Monitoring settlement of construction works is extremely important and necessary surveying for each construction investment project. The monitoring of the settlement of the project helps the investor to manage and evaluate the quality and the changes that occur on the foundation of the project, if there is any special incident or the settlement of the building is within the limit for whether or not compared to the calculated values ​​in the design file.



Anchor point Subsidence monitoring is one of the tasks in the process of monitoring deformation of works, this is a very important focus including 3 main methods as follows:
Settlement monitoring
Horizontal monitoring
Through tilt
Through the article today, I will introduce the work of monitoring subsidence, you can learn the process of deformation monitoring work here:
>>> Learn about monitoring deformation of works

Requirements on accuracy in monitoring subsidence works
1. Construction phase

Depending on the characteristics of each construction work and the type of foundation performed under the project, the accuracy of the settlement of the construction is required as follows:

Type of construction and foundation
Accuracy
monitoring (mm)
Construction works on the base stone and the original half stone ± 1.0
Works on clay, sand and other stress-bearing foundation ± 3.0
Types of earth and rock dams with high pressure ± 5.0
Construction works on a sliding ground of ± 10.0
Types of earthwork works ± 15.0


2. Operation phase

Based on the level of displacement of the project, it is possible to set the accuracy of subsidence monitoring.
Cycle of subsidence monitoring

- Monitoring of deformation displacement works is a repeating measurement method which is performed many times on a construction work, each time is called a monitoring cycle. The period of implementation of the monitoring cycle will depend on the different types of works, each type of foundation and the characteristics of the level of shifting on the work and the construction schedule.

- The shifting monitoring cycles are divided into 3 phases: construction phase, finishing stage of operation and operation phase.

- During the construction phase, the monitoring cycle is carried out right at the beginning of the completion of the foundation, when the construction is not affected by the load and horizontal pressure. Subsequent cycles are carried out depending on construction progress and work load, usually from 2 to 4 months of measurement for 1 cycle.

- In the stage of finishing, operation, the cycles are determined depending on the speed of movement and characteristics of the operation of the project. The measurement time between 2 cycles can be chosen from 6 months to 1 year, the time between 2 cycles is set less when the work is gradually stabilized.

- During the operation and exploitation phase, the measuring time between 2 cycles can be from 6 months to 1 year or 2 years. When the construction is stable and the transfer speed is about 1-2 mm / year, it may stop monitoring. In case of abnormal mutations, it must be measured. In case of abnormal mutations, it is necessary to measure additional observations.

- The cycle should be monitored at the right time, so that it can reflect most clearly the law of shift, deformation and follow the process of technology, quality and method of evaluating results.