Three training reports on engineering survey

# Internship Report # Introduction Through the engineering survey training, I really learned a lot of real things, such as being more proficient in operating surveying instruments and leveling, and learning things that I can't do in class, such as drawing digital topographic maps and measuring damaged parts, which greatly improved my hands-on and brain-thinking ability and expanded my ability to communicate and cooperate with my classmates. Three engineering investigation training reports compiled for you, I hope to help you!

Tisch

Engineering survey practice, as a compulsory practice course for civil engineering majors, is of great importance to students majoring in construction engineering. Scientific measurement is not only to acquire the theoretical knowledge of books, but also to cultivate our hands-on operation ability and profound understanding and summary of the theoretical knowledge of textbooks, so as to realize the guiding significance of the principle of "from control to fragmentation, from whole to part, step by step inspection" in engineering measurement. Mastering this skill is of great help to the future construction site. After all, the opportunities given to students by domestic universities are far from enough to meet their needs. Therefore, we must create knowledge benefits in limited opportunities. Of course, we can also improve our thinking structure and cultivate the spirit of cooperation and leadership by measuring the internship platform.

First, the purpose of internship

1, the placement, leveling and aiming of contact level can measure the height difference between any two points, master the operation, use and maintenance methods of level, and be familiar with the layout form of level route.

2, master the theodolite, leveling, aiming, master the horizontal angle and vertical angle measurement, master the operation and maintenance methods of theodolite.

3. Through practice, master the theoretical knowledge and practical skills in class.

4, master the method of steel rule distance.

5, the use of theodolite and level mapping topographic map.

6, master the layout and calculation method of small area plane control and elevation control, and master the surveying and mapping method of large-scale topographic map.

7. Improve hands-on ability and comprehensive ability to analyze and solve problems, and lay a solid foundation for future work.

8. Cultivate the spirit of loving the profession, loving the collective and working hard, and gradually form a United, cooperative, rigorous and pragmatic work style and an attitude of working hard.

Second, practice equipment

DS3 micro-tilt level, DJ6 optical theodolite, spirit level, 30m steel ruler, benchmark, drawing paper, pencil, eraser, etc.

Third, the content and requirements of the internship

1, plane control measurement. Generally speaking, closed traverse is used for control measurement of root plane. What needs to be done is: reconnaissance and point selection: according to the purpose of surveying and mapping and the topography of the survey area, the layout form of traverse is drawn up, the traverse points are selected on site and signs are set up. Observation of horizontal angle: the traverse angle is measured twice with theodolite. Side length measurement: the side length of the conductor can be measured by theodolite sight distance method, and it needs to be measured back and forth. Traverse result calculation: firstly, check the field survey data, and carry out closed difference adjustment when the observation results are qualified, and then calculate the coordinates of control points from the initial data.

2, elevation control survey. Field survey: According to the requirements of fourth-class leveling, DS3 level is adopted for field survey. Indoor calculation: after the field observation results meet the requirements, the adjustment calculation of closed leveling route results is carried out according to the elevation of known points and observation elevation, and the elevation of each leveling point is calculated.

3. Topographic map drawing. Preparation of drawings: first draw the grid by diagonal method, and then control the display points. Check after spreading points, measure the distance between adjacent control points on the map with a scale, and compare with the measured distance. Crushing measurement: The method of theodolite combined with protractor is adopted for crushing measurement. According to the principle of sight distance measurement, the horizontal distance and height difference between the vertical ruler point and the station are measured and calculated, and the vertical ruler point is drawn on the map according to the polar coordinate method and the elevation is marked.

Fourth, internship experience

Engineering survey practice is a compulsory course for all students majoring in civil engineering. Although some measurements have been made in the engineering survey class, those experiments are mainly aimed at a certain piece of measurement. We always feel that we lack some practical ability and the ability to combine theoretical knowledge with practical operation, so I personally think it is necessary to do this practice well, not only because of a course, but more importantly, to provide some measurement experience for our future work.

