used to ensure the fullness of the mortar.

The embedded parts "moved", the shear wall suffered, and the workers were tired

During the process of taking photos, I suddenly heard bursts of violent hammer blows coming from a nearby room. The sound is surprising. So a few of us walked over to see what was going on. When we asked, it turned out that the workers were hammering on the shear wall to find the location of the reserved holes. In order to repair the buried pipes that were blocked during the pouring of concrete. (As for the quality of embedded pipes, I have always doubted whether its workmanship can perfectly achieve its intended purpose. I once asked the builder about this question, but the answer he gave me was: If the pipe is found after pouring the soil If the damage affects the use, the only way is to break up the concrete and re-lay it. It’s just that the processing area is different for different types of pipes. If it is a water pipe, it is more troublesome than a wire pipe). It is a method often used in construction, but it had no effect this time. The construction workers originally wanted to use a hammer drill to detect, but they did not use it because they were afraid of damaging the wall. The reason this time may be that the cement has filled the pipe, or the pipe is too far away! If it is the latter, I think we should directly cut out the pre-designed part of the pipe and add a pipe, and then pour it. However, such consequences may affect the crack resistance of the wall.

Personally, I think there are probably the following reasons for wall damage:

1. The embedded parts are not tied firmly. Usually the embedded parts must be tied firmly to the steel bars with tie wires. The net or template may be offset because it is not strong enough.

2. There is a problem with the quality of the embedded parts themselves. Maybe it is because there is a problem with the quality of the embedded parts themselves. Their strength cannot meet the needs of the construction, and they are damaged when the soil is poured.

3. Failure to take protective measures when pouring soil. During the construction of pouring soil, workers used excessive force to make the concrete dense, which caused the embedded parts to be damaged or moved to the predetermined position.

"Fake reporter", causing false alarm

When we were taking pictures of the mixer, the workers on site hurriedly asked me what I wanted to do, and hurriedly opened the electric box cover superior. His nervous behavior made me feel confused and confused. A few minutes later, they hurriedly greeted the manager, looking extremely nervous. Fortunately, one of the managers recognized me and told him the reason. They called us over and told us not to take random photos at the construction site. If we wanted to take photos, we had to ask a construction worker to provide guidance. It would be difficult to handle if we were mistaken for reporters. After being told this, I also woke up. Relevant departments now impose relatively severe penalties on irregularities in construction, ranging from fines for minor cases to suspension of work and fines for serious cases. The income of workers themselves will also be greatly affected after the shutdown. Of course, irregular operations cannot be blamed unilaterally on one aspect. After all, things are caused by most factors.

Every intern should pay attention to details on the construction site. Perhaps a small unintentional act may cause a series of adverse consequences. Of course, being cautious does not mean being timid, but it is especially important to be extra careful.

Sunday, January 2, 2006 will be sunny

"Letting go" to test the water

It's still the same as before, I got up at six o'clock and took the first bus to the construction site . Follow the construction workers to lay out wires for shear walls and door openings. Then, he asked me to go with him to "Pingshui" on the fifth floor. I was confused when I first heard the word "flat water". When I arrived at the scene, I realized that the horizontal line was being positioned.

During the on-site construction, the construction worker asked me if I wanted to give it a try. There was no reason not to try out such a good opportunity, so I agreed without hesitation. So I had another opportunity to practice. The operation of the level has been done in school, but there are few opportunities for actual operation. The level of proficiency can be imagined. In fact, many mistakes were made during the operation.

Mistake 1. When observing the baseline, instead of placing the lower end of the ruler against the baseline, adjust the ruler thinking of an integer. This is an obvious conceptual lack of clarity. Fortunately, the construction worker brought it up to me in time.

Mistake 2. When the crosshairs are blurred, you fail to use the eyepiece in time to adjust the clarity.

I see "flat water"

"Flat water" actually refers to the standard horizontal elevation leading to the wall to be constructed. That is to draw a horizontal line on the wall that is extremely meaningful for construction positioning. Under normal circumstances, it is taken one meter high from the floor. Of course, this must be brought up from the level point on the first floor.

"Leveling water" is actually a typical application of a level in actual operation. The process of leveling water begins with selecting a measuring station. The selection of the measuring station should ensure that the line of sight between the standard level point and the measuring station and the measuring station and the wall to be "flat" is unobstructed, and that as many walls as possible can be measured at one time. Then, set up the level, adjust the level, focus, and read the ruler. Then, according to the readings and the level, guide the level points to other walls and mark them with a red pencil (usually two points are drawn on each wall, one on both sides of the wall). Finally, use two points and one line to play the ink line.

