Optical fiber sensor intelligent concrete [3], that is, the optical fiber sensor embedded in the key parts of concrete structure by human or his array, detects the changes of internal stress and strain contained in the carbonation process of concrete, as well as the real-time monitoring of deformation, crack and expansion caused by external forces, such as fatigue. Optical fiber is easily influenced by external environmental factors, such as temperature, pressure, electric field and magnetic field, which causes changes in light wave volume, such as changes in light intensity, phase, frequency and polarization state. Therefore, it is found that if we can measure the change of light quantity, we can know that light waves cause changes in physical sizes such as temperature, pressure and magnetic field. Therefore, one

Is the optical fiber sensing technology. In recent years, the research on the application of optical fiber sensors in the detection of reinforced concrete structures and buildings will be carried out at home and abroad, and the internal status of optical fiber sensing technology for the occurrence and development of stress, strain and cracks in concrete structures will be carried out, including the monitoring of concrete hardening process and long-term monitoring of structures. The application of optical fiber sensor provides intelligent real-time state and online nondestructive testing means for buildings and internal structures, which is beneficial to structural safety monitoring and overall evaluation and maintenance. So far, optical fiber sensors have been applied in many projects. A typical construction project is a Canadian double-span highway bridge named Beddington Tail, which is used to monitor the internal strain. Dam vibration monitoring of Winooski a hydropower station in USA: Domestic projects include the monitoring room of Hongcao Bridge on Chongqing Yulong Expressway and the long-term monitoring and security system for evaluation of Wuhu Yangtze River Bridge.

1.2 self-tuning intelligent concrete

Intelligent concrete has self-regulating effect and power performance effect. In addition to the concrete structure under normal load, people also hope that it can adjust its bearing capacity and alleviate structural vibration during natural disasters such as typhoons and earthquakes. However, concrete itself is an inert material, and to achieve the purpose of self-adjustment, it must have component materials with composite driving functions, such as shape memory alloy (SMA) and electrorheological fluid (er). If the shape memory alloy with shape memory effect (SME) is given a tensile plastic deformation beyond the elastic range at room temperature, when it is heated at least beyond the allowable phase transition temperature, the original residual deformation can disappear and return to its original size. Shape memory alloy is embedded in concrete. By using the temperature sensitivity of shape memory alloy and the function of restoring the corresponding shape at different temperatures, the internal stress of concrete structure is redistributed and a certain prestress is generated through the change of shape memory alloy under the disturbance of abnormal load, so as to improve the bearing capacity of concrete structure.

Electrorheological fluid (ER) is a kind of two-way adhesive change that can control its rheological properties such as viscosity and elasticity by external electric field. Under the action of external electric field, electrorheological fluid can become a solid gel with chain or network structure within 0. 1ms, and it will fully solidify with the increase of electric field intensity, and its rheological state can be restored when the external electric field is removed. In the composite electrorheological fluid of concrete, electrorheological fluid takes advantage of this rheological effect. When the concrete structure is attacked by typhoon and earthquake, it adjusts its rheological behavior internally, changes the natural frequency and damping characteristics of the structure, and achieves the purpose of slowing down the vibration of the structure.

Some buildings have strict requirements on indoor humidity, such as various types of exhibition halls, museums and art galleries. In order to achieve stable humidity control, it often needs many humidity sensors, control systems and complex wiring. , the cost and maintenance costs are high. Japanese scholars have developed to automatically adjust the ambient temperature of concrete materials to realize the humidity detection of indoor environment, and adjust it according to its requirements. The key component of the humidity environment automatic adjustment function brought by this concrete material is zeolite powder. The mechanism is as follows: Zeolite contains calcium silicate (3-9) X 10- 10m pores. These pore waters can selectively adsorb N0x and S0x gases. The selection of zeolite types can prepare concrete composite materials that can automatically adjust the required relative humidity in line with practical applications. It has the following characteristics: moisture absorption is preferred; Where the water vapor is low, its absorption capacity is large; Smoke and moisture release are related to temperature, with the temperature rising to release moisture and the temperature falling to release moisture.