Brief introduction to the author: Zhang shuoyu, technical engineer of CCCC bridge structural health monitoring center and Lu’an Jiaoke (Beijing) Monitoring Technology Co., Ltd., mainly engaged in infrastructure intelligent management and intelligent monitoring, Tel: 13161121286
. 
In the last article, I discussed with you the relevant contents of the bridge health monitoring scheme design
. 
After the general scheme review and bidding, we entered the important step of health monitoring construction engineering, which is an important guarantee for the success of the health monitoring system
. 
Construction Engineering in a broad sense can be divided into hardware system engineering and software system engineering according to the implementation method and nature
. 
This paper mainly discusses the construction of hardware system, and the general flow chart is as follows: Fig
. 
1 Division of using stages
.
It can be seen from the figure that the construction project of hardware system is mainly divided into three stages: first, preliminary preparation
.
The most important work in the preliminary preparation stage mainly includes two parts: first, the preparation of data files to ensure that there are laws to follow during the construction period; The second is equipment calibration and performance testing to ensure the accuracy of data sources
.
The data and documents mainly include: construction drawings deepened according to the design requirements, preparation of construction organization design, special construction scheme, etc
.
the site construction can be carried out after passing the review and technical disclosure
.
The content of construction drawing has been introduced in the first part; Construction organization design includes construction organization structure, construction technology, progress and guarantee measures, quality guarantee measures, health, safety and environment guarantee measures, etc; The special construction scheme mainly aims at the description and special design of some key and difficult construction
.
Equipment calibration and performance test mainly include: for the sensor, calibration is a very important step provided by the supplier to the customer
.
Only through calibration, can the measured value be kept accurate in the actual measurement; In addition, the on-line calibration of sensors is also the development trend
.
The performance test is mainly to network the sensors and acquisition equipment before entering the construction site, and collect the data to the server for long-term stability test
.
Fig
.
2 sensor measurement calibration II
.
Site construction stage mainly includes installation and debugging
.
Installation includes equipment storage, sensor installation, cable laying, acquisition station installation, lightning protection and grounding construction and other divisional works
.
The project requires equipment calibration and storage, data review before entering the site, including calibration report, etc; After entering the site, according to the use conditions, the sensor installation location, installation method, fixation method, protection measures, external wiring, identification and other cable laying bracket production and installation, bridge installation, power line / signal line laying, identification and other acquisition station installation, acquisition station fixation, protection, protection, identification and other lightning protection and grounding construction, lightning protection and grounding device, etc Installation of grounding wire Fig
.
3 installation design of tie rod displacement sensor Fig
.
4 sensor installation and identification debugging are divided into single debugging and joint debugging, and relevant debugging report shall be issued
.
Single debugging includes power supply, signal, data debugging, etc; Joint debugging includes data acquisition, transmission and storage, data display, playback and statistics, timing error, mean time between failures, data missing rate, data rationality verification, etc
.
Fig
.
5 Protection of acquisition station III
.
acceptance handover acceptance stage shall be carried out on the basis of self inspection of construction unit in sequence of sub item acceptance, performance acceptance and completion acceptance
.
Sub item acceptance: acceptance of each main sub item project
.
The type, model and quantity of the sensor, the installation angle and position of the sensor lead out the cable; Appearance, field filling; Working performance, initial data, fixed identification, archives, etc
.
Type, model and quantity of acquisition transmission cable and data transmission equipment; Successful connection, routing direction and turning radius, cable joint and protection measures; appearance; Function of data transmission equipment; The data transmission is stable and reliable, and the response delay time is short; Fixed marks, archives, etc
.
Collect the protection level, protection device, UPS, fixed identification, file data, etc
.
Performance acceptance: acceptance of the performance of sensors and acquisition equipment
.
It mainly determines the test run time, synchronous performance of data collection, transmission and storage of front-end equipment, integrity of monitoring data, test run report, performance test and debugging process record, performance acceptance data list
.
Completion acceptance: it is generally carried out within 3 months after passing the performance acceptance, and the hardware and software of the monitoring system shall be sampled; The completion acceptance documents should include: 1
.
Monitoring system design documents and design change records; 2
.
Site acceptance report of materials, equipment and software; 3
.
Sub item acceptance documents and relevant data; 4
.
Performance acceptance documents and relevant data; 5 random inspection report; 6
.
Records of abnormal events and handling during construction and trial operation; 7
.
Completion acceptance data list
.
Note: the above documents mainly refer to t / cecs765-2020 standard for construction and acceptance of structural health monitoring system
.
This is about the construction project
.
The next article will discuss with you about the design and function application of health monitoring software system
.
Looking forward to further communication and correction with you
.
Jianshixueshe@163.com2021 April 25, 2005.
.
