Summary of the work of bridge construction technicians

I have been working at xxx company since July XX, and it has been almost a year. I remember that when I first arrived at the company, the company provided us with a one-week short-term training, which enabled us to have a deeper understanding of all aspects of the company's development, and at the same time, I realized that I had a shoulder in my thoughts and work. Heavier responsibilities and obligations. Soon we went to work and went to the company's assigned projects. I was lucky enough to come to the xx cross-sea bridge project that our bureau called the first sea bridge construction. In the past year, I worked as a surveyor and a field technician in two different positions. I did my due diligence to complete my job. The results were small and I felt a lot of emotion. Below I will make a brief review and summary of my work in the past year.

During the year of working at xx Bridge, I have always insisted on personal cultivation and made myself more mature and stable in my mind. As a member of the Communist Youth League, I have always strictly adhered to the standards of party members, adhered to the four basic principles of the party, loved the transportation and civil engineering undertakings, and did not talk about any conditions for work. I just did my best to do my job better. At the same time, I work together with my colleagues at work and live in harmony with each other. I think because of this, I was fortunate enough to be a member of the party's active party in May XX.

In terms of work, the position that the project department gave me at the beginning was a surveyor. The construction of the sea bridge required very strict measurement work, and the value of the xx bridge entered in July. Many jobs are still in the preparation stage, so The retesting work of the previous measurement is quite frequent, and there are many items to be measured, such as cross-sea standard, second-class level, control point encryption, red line stakeout and other construction stakeout. Let's say that this cross-sea quasi-measurement, in order to improve the accuracy of the retest data, improve the accuracy of the alignment, using two geodetic quadrilateral mesh forms to form a level closure with external inspection conditions based on cross-sea survey lines. Ring; through indirect measurement of instrument height, indirect calculation of height difference, indirect two-difference correction method, accurate data of 800 meters long-distance seawater quasi-measurement is obtained. In addition, in this measurement process, in order to minimize the adverse effects caused by atmospheric refraction, we have chosen to measure in the evening of good weather, which makes the collection of our data more feasible. In the retesting of the wire point, in order to reduce the error and improve the precision, we also use the white ruler to measure with the second-class electronic level, so that the data record is also automatically recorded by the instrument, and then the data is processed by a special professional software, and the data is feasible at a glance. It effectively reduces the unnecessary errors caused by artificial records and calculations. This greatly reduces the single-person measurement in the past, and strongly advocates the combination of science and technology and measurement work to achieve good results with half the effort. In view of the high requirements of the construction quality of the bridge, we not only use advanced instruments in the input of measuring equipment, but also the implementation of high standards and latest specifications in the processing of internal data. The measurement schemes and processes are required to achieve excellence, which makes me more comprehensive. And deeper understanding of the measurement work, but also give them more opportunities to access the instrument. This is a great learning opportunity for me who just came out to work. Through these, I deeply realized that measurement is a practical, professional, and highly demanding job. Although I don’t understand a lot of things, it has increased my interest in this work and gave me a lot of The motivation to learn has increased my enthusiasm in the work of intense fatigue.

In the past six months as a field technician, the main tasks have been the construction of the trestle and drilling platform, the decentralization of the steel casing and the pile foundation construction. Here we focus on the construction of deep and long pile foundations at sea. In the pile foundation construction of this project, there is a 23# transition pier and 24#, 25# two main piers for the offshore pile foundation, and the construction of the 23# and 24# two pier pile foundations. . The number of pile foundations is large, the pile length is large and the diameter is large, the pile quality is high, the construction period is tight, the geological conditions are complex, the cover layer is thick, the strong weathered layer and the weak weathered layer are thick, and the micro-weathered granite layer at the bottom of the pile is uniaxially pressed. High strength and other characteristics. Therefore, we made the following targeted pile foundation construction with reference to external data such as geological histograms:

Controlling mud indicators is key. The role of mud, in different geology, plays a different role. The scheme adopted for the 24# main pier is to continuously measure the upper sediment layer by using the method of filling and grouting and continuously circulating the slurry; the role of the mud in this stage is to serve as the carrier of the scum and to continuously protect the wall of the hole. Prevent collapse and perforation. For the later strong weathering and mid-weathering, the hammering and crushing slag is used to discharge the slag, that is, the impact positive circulation construction; the mud at this stage is mainly used for the scum carrier and the balance of internal and external pressure to prevent collapse and perforation. Mud needs to play a corresponding role, and can not be separated from two mud indicators: mud weight, colloid rate. If the specific gravity of the mud is too large, after more than 1.6, it will seriously affect the wire rope due to the stretching and rotation, and form the plum pile; it will also seriously reduce the drop kinetic energy of the hammer due to the excessive resistance formed during the falling weight, and increase the motor when lifting the hammer. Energy consumption, lowering the performance of beatings, resulting in increased power consumption, while the footage is smaller. The difference between the height of the mud surface and the height of the sea level is the main source of pressure difference between the inside and the outside. When the pressure difference is too large, there is a problem of internal and external perforation. In the steel casing area, since the steel casing of 2 cm 6 is used, there is no problem of perforation, mainly below the steel casing area. According to the geological histogram provided by the geological drilling construction, there is a certain thickness of sediment and soil layer below the steel casing, and occasionally there are residual soil layers and strong weathering and medium differentiation, although the underground water system is not very developed, there is no Large-scale groundwater is found, but in sediment-bearing soils and disfigured soil layers, and even in highly weathered layers, if the pressure difference is large due to internal and external pressure, the formation of perforations will increase the risk of collapse and the formation of cracks in the perforated position of the pile foundation after perfusion. Face, forming a b-type pile. In summary, the mud effect we use is nothing more than physical and mechanical effects.

