Pobierz pełny numer 1/2010 S&E - Structure and Environment - Kielce

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ROAD SUBGRADE EMBANKMENT DEFORMATIONa situation, when the water from the overdampingzone under the roadway paving through the unfrozencoat under the wayside and the upper part of fill slopecomes into the filtration flow, which flows in thesurficial belt of the slope.At some time the soil overdamping reaches thelevel when, the shearing force exceed restrainingforces. So there happens a shift – local deformationin the form of slope gutter.As regards sand the possibility of shift deformationis worsened by its tendency to attenuation in aqueousstate. Attenuation often happens [5] under theinfluence of filtration flow on the sand structure, inparticular in case of dynamic character of filtrationforces. Recently settled refuse stone of earthworks isvery sensitive to the dynamic forces. Dynamic effectsusually cause small shift of sand-grains, which causesand fluidization.In case of sand fluidization on the slopes, instead ofvertical displacement of sand-grains in the process ofsand settlement, there occurs considerable relative flatand vertical displacement of values as a consequenceof running ground dispersion. In case of sufficientsurface slope the burdens rush in the form flows to thelower areas, forming the covers, filling the cavitiesand hollows.Deformation ratio depends on the rate of dynamiceffects. Earthquakes can cause passing of sand intodilute state on the large area. The effects of explosionsand vibration are caused only by local fractures ofarea structure, quite close to the whence of dynamiceffects. Very often the fluidization event happens incomparatively small scales, for example, in the eventof people walking or vehicle passing over the surfaceof loose water- saturated sands [5].Fluidization is native to all quite loose granular soilsof any grain size. However due to a larger permeabilityto water the retention time of coarse-grained soils indilute state is less, than that of compact-grained andthat is why the fluidization practically never occursthere.The danger of fluidization for the resistibilityand structural competence is defined not by thefact of fluidization, but by the character of itsflow. The dwelling time of sand in dilute conditionand toughness of burdens influences the possibleconstruction displacement.The rightfulness of theoretical considerationsconcerning the reasons for formation of localdeformations on the slopes of grade level of roads wasconfirmed by the results of full-scale measurementsof water content and soil (sand) density on the fillslopes of roads «Don» (km 103-104), built fromfine sand of the borrow pit «Martemianovo» of Tularegion (filtration coefficient 1-3 m/day, gradationfactor -1,67). Embankment height – from 1.5 to 8 m.The research was carried out in the years 2001-2005.Water content and soil density on the slopes weredefined at depth 0, 20, 40 and 60 cm during differenttimes of the year. The depth was counted from thelower surface of top soil.The research was carried out in field and laboratoryconditions with the use of certified appliances. Thecharacter of coat moisture gradient of the slope partduring the spring months is shown on Figure 5.Fig. 5. Coat moisture gradient of the slope part of gradelevel in spring 2004 year. km 104 а/r «Don». 1-5 – pointon slope contour: 1 – on the edge, 5 – embankment foot,2-3 – passing pointsTable 2. The character of placement of thawed and frozenlayers on the slope of the fill in the first half of the dayMarch, 2004, km. 104 а/r «Don», depth of fill 8 m, sloperatio 1:1.75. Slope orientation - south, air temperature atnight -10°С, day +5°С№ layer Soil state in the layer Layer height, m1 Frozen ground 0.03 – 0.052 Hydromorphic soil 0.05 – 0.103 Fluidity soil 0.05 – 0.104 Frozen soil 0.15 – 0.205 Non frozen soil –The fact of water flow in the soil (filtration flow)was photographed (Fig. 6).35
