Abstract: A three-dimensional multi-point and multi-index early warning method for risk at a power grid tower in a landslide section, including: (1) classifying the risk level of each index; (2) obtaining the value of various indexes of the power grid tower in a landslide section during a certain period of time. (3) calculating the single-index measure of each index, and obtaining the evaluating matrix of the single index measure; (4) determining the weight of each index; (5) calculating the multi-index comprehensive measure of the landslide and power tower; (6) introducing the confidence level ? to determine the comprehensive risk level of the power tower instability; (7) performing early warning based on risk level. The invention greatly improves the warning accuracy of the landslide, and realizes the accurate judgment and warning of danger of the tower.

Abstract: A method of designing a box-type energy-dissipating section of a box-type energy-dissipating mudflow diversion flume. Firstly, the longitudinal gradient J of the flume and the roughness coefficient n 0 of a fully-lined flume bottom (1) are determined. Then, the parameters of the box-type energy-dissipating section are set, and related parameters are substituted into a formula for calculation, so that the overall roughness coefficient n of the flume is obtained. Further, the flow velocity of the mudflow is calculated by means of the Manning formula. Finally, the flow velocity of the mudflow is compared with the non-scouring and non-silting velocity allowed by the flume, and the design value of the box-type energy-dissipating section is obtained through final optimization. The method factors in the longitudinal gradient J of the flume, the length L of the box-type energy-dissipating section, the width b of the box-type energy-dissipating section, and the average diameter D of filler stones.

Abstract: A new experimental device for debris flow simulation, including a material supply device, a flow channel, a stacking groove, a pole, a first high-speed camera, a second high-speed camera, a fixing frame, and a sliding rail. The material supply device is used to release the debris flow simulation material to the flow channel, to realize the start of the debris flow simulation. The stacking groove is used for the accumulation of the debris flow. The pole is used to support the stacking groove and adjust the slope of the stacking groove. The fixing frame is used to fix the first high-speed camera. The second high-speed camera can monitor the movement of the debris flow. The invention can flexibly simulate the movement characteristics of various debris flow and obtain the test data, so as to provide data support for the subsequent study.

Abstract: A debris flow drainage channel is provided. The debris flow drainage channel is applicable to debris flows with large gully bed longitudinal slopes. The debris flow drainage channel has an upstream step section and a downstream step section. The debris flow drainage channel also has a step pool disposed between the upstream step section and the downstream step section. The pool section has a cable net cage bottom protection, a cable net cage buffer layer and block stones.

Abstract: A rapidly assembled debris flow sediment storage dam and a construction method are provided. The sediment storage dam has a main dam body with multiple prefabricated reinforced concrete rectangular boxes linked by vertical and horizontal connections. The top surface of each rectangular box is open, and the other five surfaces of the rectangular box are closed. Soil is used to fill each rectangular box. The main dam body is assembled above dam body foundations. Dam abutment foundations of the sediment storage dam and the inside slope of the dam body are filled with cement-laid stone masonry or concrete, while the top surface of the dam crest is also sealed using cement-laid stone masonry or concrete.

Abstract: The invention discloses a debris-flow prevention method by controlling debris-flow magnitude and avoiding to block main river. This method first adopts the drainage works for delivering debris flow in corporation with the transport of the main river; if the drained sediment cannot be transported by the main river, the blocking works are adopted; and if the sediment still exceeds the delivering capacity, the deposit stopping works are adopted. Compared with the prior art, this invention makes full use of the main river's transport capacity, gives priority to dredging and also reasonably distributes the sediment and deploys the engineering system, so as to realize the safe discharge of debris flow, and avoid the secondary disaster of “barrier lake” caused by the blocking of main river due to excessive discharge of debris flow and fully guarantee the safety of mountain towns, major projects and infrastructure located at the mouth of debris flow gully.

Abstract: A system of debris-flow drainage canal with cascaded sills is provided, which allows a high-efficient and low-cost realization of debris flow drainage and scour prevention. The canal contains two converging walls and a series of scour prevention sills, which are laid between the two converging walls. The sills are embedded to a certain depth and are evenly spaced and symmetrical to the centre line of the canal to form a cascaded structure for scour prevention. The drainage canal's width is 2 times wider than the sill's horizontal length along the cross-section. Compared with the prior art, this system can drain off a wide variety of flows from debris flow to flood and prevent debris-flow siltation even on a gentle slope. This system has a much higher stability and longer life of service. Moreover, this system can maintain the aquatic habitat in gullies and contribute to ecological restoration.