第一节 施工测量概述
　　 一、施工测量的任务和原则
　　 一般的大中型土木工程在开工建设之前，都要在地形图上进行设计，所设计的内容经过讨论、修改、审核通过以后就可在施工场地进行放样，只有通过准确地放样才能开展施工。
　　 上程建设在施丁阶段所进行的各种测量工作，称为施工测量。施工测量的基本任务是用测量仪器、根据测量的基本原理和方法，把图纸上设计的建(构)筑物的平面位置和高程，按照设计要求，以一定的精度测设到地面上，标上相应标志作为施工的依据；并在施工过程中进行一系列的测量工作，以衔接和指导各工序间的施工，保证工程按设计要求进行施工建设。
　　 施上现场有各种建(构)筑物，且—般分布较广，往往又不是同时开工兴建。为了保证各个建(构)筑物的平面位置和高程都符合设计要求，互相连成统一的整体，施工测量和地形图测绘一样，要遵循“从整体到局部，先控制后细部”的原则，任何施工测量工作都要先在施工场地上布设统一的平面控制网，然后再以此为基础测设各个建(构)筑物的位置。
　　 除应遵循上述原则外，施工测量中的检校工作也很重要，必须采取各种不同的方法随时对外业和内业工作进行检校，以保证施工质量。
　　 二、施工测量的内容
　　 施工测量贯穿于整个施工过程中，内容包括：施工控制网的建立；在施工过程中，随时给出建(构)筑物的施工方向、高程和平面位置；检查建(构)筑物的施下是否符合要求，并随时给予纠正和修改；在建筑设备和工业设备安装阶段还要根据工艺和设计要求给出安装的空间位置和方向；工程竣工后，为了便于管理、维修和扩建而进行的竣丁测量。由此可见，施工测量自始至终贯穿于施工的全过程。
　　 三、施工测量的特点
　　 与地形测图相比，施工测量具有下列特点：
　　 (1)地形测图是将地面上的地物、地貌测绘到图纸上，即从地表到图纸；而施工测量是将图纸上设计的建(构)筑物测设到相应的地面上，是从图纸到地表。
　　 (2)地形图的精度与比例尺大小打关，比例尺越大，测图的精度越高；而施工测量的精度取决于工程建设的性质，即取决于建(构)筑物的大小、所用材料、用途及建(构)筑物的定位精度。总之，放样的精度应根据设计要求来确定，精度要求过高，将导致人力、财力、物力及时间浪费，过低的测设精度则会影响施工质量，不符合要求，造成返工浪赞，甚至导致工程事故。
　　 (3)施工测量贯穿于施工的全过程，工作量大，作业频繁，上作过程中任何一点差错，都将影响施工的进度和质量，所以施工测量人员必须具有高度的责任心。
　　 (4)施千现场上种多，有大量上方填挖，地面变化大，又有各种施工机械振动影响．地面、地下和高空三方面同时作业，环境复杂，对测量工作影响较大。要求各种测量标志必须埋设稳固，且进行妥善保护，经常检查，若有损坏应及时恢复。
　　 四、施工测量的工作要求
　　 1．紧密结合施工进程
　　 测量是施工的先导，为配合施工的需要，测量技术人员必须做到：
　　 (1)熟悉设计图纸，清楚相关设计思路。
　　 (2)检查图纸，核实图纸的有关数据，做好施工测量的数据准备。
　　 (3)了解施上工作计划和安排，协调测量与施工的关系，熟悉施工工艺。
　　 2．熟悉现场实际
　　 测量人员熟悉现场实际是搞好施下测量的基本条件，要做到这一点就必须：
　　 (1)核查或检测施工控制点，以确保点位准确可靠。
　　 (2)了解工地范围的地形、地物状况。
　　 (3)掌握施工进展情况；避免施千对测量的可能影响，及时准确完成施了测量工作。
　　 (4)熟悉施工环境。
　　 3．加强测量标志的管理和保护，注意受损测量标志的恢复
　　 测量标志，包括控制点和放样点。其中控制点是施工测量的基础，放样点是施工的依据。由于施工的复杂性和多样性，往往有可能造成测量标志受损或丢失。因此测量过程中必须加强测量标志的管理、保护并及时恢复受损测量标志。
　　 第二节 测设的基本工作
　　 如前所述，测设上作就是把图上规划设计的建(构)筑物，按照设计的位置、大小在实地测设出来，即所谓施工放样(放线)。实质上就是将图纸上设计的建(构)筑物的特征点测设到地面上去。而点的位置是由于面位置及其高程所确定的，测设点的下面位置通常是通过测设水平距离和测设水下角米确定的。因此，水平距离测设、水平角测设和点的高程测设工作称为测设的基本工作。
 

Construction Survey Section Overview
1, the construction and principles of measurement tasks
General construction of medium-sized civil engineering at the start, before the topographic map must be designed, the design of the content discussed, modified, since the adoption of auditing can be carried out at the construction site lofting, only through the accurate setting-out in order to carry out the construction.