Through this internship, we consolidated, expanded and deepened the theoretical knowledge learned in class, mastered the basic operation of theodolite, reached a certain level of proficiency, and also had the opportunity to learn the method of topographic map drawing. In addition to the preliminary experience and basic skills in surveying practical work, we also focused on cultivating the ability to work independently, the ability to find and solve problems in the surveying field, and further mastered the skills of using surveying instruments, improved the data calculation ability and sensitivity to data, and had a comprehensive and systematic understanding of the whole process of surveying and mapping large-scale topographic maps in small areas.

Measurement practice is the work of a team. There are 15 members in our group, and everyone's work tasks and strengths are different. Only cooperation can play a higher role. My main task is to measure the horizontal distance with instruments. This measurement is mainly to complete the selection of control points. Due to the different topography of Building No.2 xx, the control points should be selected with good mutual perspective, flat terrain and uniform distribution, so they have been preserved and the angles and distances have been measured. After our joint discussion, we finally decided. Personally, I think all the control points are good except for a few control points. After all, there are many trees in Building xx No.2, and there are steps with large height difference, so it is impossible to consider all the points in the survey process. Due to the high precision of control measurement, ignorance of operation and instruments, and discussion of some methods, the measurement of control points took a long time to complete. Finally, the measurement of control points is completed.

Because there are few opportunities to exercise at ordinary times, I cherish this intern. Each member of this group made independent observation, recorded each station and calculated theodolite measurement on site. Find problems and solve them in time. If you don't check the previous step, you will never make the next measurement, so you can check it step by step in the office and make accurate calculations when you come back, because doing so can not only prevent the accumulation of errors, but also find errors in time and improve the measurement. Even if we re-test, we are rigorous, rework if there are mistakes, and never be careless. Until the measurement requirements are met. We know that in engineering, what we need is carefulness, patience, perseverance and rigorous attitude. Only in this way will you be handy when you go to work in the future and take fewer detours.

extreme

First, the internship content

1, leveling

According to the elevation of known leveling points, measure the elevation of other leveling points.

2, traverse measurement

The coordinates of each traverse point are obtained by measuring the angle and distance.

3, step measurement

According to the control points, determine the plane position and elevation of the broken step point.

4。 Painting.

Second, the internship steps

1, leveling

(1) leveling principle

Leveling is to directly measure the height difference between two points on the ground by using the horizontal line of sight provided by the level, and then calculate the elevation of the unknown point according to the known point elevation and the measured height difference.

Let the leveling direction be from A to B, where A is called the back viewpoint and A is the back reading; B is called forward view, and B is called forward reading. If the elevation of point A is known, the elevation of point B is HB=HA+hab, HA+a=HB+b, and HA = HB+A-B .. The elevation of point B can also be calculated by the sight elevation of this elevation, that is, Hi=HA+a, HB = Hi-B. ..

(2) Site leveling measurement

Leveling point: A point where elevation is measured by leveling.

When the leveling point of the predicted elevation is far away from the known leveling point or the height difference is too large, it is impossible to measure the height difference by placing the instrument 9 between the two points. At this time, it is necessary to set up multiple stations for composite leveling. The sum of the height difference of each station can get the height difference between the predicted leveling point and the known leveling point, so as to get its elevation.

(3) Leveling inspection

Calculation check: the sum of closed conductor height difference is equal to the sum of height difference at the turning point, which is equal to the sum of backward reading MINUS the sum of forward reading, so this formula can be used to check the correctness of calculation.

Station inspection: check every reading of each station, and check by changing the instrument and method. The method of changing the instrument requires that the changed height should be greater than 10cm, and the difference between the two heights should not exceed the specified allowable value, that is, 6 mm

Results detection of closed leveling route: In theory, the sum of the height differences of each measuring section should be equal to zero, but in practice it will not. There is a height difference, which cannot be greater than your allowable value, that is, if the height difference exceeds this range, it means that there is an error in your grades and you have to return to work.

