Experiences shared by a veteran technician

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After reading many posts from friends, I feel that there are many young people on this forum. Some might ask: Are you trying to act senior by relying on your age? How old are you? I’m not that experienced, but I’ve worked in construction for fifteen years; some of my friends have only been in this industry for two or three years, so the construction experience they talk about is really hard to believe. When I started working, our company was a state-owned enterprise, and there was still a hint of a planned economy at that time. We were working on a key project assigned by our superiors; there were no supervisors, only the construction management team from the client side. New graduates had to work in the work teams for one year first, as part of this probation period, before the company would officially accept them. I heard that older graduates (those who graduated in the 1960s) had to work in those teams for three to five years. At that time, all the workers in the company were permanent employees – there were no migrant workers – and the technical expertise was quite high. Later on, there were fewer engineering projects within the system; around 1993, companies began to enter the market, marking a shift from a situation where \"the daughter of an emperor never has to worry about finding a husband\" to the current situation in the construction industry where there is more competition than available opportunities. Like 99% of construction companies, it went through a difficult period; due to the heavy burdens common to state-owned enterprises and an outdated system, it was on the verge of bankruptcy. In recent years, it has gradually shown signs of improvement as a result of restructuring. Okay. Without further ado, I’d like to share some of my experiences in construction so that we can all learn from them.* What should technicians do at the construction site? For technicians, at the very least three things are required: being diligent with their hands, their feet, and their mouths. Being diligent with one’s hands means developing the habit of writing frequently and keeping good records. Being diligent with one’s feet means traveling more – to the site, to the supervisors, and also to the managers – first serving as a messenger before focusing on doing the actual work. Being talkative means talking more – explaining things to those below and reporting to managers about the fact that two college students majoring in civil engineering applied for jobs during that period (back then, jobs were assigned to us; there was no choice, but now one has to find a job on their own, though this has its advantages and disadvantages). They were very confident yet practical; they shared with me many lofty ideals and ambitions, and also expressed mild dissatisfaction regarding salary. I told them that they need to do their job well; if they want to make a living from it, they must stay calm, observe more, ask more questions, and be more cautious. They can use this experience as a stepping stone, but they must not take their work lightly. It’s okay not to understand, but you’re not allowed to act on your own without asking when you don’t know. When asked what a technician should do on the construction site, I told him: setting out measurements, preparing material plans, writing technical instructions, taking samples of raw materials brought to the site for testing, conducting on-site quality inspections, filling out documents related to concealed works, reviewing rebar cutting lists, checking the dimensions and elevations of formwork, and so on. But at first, he just needs to follow the tasks assigned by the site supervisor and complete them. Starting with setting out, after the dedicated surveyor has determined the main axis and established the elevation control points, the technician needs to master the basic skills of using plumb bobs; it’s not possible nor practical to rely solely on thetheodolite. Moreover, the process of positioning and setting out is much simpler in residential and office buildings, while it becomes much more complex in industrial factories. When measuring dimensions for radiation dosing, it is essential to avoid using a small ruler to take measurements step by step (3-meter and 5-meter rulers are commonly used on construction sites) to prevent errors from accumulating. Furthermore, when the height difference between the two points is large, calculating the slant distance and the height difference using the Pythagorean theorem generally results in a much smaller error. Remember the key points the teacher mentioned when teaching measurement: start with the overall view and then move on to the detailed parts ； Regular reviews are necessary; without reviewing the previous step, the next step cannot proceed ； Each step of the measurement must be verified. Surveying and setting out are particularly important during construction; even the slightest carelessness can result in significant financial losses. The surveying and setting out work at construction sites these days is not as systematic as it was during surveying exercises in school, where there were a front ruler, a back ruler, readings taken, and records made. Usually, only the site supervisor and a technician go to carry out this work, with a worker being called over on the spot to help – which is really inappropriate. You can’t expect the project manager to provide enough professionals to assist you with positioning, but you must be extremely careful and keep moving the rulers back and forth. On a construction site, determining elevations is usually the task of technicians; as for using a level, it’s not necessarily clear who is responsible for that. It’s important to note that the tilt of the vertical staff has a significant impact on the measurement results. Additionally, pinpointing the correct position for the vertical staff is difficult even for those who are not professionals. If you don’t give repeated instructions, it’s