Shih Cheng-building on the small stage of the work carried out by a variety of measurements, called the Construction Survey. The basic task of construction survey is measuring instruments, according to the basic principles and methods of measurement, the construction drawings to design (structure) building material flat location and elevation, in accordance with design requirements, to a certain degree of precision to the ground-based measurements, S the corresponding symbol as a basis for construction; and in the construction process in a series of measurements to link up with and guide the construction between the various processes to ensure the project according to design requirements for construction of the building.
There are various facilities on-site construction (structure) building materials, and - as widely distributed and often are not at the same time started to build. In order to ensure that all the building (structure) building location and height of flat objects are in line with design requirements, connected with each other into a unified whole, construction surveying and topographic mapping, have to follow the "from whole to part, first and control over their detail" principle, Any construction survey work, we must first be laid on the construction site a unified plane control network, and then set up as a basis for measuring the various building (structure) building material position.
In addition to the above principles should be followed, the construction of the calibration measurement of the work is also very important, must take a variety of ways to keep the external sector and calibration work within the industry, to ensure construction quality.
Second, the contents of the Construction Survey
Construction survey throughout the construction process, including: the establishment of construction control network; in the construction process, at any time given to build (configuration) the direction of building construction materials, elevation and flat position; inspection building (structure) building materials Shih Under the compliance requirements and are free to correct and modify; in the construction equipment and industrial equipment installation phase but also under the process and installation design requirements given spatial location and direction; project is completed, in order to ease of management, maintenance and expansion carried out by Joon D measurement. Thus, construction survey from start to finish throughout the entire process of construction.
3, the construction characteristics of measurement
Compared with the topographic mapping, construction, measurements have the following characteristics:
(1) topographic mapping is on the ground surface features, topography surveying and mapping to the drawings, that is, from the surface to the drawings; while drawing on the construction survey is designed to build (structures) building materials to the corresponding ground-based measurements, it is, From the drawings to the surface.
(2) The topographic map of the precision and scale size of the fight off, the larger scale, the higher the precision of surveying and mapping; and construction of measurement accuracy depends on the nature of the construction, that is dependent on (structures) building the size, materials used , uses and building (structure) building material of the positioning accuracy. In short, the accuracy of setting out should be based on design requirements to determine the precision is too high, will lead to human, financial, material and time wasted, too low will affect the accuracy of measuring the quality of construction is located does not meet the requirements, resulting in rework waves praise, and even leading to the accident.
(3) The construction survey throughout the entire process of construction, heavy workload, assignments frequently, to make the process of error at any point, will affect the construction progress and quality, so the construction surveyors must have a high sense of responsibility.
(4) Shi 1000 on the kinds of multi-site, there are a large number of the top of the excavation and filling, the ground changes, there were all kinds of construction machinery vibration. The ground, underground and three at the same time high-altitude operations, complex, a greater impact on the measurements. For a range of measurement marks to be planted firmly, and the proper protection, regular inspection, if damage should be promptly restored.
4, the construction requirements for the work measurement
1. In close connection with the construction process
Measurement is the construction of the pilot, in order to meet the needs of the construction, measurement techniques must be done:
(1) be familiar with design drawings, clearly related design ideas.
(2) Check the drawings, drawings to verify the data and do the construction measurement data preparation.
(3) Understanding Shi working on plans and arrangements, coordinate the relationship between the measurement and construction is familiar with the construction process.
2. Are familiar with the actual scene
Surveyors are familiar with on-site facilities are actually doing a good job under the basic conditions for measurements, we must do this, they must:
(1) verification or inspection of construction control points to ensure that the points are accurate and reliable.
(2) understand the scope of the site topography, surface features status.
(3) control of construction progress; avoid Shi 1000 pairs of measurements that may affect the timely and accurate completion of the survey work facilities.
(4) be familiar with construction environment.
3. To strengthen the management and protection of the measuring mark, pay attention to restoration of damaged signs measured
Measuring signs, including control points and setting-out point. One control point is the construction of the basis of measurement, stake out point is the basis for the construction. As the construction of the complexity and diversity, often measured marks may result in damage or loss. Therefore, the measurement process need to strengthen the management of survey marks, protect and restore damaged and timely measurement marks.
Section II established the basic work measurement
As mentioned above, survey and design to make is to map the building planning and design (structure) building materials, according to the design of the location, size, set out in the field test, namely, the so-called construction layout (put line). Essence is to be built drawings to design (structure) building materials survey and design of the feature points to the ground up. The location of the point is due to face determined by location and elevation, the measured position set point is usually below the level established by measuring the distance and angle measurement based underwater m determined. Therefore, the horizontal distance measurement based, horizontal angle of elevation measurement and point-based survey and design work as the basic work-based measurements.