(4) Calculation of leveling in the office

Check the leveling manual; Fill in the known and observed data; Calculate the closing difference of height difference and its tolerance.

2, traverse measurement

Fill in the checked field observation data and initial data in the "Closed Traverse Coordinate Calculation Table", and mark the initial data with a single line.

Calculation and adjustment of (1) angle closure difference

The theoretical value of calculating the sum of internal angles of N- sided closed conductors by angle closure difference is: where N-number of sides or rotation angles of conductors. Because the observed horizontal angle inevitably contains errors, the sum of the measured internal angles is not equal to the theoretical value. The difference between them is called angular closure difference, which is expressed by fβ, that is, the allowable value of angular closure difference is calculated. The magnitude of angle closure difference reflects the quality of horizontal angle observation. Allowable value fβp of wire angle closure difference at all levels, in which the calculation formula of allowable value fβp of wire angle closure difference at the root of the figure is: If >；; , indicating that the measured horizontal angle does not meet the requirements, and the horizontal angle should be re-checked or re-measured. If ≤, it means that the measured horizontal angle meets the requirements, and the measured horizontal angle can be adjusted.

Calculate the correction number of horizontal angle. If the angle closure difference does not exceed the allowable value of the angle closure difference, the opposite sign of the angle closure difference is evenly distributed on all the observed horizontal angles, that is, each horizontal angle is added with the same correction number. The calculation formula of vβis: calculation check: the sum of the horizontal angle corrections should be equal to the sign of the angle closure difference, that is, the corrected horizontal angle β i is changed to equal to the measured horizontal angle plus calculation check: the sum of the corrected internal angles of the closed conductor should be (n).

(2) calculating the coordinate azimuth of each side

According to the known coordinate azimuth of the starting edge and the corrected horizontal angle, calculate the coordinate azimuth of other traverse edges according to formulas (4- 18) and (4- 19). In this example, observe the left corner, calculate the coordinate azimuth of each side of the conductor according to the formula, and fill in the table. Calculation check: finally calculate the coordinate azimuth of the starting edge, which should be equal to the original known coordinate azimuth of the starting edge, otherwise the calculation should be checked again.

(3) Calculation of coordinate increment and adjustment of closing difference.

Calculate the coordinate increment. According to the calculated coordinate azimuth of each side of the conductor and the length of the corresponding side, the coordinate increment of each side is calculated. In fact, the calculated coordinate incremental closure difference is not equal to zero due to the residual error after the adjustment of the wire side length measurement error and the angle closure difference, thus resulting in the vertical coordinate incremental closure difference Wx and the horizontal coordinate incremental closure difference Wy, that is, the total length closure difference WD and the total length relative closure difference WK of the wire are calculated. WD= relative closing difference of total conductor length WK. The WKP of the root conductor is 1/2000. If WK & gtWKP means that the result is unqualified, the indoor calculation and field work of the commander should be checked at this time, and retest is needed. If WK≤WKP, the measurement results meet the accuracy requirements and can be adjusted.

Adjust the closing difference of coordinate increment. The principle of adjustment is to reverse the symbols of Wx and Wy and assign them to the vertical and horizontal increments corresponding to each side according to the principle of being proportional to the length of the side. Vxi and vyi respectively represent the vertical and horizontal increment correction numbers of the ith edge, that is, the calculated value of the coordinate increment of each edge after calculation is added with the corresponding correction number to obtain the corrected coordinate increment of each edge.

3, step measurement

(1) Selection of Step Points

Fault step points are the characteristics of ground features and landforms. For ground objects, the step-breaking point should be selected at the direction change of the contour line of ground objects, and the shape of ground objects similar to the site can be obtained by connecting these feature points. For geomorphology, the fault step point should be selected on the geological line that best reflects the geomorphological characteristics, such as ridge line and valley line.

(2) Theodolite mapping method

During observation, the theodolite is placed on the station and the drawing board is placed next to the station. Use theodolite to measure the included angle between the direction of the step breaking point and the known direction, the distance from the station to the step breaking point and the elevation of the step breaking point. Then, according to these data and the proportional position of the fault step point, draw it on the map, mark its elevation on the right side of the point, and then draw the terrain against the field.