not unusual to see discrepancies of 3 to 5 millimeters. There is another saying that circulates on construction sites; although it’s not entirely accurate, it can be considered a useful tip for surveyors to protect themselves: “Keep the triangles small and the lines thick.” In other words, when marking elevations with red triangles, don’t make them too large, and use thicker ink lines when drawing the marks. Hehe, figure out what it means by yourself. As a site technician, it is essential to be proficient in the use of levels, theodolites, ink lines, and plumb bobs. As for material planning, whether the budget specialist has made suggestions or not, as a technician you must calculate everything yourself. You need to determine the actual amount of materials required, rather than relying on the amounts specified in the budget standards. These standards are established based on various types of projects, and the quantities indicated in some of them may not be suitable for actual construction; in other cases, they might even be insufficient. For example, when it comes to tiles and marble, the design already specifies the dimensions and specifications, so you can calculate the actual number of tiles needed, including those that need to be cut in half. If you put in the effort, you can determine the exact quantities required. This way, when you go to the site for inspections during construction, you will be confident and able to spot problems right away. Currently, the 03G101 atlas is generally used for steel bar design. Having just taken a course on reinforced concrete, you should be more familiar with it than others. When specifying the amount of steel bars required, it’s important to take into account the number of bar joints. When setting up a concrete mixer, cement is generally allocated based on the budget; once the concrete mix ratio is determined, the amount used per cubic meter is adjusted accordingly. Sand is usually planned at 0.5 cubic meters per cubic meter, while gravel can be planned at 1 cubic meter per cubic meter. Speaking of technical briefings, the common problem with them is that they involve too much copying from documents and standards, with little that can actually guide construction work. From my experience, when you’re not clear about the construction methods and procedures, it’s better to copy more of the regulatory requirements. Others might say that your instructions are a mere mechanical application of those rules and fail to provide guidance for actual construction, but it’s still better than having people say that you don’t understand the subject or that you use jargon. Another reason is that the technical instructions are to be included in the handover documents, so it is absolutely not allowed to include any statements that violate the standards. After all, there are things that can be done but not written down. If you want to improve, you should observe the workers’ operations more closely, identify what isn’t being done according to the instructions, and see how that affects the quality; be sure to write it down and make a summary of it. In some reputable organizations, the sampling of raw materials upon arrival for testing is carried out jointly by a sampling witness, a material handler, and the supervisor; as a technician, one should also participate in this process. What is learned in school, or what is memorized from standards and regulations, is not as effective as what is learned through actual experience. For example, when selecting specimens for testing the mechanical properties of rebar, it is not sufficient to simply take samples from the ends of the rebar – generally, about 1 meter needs to be cut off before sampling, in order to eliminate the effects of hot rolling during rebar production on those ends. It is important to note that the purpose of on-site sampling and retesting is to conduct random sampling so that each group of specimens truly represents the overall population. If the supply channels for steel materials are reliable and there is a long-term partnership with a high reputation, it is also possible to take all the steel specimens of that specification from a single rebar bar, as this avoids the need to create additional joints during the rebar preparation process, thereby preventing waste of material. But remember what the standard practices are; no matter how well you think you get along with the owner and supervisor, you must never tell the truth if you are not following the rules. Of course, for new technicians, it’s best to follow the standard procedures strictly. The first advantage is that it gives one a sense of peace of mind, and the second is that it creates a good impression of being conscientious in one’s work. When sampling cement, it is necessary to take a sample from each of any 10 bags in accordance with the specifications, mix them together, and then send the mixture for testing. The advantage is that it provides the laboratory with data as close as possible to real-world conditions, enabling the formulation sheets to be more cost-effective and scientifically sound. On-site quality inspections, checks on the dimensions and elevations of formwork, etc., may seem simple, but accumulating experience is also very important. By spending time on the site for an extended period, one can identify which areas are critical; it’s important to carry out preventive control in advance. It is something that project managers and operators dislike the most – having to use instruments to find faults after things have already happened. After working hard for half a day, when you present the test results to your supervisors and project manager, they often don’t show any kindness; they might respond politely with a grunt of acknowledgment, or more bluntly, they’ll shut you down by asking, \"So what were you doing all this time?