Study On Sand Disaster Prevention And Treatment Measures In The Golmud-lhasa Section Of Qinghai-Tibet Railway

Since the opening of Golmud-Lhasa section of Qinghai-Tibet Railway, sand disasteralong the railway had been increasely worsening. With the implementation of sand preventionengineering, sand disaster along the railway had been relieved to some extent. But if we wantto eradicate the sand disaster, improving the sand prevention measures and perfecting the sandprevention system are needed.On the basis of field investigation, considering the sand flux and wind speed data, thispaper summarized the characteristics of the Qinghai-Tibet Railway sand disaster and analyzedthe characteristics of Qinghai-Tibet Plateau sand flow and sand disaster causes. With the fieldtests, wind tunnel tests and numerical simulation, we made a evaluation of existing sandprevention measures at the same time. In order to resolve the deficiencies of existing sandprevention system and measures, we make some suggestions of improving the sandprevention measures and perfecting the sand prevention system.The main conclusions are：(1) Sand disaster occurs mainly from November each year tonext May.It’s mainly located in the Hongliang River, Xiushui River, Beilu River, TuotuoRiver, Tongtian River and Zhajiazangbu River’s valley and two sides, Cuona Lake as well.(2)The main reasons of sand disaster along Qinghai-Tibet Railway. The Qinghai-Tibet Plateau’sdesertification and river and lacustrine sediments provide the material base for the sanddisaster. The Qinghai-Tibet Plateau’s strong wind climate in winter and spring provide theimpetus for the sand disaster. The Qinghai-Tibet railway disturbs the nomal movement of thesand flow and results in the sand deposition near the railway.(3) The Qinghai-Tibet Plateausand flow characteristic is that the sand flow moves mainly close to the ground.1meter is aturning point. The sand flux below1meter of the total sand flux accounts for more than90%, but there is a sharp decline in the sand flux above1m.(4) The high vertical-type PE net sandbarrier has played a very important role to curb the sand disaster spread, but it is easilydamaged. Sleeper-type sand barrier is the best sand wall of sand prevention measures;Hanging-type concrete sand barrier is slightly better than inserting-type concrete sand barrier;Bell-type sand barrier is far worse than several others.(5) The low vertical-type PE netcheckerboard barrier is slightly better than rock checkerboard barrier.(6) The reasonableinterval of the hanging-type concrete sand barriers and the inserting-type concrete sandbarriers should be23.5H (H is the height of the sand barrier).The reasonable interval of thevertical-type PE net sand barriers should be26H (H is the height of the sand barrier).(7) Theformula of the sand barrier height is H=k·h. Where H is the reasonable height of the sandbarrier, h is the height of most sand flux, k is the adjustment factor.(8) The ratio of PE netcheckerboard barrier’s height and width should be greater than1:5for Qinghai-Tibet Railway.The main innovation points are：(1) Summarizes the characteristics of the Qinghai-TibetPlateau sand flow by the positioning observation.(2) Evaluate the existing sand preventionmeasures, and give some suggestions for improvement.(3) Give some methods to determinethe three design parameters including reasonable height, interval of sand prevention measuresand specification of PE net checkerboard barrier.