4. draw pictures.

Third, the causes of errors caused by practice and solutions

1. There are three main sources of various measurement errors:

(1) instrument error (determined by the instrument itself and an objective error source).

(2) Observation error (due to the technical level of personnel, it is a subjective error source).

(3) External influence error (it is influenced by external factors, such as temperature and atmospheric refraction, which changes all the time and is difficult to control, and belongs to a variable error source).

2. Methods to reduce measurement error

(1) Appropriate high-precision instruments should be selected for instrument selection.

(2) Improve the measurement level and reduce the error level.

(3) Processing data by various mathematical methods to reduce errors, such as temperature correction, ruler length correction, multiple average measurements, etc.

Fourth, internship experience

Compared with the previous teaching practice, the real engineering (internship) can obviously better understand the knowledge learned. That's true. Through this internship, I really realized the importance of integrating theory with practice.

Measurement is first and foremost an accurate job. By studying surveying in class as a student, I have formed the basic and theoretical outline of surveying in my mind. The purpose of practice is to link these theories with practical engineering, which is the characteristic of engineering. Surveying is a science that studies the shape and size of the earth and the points on the ground. In essence, the main task of measurement is to determine the position of the ground target in three-dimensional space and its change with time. In the information society, the role of measurement is becoming more and more important. As the foundation of GIS, the survey results provide the most basic spatial position information. To build information expressway, basic geographic information system and various thematic and professional geographic information systems, it is urgent to establish a unified standard survey database and survey results information system. Therefore, surveying has become the most reliable and accurate means to acquire and update basic geographic information.

Through this internship, I have exercised a lot of basic abilities in surveying and mapping. First of all, I am familiar with the purpose of the instrument, proficient in various ways of using the instrument, and mastered the inspection and calibration methods of the instrument. Secondly, in the process of checking and correcting the data, I learned the sources of various measurement errors, and how to avoid the errors of measurement results and the methods to minimize the measurement errors.

In addition to being familiar with the use of instruments, understanding the sources of errors and measures to reduce errors, we should also master a set of scientific measurement methods, and follow certain measurement principles in the measurement, such as "from the whole to the part", "controlling the part first" and "from high to low" to achieve "step by step inspection". Doing so can not only prevent the accumulation of errors and find them in time, but also improve the efficiency of measurement.

Through practice, I really learned a lot of real things, such as being more proficient in the operation of measuring instruments and leveling, and learning things that I can't do in class, such as drawing digital topographic maps and measuring damaged parts, which greatly improved my hands-on ability and brain ability, and also expanded my communication and cooperation ability with my classmates.

At the same time, in this internship, I once again realized the importance of internship team spirit: one carelessness of everyone may directly affect the progress of the project and even bring irreparable losses for a lifetime. It is far from enough for a measurement practice to be completely completed. Only the cooperation and unity of the group can make the exercise complete quickly and efficiently. This investigation practice has cultivated our team's ability of division of labor and cooperation, and enhanced the feelings between students. And these are all measuring the harvest.

Generally speaking, this internship made me realize the hardships in the field, the patience in the field, the care in my work, and even the awe of the surveyors in the early days of the founding of the People's Republic of China. I have exercised my practical ability and made myself more confident and brave in the face of future choices.

Tisso

The internship is organized by the college, led by the teacher, and students discuss and communicate independently, completing the tasks assigned regularly. Weather is an important factor. During this period, we should seriously deal with the changes of climatic conditions that are often encountered in these field surveys. The weekly task is arranged on Friday or weekend before last week, and the data is checked on weekends, so that each of our students can better enrich their theoretical knowledge and check the problems in the measurement process. Although these three weeks of hard and beneficial engineering survey practice are over, these three weeks are really a test for us, during which there are pains, tiredness, sweetness and joy; During this period, there are difficulties and obstacles, but also great gains. With the improvement of practical ability, there are more theoretical knowledge. It is no exaggeration to describe pleasure in suffering. In any case, internship is a happy job, at least bid farewell to the strong radiation of dormitory display screen and get close to nature.