Tips for ejecting ink lines

Usually the thickness of the ink line can show the proficiency of a constructor in laying out the line. The line ejected by an excellent constructor is thin, clear and accurate. There is a small method to make the ink line thin and clear:

a. Pull the newly burned ink line out of the ink fountain, tighten it in the air, and then flick it gently. This can pop out excess ink from the ink rope, thereby preventing the pop-up ink line from becoming too thick.

b. When popping the ink line, tighten the ink rope hard so that the pop-up line can be thin and clear.

The concrete slab expanded after solidification

Today, when I followed the construction workers to check the poured concrete floor, I found that one slab of concrete expanded outward. 2cm, the wall reinforcement of the shear wall on the edge also deviates outward from its original position by 2cm, that is, the wall reinforcement is on the edge of the original exterior wall. The reasons are:

The lateral support of the formwork is not stable enough, and excessive lateral force is generated when pouring concrete, causing lateral displacement, causing the steel bars and walls to deviate from the predetermined position.

The dimensions of the prototype were not accurately measured during construction.

The treatment methods are:

Even when supporting the upper wall formwork and pouring, correct the positions of the steel bars and shear walls

If it affects the appearance during the decoration stage When the size requires, part of the steel bars can be chiseled away, but the steel bars must not be damaged. This kind of processing is widely used in practical engineering. The constructor said that in theory it affects the protection of steel bars, but the impact of local treatment on the overall situation is still quite small.

Sunday, January 3, 2006 Sunny

Installation of formwork

Buildings A and B will install formwork today as planned. Building B is installing interior supports and slab formwork. Building A is in the process of tying the shear wall steel bars and installing the wall formwork.

To install the shear wall formwork, first place the lines according to the drawings, and the carpenters will nail the plates that fix the wall formwork according to the placed lines (the wall thickness is 200, the thickness of the formwork is about 20mm, the left and right sides The distance between the lines of the blocks is 240mm); then the templates are spliced ??according to the drawings of the shear wall. The distance during pouring of the shear wall is controlled by a steel bar 200mm long that is tied to the shear wall reinforcement and is vertically connected to the shear wall. The outward expansion of the shear wall is controlled by tension bolts and external The formwork support is used to ensure that the external diagonal support is more to ensure the verticality of the wall.

Monday, January 4, 2006 Sunny

Today, the second and third floors of Buildings C and D are undergoing wall dusting, floor tile paving and water and electricity installation.

Wall fan ash

The history of fan ash has a long history and the technology is extremely mature. But I always feel that the effect of fanning mainly depends on the skills of the workers and their own feelings. When discussing this issue with other students, one student said that if you use a template to make it, it can be formed quickly and beautifully in one go. I personally think that this method can be implemented using alternative methods, but it is still quite difficult to actually operate in a cast-in-place concrete shear wall structure.

The beams and plates of the structure change greatly, making the molding difficult, and the cost will inevitably increase. Thankless! Maybe you think that the structural layer and cushion layer are formed at one time when pouring the beam formwork.

But this is not realistic. After all, the structural layer and the cushion layer are made of different materials, which will cause mutual penetration and mixing of materials during pouring. Although the mutual adhesion force is relatively large, it is difficult to achieve a very reasonable effect.

There is a more or less certain bonding force between the concrete and the formwork, so it is difficult to form a smooth surface on the formed wall.

If formwork construction is used after the structural layer is completed, the construction will become more cumbersome, and it will be difficult to pour concrete slurry at the corners. It is also difficult to form a smooth surface.

For fan ash, templates are used, which adds one more layer of process. The effect is not good and the cost is high, which is unreasonable. And in China, a country with countless cheap labor, too much mechanization may not be a good thing.

Traditional steps for dusting

First sprinkle a certain amount of water on the wall to be dusted to make the wall moist, but the amount must be controlled. If it is too much, the mud on the wall will become more moist, more fluid and fall off. Too little will also affect the bonding force between the mud and the wall. The reason is that hydration of the concrete during the solidification process requires a certain amount of water to achieve good final strength and form a strong bonding surface.

Fixed point. In fact, you first use concrete mortar to make several protruding points on the wall, and the outer plane is the final position of the wall.

