A study on the debris flow-induced impact force on check dam with- and without-entrainment

The destructive nature of debris flows is mainly caused by flow bulking from entrainment of an erodible channel bed. To arrest these flows, multiple flexible barriers are commonly installed along the predicted flow path. Despite the importance of an erodible bed, its effects are generally ignored when designing barriers. In this study, three unique experiments were carried out in a 28 m-long flume to investigate the impact of a debris flow on both single and dual flexible barriers installed in a channel with a 6 m-long erodible soil bed. Initial debris volumes of 2.5 m<sup>3</sup> and 6 m<sup>3</sup> were modelled. For the test setting adopted, a small upstream flexible barrier before the erodible bed separates the flow into several surges via overflow. The smaller surges reduce bed entrainment by 70% and impact force on the terminal barrier by 94% compared to the case without an upstream flexible barrier. However, debris overflowing the deformed flexible upstream barrier induces a centrifugal force that results in a dynamic pressure coefficient that is up to 2.2 times higher than those recommended in guidelines. This suggests that although compact upstream flexible barriers can be effective for controlling bed entrainment, they should be carefully designed to withstand higher impact forces.

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Experimental Study of the Debris Flow Slurry Impact and Distribution

Shock and Vibration ◽

10.1155/2018/5460362 ◽

2018 ◽

Vol 2018 ◽

pp. 1-15 ◽

Cited By ~ 1

Author(s):

Haixin Zhao ◽

Lingkan Yao ◽

Yong You ◽

Baoliang Wang ◽

Cong Zhang

Keyword(s):

Debris Flow ◽

Debris Flows ◽

Impact Force ◽

Influence Factors ◽

Flume Experiment ◽

Middle Point ◽

Laboratory Flume ◽

Critical Issues ◽

Maximum Impact Force ◽

The Impact

In this study, we present a new method to calculate debris flow slurry impact and its distribution, which are critical issues for designing countermeasures against debris flows. There is no unified formula at present, and we usually design preventive engineering according to the uniform distribution of the maximum impact force. For conducting a laboratory flume experiment, we arrange sensors at different positions on a dam and analyze the differences on debris flow slurry impact against various densities, channel slopes, and dam front angles. Results show that the force of debris flow on the dam distributes unevenly, and that the impact force is large in the middle and decreases gradually to the both sides. We systematically analyze the influence factors for the calculation of the maximum impact force in the middle point and give the quantitative law of decay from the middle to the sides. We propose a method to calculate the distribution of the debris flow impact force on the whole section and provide a case to illustrate this method.

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Efficiency of Slot-Check Dam Group on Debris Flow Control in Shengou Basin, Kunming, China

Landslide Science for a Safer Geoenvironment ◽

10.1007/978-3-319-04996-0_7 ◽

2014 ◽

pp. 37-43 ◽

Cited By ~ 3

Author(s):

Yuhua Zou ◽

Kaiheng Hu ◽

Xiaoqing Chen ◽

Wei Zhong

Keyword(s):

Debris Flow ◽

Flow Control ◽

Check Dam

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An experimental evaluation of impact force on a fiber Bragg grating-based device for debris flow warning

Landslides ◽

10.1007/s10346-018-1083-0 ◽

2018 ◽

Vol 16 (1) ◽

pp. 65-73 ◽

Cited By ~ 2

Author(s):

Shaojie Zhang ◽

Changxue Xu ◽

Jiang Chen ◽

Jun Jiang

Keyword(s):

Debris Flow ◽

Fiber Bragg Grating ◽

Experimental Evaluation ◽

Impact Force ◽

Bragg Grating

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Preliminary study of debris flow impact force on a circular pillar

Physical Modelling in Geotechnics ◽

10.1201/9780429438646-53 ◽

2018 ◽

pp. 1105-1110

Author(s):

A.L. Yifru ◽

R.N. Pradhan ◽

S. Nordal ◽

V. Thakur

Keyword(s):

Debris Flow ◽

Impact Force ◽

Preliminary Study

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Analysis of a debris flow after Wenchuan Earthquake and discussion on preventive measures

Thermal Science ◽

10.2298/tsci180811224z ◽

2019 ◽

Vol 23 (3 Part A) ◽

pp. 1563-1570

Author(s):

Zhi-Long Zhang ◽

Jing Xie ◽

De-Ke Yu ◽

Zhi-Jie Wen

Keyword(s):

Debris Flow ◽

Wenchuan Earthquake ◽

Preventive Measures ◽

Impact Force ◽

Site Investigation ◽

The Wenchuan Earthquake ◽

Formation Conditions ◽

National Road ◽

And Control ◽

Debris Flow Disaster

This paper addresses a debris flow disaster in Yingxiu town after the Wenchuan earthquake. Through site investigation and data review, the geography and geological environment of the basin and the development, formation conditions and activity characteristics of the debris flow in the basin are analyzed. Calculate and analyze the characteristics of the debris flow, such as gravity, flow velocity and impact force. According to the management idea of combination of blocking and discharging, this paper proposes to arrange three blocking dams in the main ditch, construct drainage gullies in the downstream accumulation section, and prevent and control the aqueduct in the intersection of the main ditch and the G213 national road, which will be similar to the earthquake in the future. It is provided as a reference for research and prevention of the debris flow.

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