The tasks in the first week are elevation survey and traverse survey. Elevation measurement is simple and easy. We used the coordinate orientation to determine the orientation, and we finished it quickly and smoothly. Because of its high precision, traverse survey needs complex data processing, but these do not affect the progress. Don't forget the textbook knowledge at any time. You can refer to the textbook, ask the teacher and discuss with your classmates when you encounter problems. In order to accomplish the task effectively, a series of actions are necessary. In the process of completion, I learned the knowledge of classroom learning. In the early stage of this task, I carried out elevation survey with a team member, cooperated with other team members to participate in traverse survey, and calculated all kinds of data in the whole process, which benefited a lot.

The second week's task is local topographic mapping. The surveying and mapping of topographic map requires higher ruler, and the quality of ruler is directly related to the quality and progress of the results. I volunteered to shoulder this burden, and I was also responsible for the operation of some parts together. The erection of the instrument is also a hard work, and it must be down-to-earth to achieve the ultimate blending. When operating instruments, leveling observation records (notes and computer storage) run through the whole process of measurement, and attention must be paid to details. This task needs the active cooperation of everyone in our group to complete smoothly and quickly, and the active cooperation of team members can complete the task quickly. In this task, I worked as a coordinator, ruler, inspector and draftsman, that is, I participated in every job. Efforts in measurement are inevitable, but not enough to hinder the pace of measurement. Last week's task was to put control points. Although this week's accuracy requirements are relatively low, due to the large amount of tasks, the work cannot be sloppy. After the completion, the perceptual knowledge of topographic mapping has been greatly improved, and the experience of selecting traverse points has also been greatly improved.

The most important thing for us to carry out joint measurement is to coordinate with each other and embody the spirit of team cooperation, which is also the premise of completing this measurement task with high quality and efficiency. Similarly, the team spirit among team members is also an important part that cannot be ignored. In this measurement practice, we have embodied its significance. Measurement is a demanding job. It is necessary to complete the measurement of the distance, elevation and height difference of each measurement section according to the measurement requirements, and accurately measure and describe the topography, features and landforms of each measurement area, including a large number of indoor calculations and proofreading, processing and rechecking of various data. At the same time, all the measuring points are carried out on the grid according to a certain proportion, and these tasks are almost carried out at the same time. This requires all our team members Qi Xin to work together, unite as one, coordinate all the work, and arrange the work of all team members reasonably, so that every team member can learn and be familiar with the use of instruments and office calculations as much as possible. This is also the primary purpose of our internship, and it is also a test and supplement to the previous study. In order to consolidate our study, we should check and fill in the gaps in this internship. Each team member's foundation and ability are different, so when arranging the measurement task, we can divide the work according to everyone's actual situation, which can also improve the measurement efficiency.

Surveying and mapping is also a pragmatic and realistic work, and must not be sloppy. In measurement practice, it is also very important to keep the data original. In order to ensure the correctness and effectiveness of the calculation, we must proofread the data of each measuring point repeatedly. Inevitably, we will make some mistakes in the measurement, such as inaccurate reading, reading when the leveling rod or flower pole is not vertical, and the reading interval is too long. , will cause some errors. Therefore, indoor calculation and measurement should be carried out at the same time in the measurement, so as to find and correct errors in time, avoid many unnecessary troubles, save time and improve work efficiency. Because this is a historic work, a lot of data may be used in the future, so we should try our best to improve the validity of all data, and keeping the original data is also conducive to future verification, which also reflects the spirit of seeking truth and being pragmatic, not only in this experiment, but also in our future work and life.

