The Design Principle Of Drainage Structure Against Debris Flow Along Highways

Debris flow is a common geological disasters in the mountainous area. The mountainous area accounts for about two-thirds of the total land area in our country whose debris flow distribution is one of the more widely and severe disasters in the world . With the economy development and highway extension in the mountainous area , the debris flow disasters also increase in highway. The expenses for broken tao, rescue, maintenance and repair and the direct and indirect economic losses were counted hundreds of million yuan in our annual monsoon season,the accidents of casualties,equipment were destroyed and driving safety occur frequently,so it become the important factor of mountainous highway construction and operation management.The management of debris flow hazards in mountainous highway will be studied.Aiming at the common control structure of debris flow in highway--platoon guide structure of debris flow, this paper undertook a detailed quantitative study of the internal forces of row guide which comprehensively use of structural mechanics, mechanics of elasticity, the mechanics of materials, advanced soil mechanics etc discipline theory , focus on the design method of the bottom exhaust guide structure and top exhaust guide structure,provides theoretical support for the design of control structure in highway.The main achievements on the theory research of debris flow platoon guide structure in highway are as follows:(1)The big rubble stone impulse often causes the prevention structure destruction, but the commonly used debris flow big rubble stone impulse uses the ship raft impact on cause the computed result to be very big, is unable to utilize the project actual, this article use the energy method to carry on the computation to the debris flow big rubble stone impulse, this computational method has provided another kind of mentality for the debris flow prevention structure's design.(2)To collected the launder to carry on the analysis under debris flow impact action of force endogenic force, was the simplified computation, it was advantageous applied in the actual project, collected the launder to regard as the cantilever beam to carry on the endogenic force computation, the impulsive load has included in the mudstone fluid and the mudstone fluid the big rubble stone impulse. And the big rubble stone impulse not only uses the ship raft impact formula and carries on the computation based on the energy method inferential reasoning impulse formula.(3)Leads the structure V platoon in view of the commonly used debris flow platoon to lead the structure, based on V row of guide channel the Dutch pattern and the boundary condition, utilized bright is willing the earth pressure theory and the Winkler elastically foundation beam computation theory establishes V platoon to lead the structure spandrel wall and the tank bottom computational method, and carried on V platoon take the flat country debris flow prevention project as the example to lead the structure the design calculation.(4)Because above Winkler elastically foundation beam theory is very complex, does not suit actual in the project applies, to be advantageous utilizes the actual project, leads the bottom more-like platoon to the platoon to lead the structure tank bottom computational method - Winkler elastically foundation beam computation theory to carry on the simplification, uses the reaction straight line method to carry on the computation, this method supposes the ground reaction is distributed according to the straight line rule, its ground reaction graph under the symmetric load function is the rectangle, under the non-central load function is the trapezoid. Because this hypothesis had not considered the foundation and the ground distort uniformity, no matter therefore the load and distribution what state, the foundation rigidity and the soil mechanical properties how can the direct timber wood material mechanics center or the eccentric compression formula calculate the ground reaction, has the computation simple merit. Because this method has not considered between the foundation beam and ground distortion coordinated, thus its computed result is not precise. This article in carried on above the massive computation foundation to give the simplified coefficient which might refer, led the structure for the bottom more-like platoon the design to provide the reference.(5) In view of needs to use under the extreme terrain condition goes against more-like the platoon to lead the structure, this article opposite vertex more-like platoon leads the structure main body each part to carry on the endogenic force analysis in turn, is in turn: Trough body, structural support, foundation. In order to go against more-like the platoon to lead the structure the design to provide the rationale.(6)This paper gives a breakdown of the internal force analysis using the beam54 unit of large and general finite element software ANSYS on elastic foundation beam of base pass high-speed drainage structure and internal force and stress-strain analysis using beam4 unit and solid45 unit on the supporting system and the whole of upper pass high-speed drainage structure, and compares with the foregoing analytic solutions.