Apply concrete mortar to the wall fan so that it is as close as possible to the fixed point. If the mortar is too wet, sprinkle some dry cement powder over it. From time to time, flat wooden strips were used to smooth the walls.

When concrete mortar covers the wall, it is usually sprinkled with a layer of cement powder, and then the wall is smoothed with square wooden strips.

When the dusting process is completed, of course, subsequent maintenance is essential.

Laying floor tiles

The process of laying floor tiles is usually as follows:

Determine the height of the floor tiles and position them with fibers.

Put a certain amount of concrete on the lower surface of the bricks (the standard is that the height of the bricks after they are laid reaches the desired position, and the concrete under the bricks can be dense without causing too many holes) Pulp.

Lay floor tiles according to the positioning of the fibers, and the tile surface must be smooth.

Monday, January 5, 2006. Cloudy

The weather today is too cold. The shear walls are being poured on the floor, and our task is to do the leveling on the fifth floor.

Except that because the weather is too dark, it is difficult for the lights during construction to illuminate all places, and large lighting lamps are needed in some places. The other processes are the same as No. 2. Of course, our actual operation capabilities have also made greater progress than last time.

It will be cloudy on Tuesday, January 6, 2006

Wire hanging

The weather forecast shows that today’s cold weather has increased compared with yesterday, but the wire hanging is carried out upstairs. When we were reviewing the axis, we shivered from time to time under the blowing cold wind. It felt much colder than yesterday.

According to the construction worker, usually the deviation of the axis drawn upwards using glue lines and small hanging hammers is not large on the first floor, but when it is drawn upwards on the fourth or fifth floors, there may be a deviation of 4~5mm. , it may be even bigger when there is wind. This is when its accuracy will affect the quality of the project. Therefore, when building high-rise buildings, the axis must be rechecked every four or five floors, and any deviations must be corrected in a timely manner to avoid excessive errors that may bring safety hazards to the project.

Tools used for hanging wires: cylindrical hanging hammer weighing more than ten kilograms, thin steel wire (the hanging and hanging parts usually cannot be knotted), ruler, etc.

Step 1. Lead out a small piece of wood (square wooden strips are also acceptable) on the wall to be matched, and fix it to a point where it can bear the weight of the hanging hammer and remain stable.

2. Tie the iron wire to the fixed wooden block. The iron wire must be on the plane where the axis to be measured is located. The wire cannot touch any obstacles.

After the hanging wire is stable, use a ruler to measure the distance between the hanging wire and the lower positioning axis, and then draw the position of the upper axis based on the distance from the lower part.

Compare the distance between the review axis and the actual axis and make necessary adjustments.

During the measurement process on that day, it was found that there was no obvious difference in most of the axes. The upper center line of the only shear wall deviated from the axis by 3cm. The reason was that the upper formwork tilted inward during the construction process. At that time, the axis could only be drawn with ink lines to facilitate the adjustment of the subsequent construction of the upper part.

The self-raising process of the tower crane

I have been interested in lifts since I was a child. After listening to the teacher introduce the self-raising process of the crane in class, I have always wanted to find an opportunity to see it with my own eyes. See it in action. It just so happened that the attached crane used in the project I was doing my internship needed to be heightened today. (People at the construction site call it tower crane.)

Looking at the construction surface, you can see that in addition to a driver in the cab, there are five workers on the tower crane, one of whom is responsible for the standard section. The other four workers are responsible for connecting and fixing the lower part of the standard section to the tower body. First, the worker opens the handrails of the rack and is ready. The tower crane will lift the standard section to the frame position. At this time, the workers above connect the standard section lanyard to the trolley hook of the ferry guide above the rack. And loosen the bolts between the transition section and the tower body standard section.

Then start the jack to lift the frame and its upper structure beyond the height of one standard section. Push the standard section into the frame and place it in the corresponding position. Each of the four workers below is responsible for fixing an angle bolt, and the upper worker is responsible for the other. Various processes on the upper part quickly connect and fix the standard sections. Then, retract the jack and prepare for the installation of the next standard section.

After all the standard sections in the plan are installed, the upper structure is fixed and one-time self-lifting is completed.

January 7, 2006 Overcast

Today’s project includes placing beam reinforcements, tying plate reinforcements, supporting formwork, and installing external scaffolding. Install embedded pipes.