In the third week, the task is to investigate the route. Our team did a field survey first, and the route we chose took into account both economy and gold content. After the line selection is completed, everyone will calculate the inner page. The calculation of the inner page is large, and we will start lofting after calculation and careful verification. The field work was completed in two days, and piling was a hard job. For the sake of pedestrians, it took a lot of effort to drive the pile in. Longitudinal survey and horizontal survey on the last day. For the measurement of these two external pages, we explored and verified the operation and inspection steps of the instrument, then started the measurement, and finally processed the data drawing. In this task, I participated actively and comprehensively, and got to know and deepen all aspects of the theory and practice of vertical and horizontal sections.

The completion of all the tasks in these three weeks has devoted a lot of effort to our group. It is far from enough to do a complete survey practice by one person's strength and conception. Only the cooperation and unity of the group can make the exercise complete quickly and efficiently. Cooperation problems often occur during the internship, but we have the same goal, "faster and stronger", so we finally stood on a front to break through the siege. Therefore, as long as we cooperate sincerely, communicate with each other and understand each other, all problems are not problems. Sometimes the test comes back very late, so I can't catch up with eating in the canteen, so I can only eat instant noodles. It is very tiring to measure the outer pages during the day, and come back to process the data at night. There is sweetness in fatigue and joy in bitterness. Every one of us is full of passion every day and has achieved fruitful results in completing the task.

I deeply realized that through this practical measurement practice, I learned a lot of real things, such as operating experimental instruments more skillfully, learning the measurement of broken parts, traverse measurement and topographic map drawing, which greatly improved my hands-on ability and brain ability, and also expanded my communication and cooperation ability with my classmates.

This internship is also an opportunity to cultivate our independent thinking and working ability. In the process of measurement, we should all think about how to set up points, how to measure, what data to measure, how to ensure the validity of the measured data, and then discuss and solve them together. None of us have rich experience or talent in surveying and mapping. This is to stimulate our personal subjective initiative, give play to our personal intelligence and give ourselves a chance to play.

For more than three weeks, we have been sticking to our "position", observing, recording, calculating and tracing our own division of labor and cooperation, and striving to complete the task better and faster. In the whole measurement process, we encountered many problems and difficulties, and made many mistakes, which had a certain impact on the whole measurement progress. We also learned a lot from it.

In this measurement practice, due to personal factors, it has brought a lot of troubles to the measurement progress, such as carelessness and inattention to copying data, which led to problems in calculation; There are also calculation errors that will bring a lot of inconvenience to the subsequent surveying and mapping work. These mistakes that should not have happened are all caused by personal carelessness and inattention. We should correct our work attitude and do every job well in the future. At work, we should keep calm, so as to make fewer mistakes and improve work efficiency. This is also a condition for cultivating independent thinking. As long as this state is maintained, I believe many problems can be solved.

In a word, this measurement practice has given me a deep understanding, which not only provides me with a platform, but also improves my ability in all aspects, especially from the point of view of control to fragmentation, which is enough to promote various scientific fields, such as Mr. Qian Xuesen's system science. It not only emphasizes the importance of these structural frameworks, but also involves the habit of thinking, from point to surface, from line to surface, and then to body. Grasping key factors is also an optimized way of thinking. I benefited a lot from the internship, which improved my teamwork ability, collective sense of honor, hard-working ability, paid attention to taking care of public property and taking good care of instruments. All these have increased my practical experience, laid the foundation and achieved the expected purpose. Although I may not be directly engaged in surveying in my future work, this knowledge and experience will serve my future career and strive to become an outstanding talent in the field of road and bridge engineering.

Measurement practice is neither too long nor too short, and it takes some efforts to successfully complete the task. After all, we are "newborn calves" and there will always be some curiosity. However, in this internship, we also gave full play to our individual initiative and team spirit, and were able to complete the tasks assigned by our teachers. Although there are still many shortcomings, what we know and learn is only the tip of the iceberg in civil engineering survey, but we will not be proud, and we will continue to work hard in the future. It can be said that this internship is a major review since the whole semester of our undergraduate course, but we all know that this measurement task is not light and the responsibility is heavy, and no one dares to take it lightly.