\" ” Filling in the hidden documentation, including keeping records of daily construction activities, is part of your responsibilities as a skilled worker. Don’t tell others who should do certain tasks or claim that it’s not the technician’s job; instead, regard the need to record the progress made over the day, the operation of machinery, and staff assignments while others are resting or drinking as an opportunity to learn for free. See how others arrange things, think about how certain matters are handled; speak less and focus more on observing others’ skills in assigning tasks and their approaches to dealing with supervisors. One should aim to lay the foundation for working on projects independently. Complaining is of no use; your hard work and efforts will be noticed. Gaining the recognition of your supervisors and the respect of your colleagues is the first step to doing a good job as a technician. There’s a saying I often tell those below me: don’t rush to achieve results; just focus on doing your work. You must be involved in the review of the rebar cutting list. If it is the usual practice in your organization for the rebar foreman to handle such lists, you should obtain one copy to check on your own. The main thing to verify is whether the positions of the rebar joints are appropriate; arrange the rebars listed in the document in your mind and compare them with the design drawings to ensure nothing is missed. If something is not clear, just ask the relevant person – there’s nothing shameful about that. To do technical work well, one must first create a positive working environment for oneself. Get those around you to accept you; if necessary, you can resort to petty tactics. The stage of a junior technician is the phase of carrying out construction and laying the foundation. It is during this phase that practical experience is gained and accumulated on the construction site, as well as the basic framework of interpersonal relationships is established, including the formation of one’s own style of handling tasks and matters. Drinking is inevitable on construction sites; it is needed for internal communication, and also when meeting with client supervisors. If you can drink 500 grams, say that you will drink only 250 grams; if you cannot handle 250 grams, simply state that you don’t drink at all. Whether it’s your supervisors or colleagues, insisting that you won’t drink no matter what is the right approach. My experience is that drinking alcohol doesn’t solve any problems at all; on the contrary, it often leads to bad outcomes. Just think about it: not to mention saying things that are excessive when you’re drunk (which are actually nonsense), you turn red in the face, wave your hands around; even if what you say is correct, people will still assume it’s just what one says when drunk. Enough with the general talk; let’s now discuss some specific details on site. Industrial buildings generally feature a frame-type structure. For such buildings, it is important to keep the following in mind (I’m talking about general situations; if there are any mistakes, please feel free to point them out): 1. When constructing the cup-shaped foundations, consideration must be given to the prefabrication of the columns. 2. The side columns are not on the axis; they are offset by 500 units, so that the wind-resistant columns are not directly below the roof trusses. 3. Generally, three columns are prefabricated and stacked together, as this eliminates the need to use a base membrane; is it possible to use four columns instead? Is the amortization expense for the placenta in that case smaller? The answer is: if four are stacked together, the typical small dimension of precast columns is 400–500; so how tall will four stacked columns be? It’s almost 2 meters, which makes pouring concrete inconvenient; a scaffold needs to be set up. 4. Attention should be paid to the embedded components in columns. In general, the embedded components in factory building columns include those for inter-column supports, those on the keel surfaces, those for the connection plates of crane beams, and those for the walkway slabs of crane beams, among others. Precautions and key operating points for lifting precast columns: Column lifting is generally carried out by using a lifting point at one location; the rotation method is employed. Once the column is in position, it is lifted vertically. When the bottom of the column is about 200 mm above the top of the cup, the lifting arm is rotated to align with the top of the cup. The operator holds the column in place and aligns it with the cup’s opening, then slowly releases the rope. When the bottom of the column is approximately 3–5 cm away from the bottom of the cup, the lift is stopped. The column is aligned with the axis at the bottom, and 8 wedges are inserted – two on each side – after which it is gently tapped with a hammer. First, the center line of the smaller sides is adjusted, followed by the axis of the larger sides, until the column settles firmly at the bottom of the cup. Hard stones are used to secure the column’s base, with two points secured on each side to ensure accurate positioning. The column is then gently tapped again, and a theodolite is used to adjust its verticality on both the larger and smaller sides, with further tapping to ensure firm fixation. Once the plane position and verticality of the column have been adjusted, pour C25 fine-grained concrete promptly. Before pouring, remove any debris from the gaps and moisten them with water. If there are large voids at the bottom of the cup, first fill those voids with thin cement slurry; only after they are filled should the fine-grained concrete be poured. The grouting is carried out in two stages: in the first stage, the grout is poured up to the bottom of the wedge, and the area is compacted using rebar; once the concrete has reached 25% of its designed strength, the steel wedge is removed and then fine aggregate concrete is poured in to fill the space. Note: Do not touch the wedge during the first vibration of the concrete to avoid affecting the verticality of the column. The quality of column installation directly affects the connection of other components such as roof trusses; therefore, it is essential to