For steel bar projects, placing beam bars is a relatively difficult construction process. Although you can say that they are actually very simple things, as long as you have the strength to do them. But in fact, brute force is not enough. The weight of the beam bars will become very heavy after they are tied on the formwork. You need to put them in the corresponding positions evenly. Several or even dozens of people can use force at the same time to put the beam bars in the corresponding positions. And ensure that the mutual positions of various steel bars such as stirrups and beam main bars do not exceed the requirements of the specification. After the beam reinforcement was placed in the morning, the beam reinforcement at a corner happened to move too much, and the stirrups on it rotated, and had to be lifted up and re-tied. When placing beam reinforcements, attention should also be paid to protecting the embedded parts, as sometimes it may even be difficult to place them. You will have to make reasonable adjustments.

January 8, 2006, overcast

Today’s construction includes pouring soil, supporting formwork, and installing embedded pipes.

I don’t think it is difficult to lay out buried pipes. But I often doubt its quality. I suspect that the probability of it being damaged during the actual construction process is too great, and I always feel that it cannot withstand the damage caused to it by construction. What I am more worried about is how painful the consequences will be once problems occur during actual use. (Perhaps the frequent blockages in the sewers in my home have given me too much of a shadow.) In fact, buried pipes are often damaged in actual projects. The sewer pipe that appeared a few days ago was blocked by concrete and was blocked from the second floor to the third floor. When it comes to quality assurance of embedded pipelines, I think there are three aspects that should be paid great attention to.

The quality of the pipeline must be guaranteed.

The layout, connection and binding of pipes must be firm and reasonable.

Protect the embedded pipes when pouring the soil

Overcast on January 9, 2006

Today’s work includes tying shear wall steel bars , support formwork, and install embedded pipes.

There is a difference between shear wall steel bars and plate steel bars. One more thing is that a lot of steel bars (vertical wall bars with a diameter greater than 10mm) need to be welded (mostly butt welding.) . Stirrups need to be added on both sides and corners of the shear wall.

January 10, 2006 Overcast

In order to enhance the impression of the construction, we used the camera to take more photos. Many detailed issues were also discovered during this process.

For example, the discovery of template cracks and their treatment methods. The constructor said that if there are small cracks in the board, some paper pads can often be used to meet the construction requirements.

For example, bamboo poles can be used to separate floor slabs of different thicknesses during the pouring of concrete floors.

For example, small components such as concrete protective layer blocks and steel bars play a role in fixing the steel bars.

January 11, 2006 Sunny

The most unexpected thing today was seeing a project rectification notice. The content of the notice has two aspects, one is the physical quality of the project, and the other is safe and civilized construction.

Regarding the quality of project entities, there are some detailed issues! In fact, the guarantee of project quality lies in the details! The main contents are:

Formwork engineering: column heads are not vertical and deformed, the shear wall formwork interface is not tight, and there is leakage of paddles.

Reinforcement installation: no protective layer blocks are hung on the upper part of columns and shear walls; the distance between floor steel bars and beam edges is different.

Brick wall construction: wall top arching should not be done too early Masonry should be carried out seven days after the lower wall is completed; the brick joints of the first floor brick wall are not saturated with grout; the first and second floor columns and shear wall component surfaces are deformed and uneven.

Renovation project: There are cracks in some wall surfaces

Water and electricity installation: The reserved openings for wire pipes are not in the correct position on the wall; the brick wall and shear surface of the same room are The wires are not connected at the same elevation.

There is also a lot of content about civilized construction:

Exterior grille: the safety net is not hung tightly, the corner is too far from the wall, and bamboo is not added, and the bamboo is laid flat It is too sparse and the binding is not strong, and the debris in the grate cannot be cleaned.

Electricity for construction: There is no door to switch the electrical box (this problem was taken when the photo was taken for the first time, no wonder they were so nervous at the time.). The electric saw does not have a saw tail or protective cover, the electric welding machine does not have a protective cover and the wires are randomly connected, and the electrical box has no number or wiring diagram.

This notice lets me know where to start during future internships and what the key points are.

Sunny, January 12, 2006

Today is the last day of my planned internship.

I still came to the construction site as usual, but I had no plan to see anything engineering. I just said goodbye to the engineer who took me and the workers I was familiar with, and gave them the photos I took for them. And stamp what needs to be stamped (is it good to start well!)!

In these short 20 days, I have given something and gained something. But the deepest experience is that true knowledge comes from practice! I believe that this internship will bring a lot of help to my future work life.

This internship will become a wonderful memory for me in the future!

Thanks to the teachers, classmates and friends on the construction site who cared about me and helped me during the internship!