Since these pile foundations are all rock-socketed piles, the thickness of the sediment at the bottom of the hole and the stability of the hole wall are highly demanded, so the quality of the clear hole directly affects the quality of the pile. In order to ensure that the mud index reaches the relative density of 1.03 ~ 1.10, the viscosity of 17 ~ 20s, the sand content is ≤ 0.5%, we use the pumping reverse circulation clearing hole, using air compressor air pipe to blow air into the air duct to form the pressure difference, With the black cyclone mud separator, the sediment in the upper mud is separated. At the same time, we must pay attention to the height of the water head in the hole to ensure that the height difference with the sea water does not cause collapse or perforation. Compared with the positive circulation, this clearing scheme has several advantages: the clearing speed and the pile forming efficiency are greatly improved; the hole wall is stable and the hole forming quality is good; the concrete pouring quality is effectively guaranteed; and the single pile bearing capacity is improved, Reduce the construction cost; adaptability, especially suitable for such deep sea pile construction.

Concrete infusion is an important part of the whole pile foundation construction. We use c35 underwater marine concrete according to the design, the slump is 200±20mm, the initial setting time is not less than 20 hours, and the single vertical pipe is used for pouring. The diameter is ф300mm. Before the infusion, we budget the first amount of concrete and the theoretical total amount to determine the suspended height of the bottom of the hole before the filling. At the time of perfusion, we mainly grasp the workability and slump of the concrete itself. It is related to the smooth infusion of concrete through the catheter. The workability refers to the uniform mixing of various raw materials of the concrete and the uniformity of the package between the mud and the bone; the coagulation with poor workability.

The soil is prone to segregation and even bleeding, causing the concentration of aggregates to cause easy blockage and the strength of the concrete in the later stage, and the strength of each part is different. Slump, in fact, also refers to the fluidity of concrete, according to the design of the underwater concrete slump is 180 ~ 220mm, too small flowability is easy to block the pipe during the infusion process, resulting in broken piles, too large and easy to cause in the process of cutting Falling off, affecting late strength. I think that we must do a good job of the pile foundation at sea. These three points are the most important ones. They are the key indicators that I will focus on in the construction of pile foundations in the future.

In the days when we participated in the work, our project department has been strongly supported and paid attention from all walks of life, and received many praises. At the end of XX, we won many honors such as “Chuzhou Youth Civilization” and “Advanced Collective”. In order to do my part, I will give the project department “adding bricks and tiles”. During the construction process, I put forward the following requirements for myself: 1. Diligent business, improve personal business ability, diligently read drawings, diligently learn, complicated things on site, and master more Countermeasures as their own backup force; 2. Ken service, the scene is a coordinated process, is a platform for multi-party help, focus on service; 3. Peace of mind, from the start of the project, we build the trestle, lay the platform, decentralize Steel casings, perfusion bored piles, our work is in a dynamic, there are many things that we have not experienced, when we encounter things, our mentality must be flat, and we want to solve the problem instead of complaining; 4. will communicate After a plan is determined, the site is the most direct platform to control the quality, schedule and cost of the project. We must learn to listen and suggest, instead of obeying and obeying, communicating with the construction team and listening to it within the appropriate scope. Ways, suggestions for good countermeasures; 5. Dare to manage, the site is the most contact with the construction team, they have problems we must be good at discovering and solving, to ensure the work There is no hidden danger in the quality of the process, the construction period is not lagging, and the cost is feasible. 6. Good unity, it is not something that can only be done by one person's strength. In many cases, it is necessary to know how to cooperate and unite. This may be better. 7. Good summary, what is happening The problem and the work method should be summed up in a systematic way so that they can be solved in the future when they encounter similar problems, and even better can be handled.

The above is a summary of my project, post technology, and ideological consciousness during my one-year work. In the future work, I will work harder to learn professional skills, improve my personal business level, improve my own quality, overcome my own shortcomings, standardize engineering construction management, and strive to do better in all aspects to serve the company.