properly align the columns. If adjusting their verticality affects their horizontal position, the \"reverse pushing method\" should be used. If a column is tilted to the left, it needs to be moved to the right. First, place a heavy hammer in the gap between the left-side cup and the column. If there are stones blocking the column base, those stones on the right side must be removed. Then, place a hard stone in the right-side cup and use a wedge to strike that stone, causing the column to rotate around its axis. To reduce the resistance from the strikes, the wedge on the back side can be slightly loosened, after which a smaller steel wedge can be used on the front side for striking, with the use of a theodolite for monitoring. For the frame structure of factory buildings, attention should be paid to the coordination of construction processes. The difficulty in constructing industrial buildings lies in the construction of the equipment foundations; due to the requirements for installing equipment, the relative dimensions and elevations must meet very strict standards. The general control principle is: the size of the protruding parts should be as small as possible, while the size of the recessed areas should be as large as possible; the elevation of flat surfaces, especially the elevation of the top of embedded components, should be as low as possible. Below is a technical briefing I wrote in 1999; it’s provided here for reference. Everything stated is the truth, and it was meant only for the work teams – the documents submitted for completion were compiled differently. Explanation of tasks: Fabrication and installation of \"H\"-shaped steel beams. 1. Mark out the shapes and cut the materials according to the 1∶1 scale shown in the drawings; straighten the profiles before and after cutting. If any issues are detected during lofting, contact the project department promptly to resolve them before proceeding with cutting. 2. The node size and weld size must meet the requirements of the drawings. 3. After rust removal and application of a coat of anti-rust paint to the metal components, assemble them. 4. When extending the connections of components (parts), the node connection method shall meet the requirements of the Construction Manual. 5. During the fabrication of the brackets (i.e., HJ-1 and 2) on the 26.0-meter platform of this project, each bracket is made up of two separate components; the connecting plates between the upper and lower chords are not welded (this is mainly to take into account the lifting capacity of the tower crane), and they are assembled together after being installed in place. 6. For each HJ-1 and HJ-2 unit, when it is turned over after being taken out of the mold (or lifted into place), two 100×100 wooden planks should be tied to its web members, and four lifting points must be ensured. 7. The sleepers and shaped steel used to construct the platform should be leveled and secured; the platform must have a ground wire, and it should be leveled again before each use. 8. Whether it is a bracket, column, or knee, the elevation line and center line for its installation must be marked at the installation location, and it is necessary to verify whether the elevation (center line) provided by the civil engineering team is correct. 9. The content of the commissioned processing is the \"electrolytic purification and recovery of flue gas\" for 11.2 M and 14.467 M, as well as the work related to the \"H\"-shaped steel beams of the roof trusses and the wall frame columns ； ““Ultra-concentrated phase transportation of alumina” 10.7 M steel platform steel beam (H500×20010×16). 10. In the diagram for “Electrolytic Flue Gas Purification and Recovery” SG0316-4T1-17, it is specified that the frame beams should be broken at a distance of one meter from the end. However, to facilitate lifting and installation on site when manufacturing the “H” beams, they are only broken at one end; during cutting, they are still treated as single pieces without any breaks, with welding being avoided only at the points where a break is required. This also facilitates transportation in the future ； The rest shall be constructed according to the drawings. 11. Since the position and length of the embedded bolts in the civil engineering work may deviate from the design specifications, the base of each column must be cut to size and drilled according to the actual conditions on site. 12. The “H”-shaped steel for the columns has been processed in the factory; the angle irons and connection plates on it have not yet been welded – these must be welded on-site. When welding these components, it is necessary to adjust them according to the elevation of each foundation. If the foundation is higher than designed, the “H”-shaped steel should be cut; if it is lower than designed, shims should be added under the base plate. 13. Before lifting the column, the longitudinal and transverse center axes of the foundation should be marked on it; the center lines on all four sides of the column should also be marked and numbered. During lifting, the column should be positioned according to these marks. Meanwhile, two theodolites should be used to check the verticality of the foundation, and shims and wind ropes should be employed to align it properly. 14. Before installing the frame beams, install the inter-column bracing first, and then install the frame beams in sequence from bottom to top. 15. The cutting of secondary beams should take into account the actual dimensions on site; first, mark their installation locations. 16. After the framework and platform are installed, the wall frames should be welded in place; the spring plates at the joints between the wall frames and the roof beams, as well as the reinforcing plates on the beams at their bases, must be installed according to the specifications. 17. The key to the installation of this project is that careful rechecking and attention must be paid to aligning the column centerline and ensuring its verticality. This post was last edited by macgrady on 2009-3-15 09:56]