供水、发电；清洁能源开发；水利水电工程开发与运营管理；水利水电工程代建管理技术服务；水利及水电工程建设咨询；自有机械设备租赁（除融资性租赁）；公路桥梁建设管理；种、养殖（除种畜养殖）；物资供销（国家限制的除外）；酒店经营；房地产开发；自有房屋租赁；CDM项目开发。（依法须经批准的项目，经相关部门批准后方可开展经营活动）
The volute of hydraulic turbine unit in hydropower engineering plays an important role in ensuring the uniform water supply of guiding water mechanism and reducing the working intensity of guiding water mechanism. In the process of long-term operation, the concrete volute often has defects such as voids, cracks, non-compactness and honeycomb. If not dealt with in time, the defects will affect the safety and durability of hydraulic concrete components. Therefore, it is particularly important to carry out health diagnosis on the concrete volute. In this paper, guided by the idea of combining network general detection and fixed-point inspection, based on different technical principles, different characteristics, different detection scales and different detection accuracy, the comprehensive geophysical exploration methods, such as the ultrasonic shear wave reflection of 3D imaging technique, the pulse echo technique, the acoustic reflection technique, the ground penetrating radar（GPR） technique are used to comprehensively detect the concrete quality around the volute and the contact condition of the steel lining on the top of the volute and concrete. The detection results can provide detailed information of concrete defects around the volute, so as to provide data services and decision support for the health diagnosis of the concrete volute. Practice has proved that the comprehensive geophysical method is an effective technical means to realize the defects detection of concrete volute, and it is worthy of popularization and application in practice.
In the process of long-term operation of water conservancy projects, the concrete components will suffer from abrasion, cracks and other damages. If such problems are not handled in time, the safe operation of water conservancy projects will be seriously affected. Based on the difference of wave impedance caused by the internal defects, we can detect the internal defects of concrete by ultrasonic shear wave reflection 3D imaging method. This method has the characteristics of shear wave detection, array coupling, phase-controlled array imaging, synthetic aperture focusing and so on. Under the configuration of multiple transmitters and multiple receivers, it not only has high signal-to-noise ratio, strong resolution and strong penetrating power, but also improves detection efficiency. Through the application of the ultrasonic shear wave reflection 3D imaging technique into the fine detection of concrete cracks of hydraulic concrete structure and the inner side of spiral case, which provides effective data support for subsequent maintenance and repairing. Practice has proved that the ultrasonic shear wave reflection 3D imaging technique has a good application effect in the diagnosis of cracks, voids and other hydraulic concrete defects, and it is worthy of application and promotion in similar cases.