M. V. Nemchinov, A. S. Men’shovFig. 6. Water filtration on the border of frozen andunfrozen soil (km 104 а/r «Don», 14.03.2004)Density measurements, carried out simultaneouslywith the humidity estimation showed that the soil onthe slopes is in quite friable state (Table 3).Table 3. Soil density and humidity of the fill slope on 104km road «Don» (average rates). Slope orientation – south.14.03.2004№measurementpoint12345Depth ofmeasurementpoint, cm0-20-40-600-20-40-600-20-40-600-20-40-600-20-40-60Coat densityg/cm 3 Coat humidity %1.831.801.761.871.851.851.831.871.831.801.761.871.831.801.761.871.761.831.831.8514.513.817.315.710.012.515.115.79.112.516.017.510.912.215.615.013.014.016.217.5Note: Optimum density for this sand is 1.89 g/cm 3 ,optimum humidity – 10.9%.Actual values of compacting factors (0.93-0.95-0.97) during the first 2.5 years of slope work (0.93-0.95 – 0.97) turned out to be lower than regulatoryvalue (min 0.99), which certifies soil high porosity onthe fill slopes.The research of dynamic effects of automobiletransport on the soil of the slope fill parts was carriedout at 104 km а/r «Don» (depth of sand fill – 6-8 m)and 94 km МКАR (depth of sand fill 2 m). On theа/r «Don» convulsion in coat generated by passageof single-unit truck of the mass 22 t with the speedof 50, 60 and 80 km/h, at Moscow Ring Motorwaythere was moving a real traffic flow with the intensity(in one direction) 6480 veh/h (km 9) and 7200 veh/h(km 14). The carriageway of the road «Don» has 4lanes (two lanes in each direction), at Moscow RingMotorway – 4 lanes in each direction. Shouldersat 1.0 m from the upper edge of embankment arehardened by plant formation. In both cases the theroad pavement made of asphaltic concrete, theroadbase – of low cement content concrete, base – ofsand.Vibrational impact of automobiles on the soil ofgrade level was studied in dry weather, in July underthe temperature of +23°С and in November underthe temperature of +4°С. There were registeredmean square and peak heights (X, Y, Z) of vibrationacceleration. Axle X is directed perpendicularly tothe road axle. The measurement time amounted to 5to 10 minutes and included the automobile drive tothe measurement point and automobile removal.Fig. 7. Curve of the soil particles flow (mm) as a result ofoperation of single load. Summary constituent, disturbingfrequency 10 HzThere were made measurements (the values ofvidroaccelerations), processing of the results receivedaccording to the finite element method enabled todefine, that the vibration impact on the slopes forthe conditions discussed in case of problem solvingon normal stress amounted, average, from 0.1 upto 0.044 kg/cm 2 , tangentially – from 0.04 to 0.001kg/cm 2 . Value peaks fall within the upper and lowerslope part, which suggests the increased load in thesezones. The movement of soil parts amounts to 0.6 upto 0.2 mm and on the whole uniformly decreases inproportion to the standing off pumping source (fromthe cover of the road) (Fig. 7).36
Page 3: EDITORIAL BOARDMain Editor Jerzy Z.
Page 12 and 13: RESISTANCE OF THE PAVEMENT TO WATER
Page 14: RESISTANCE OF THE PAVEMENT TO WATER
Page 19 and 20: RENÁTA BAŠKOVÁTechnical Universi
Page 21 and 22: Renáta Bašková, Ryszard Dachowsk
Page 23 and 24: Renáta Bašková, Ryszard Dachowsk
Page 25 and 26: MAREK IWAŃSKIGRZEGORZ MAZUREKKielc
Page 27 and 28: Marek Iwański, Grzegorz MazurekIt
Page 29 and 30: Marek Iwański, Grzegorz MazurekThe
Page 31 and 32: Marek Iwański, Grzegorz MazurekMar
Page 33 and 34: M.V. NEMCHINOVA.S. MEN´’SHOVMosc
Page 35: M. V. Nemchinov, A. S. Men’shovgr
Page 42 and 43: ŁUKASZ J. ORMANKielce University o
Page 44 and 45: POSSIBILITY OF THE APPLICATION OF M
Page 46 and 47: POSSIBILITY OF THE APPLICATION OF M
Page 48 and 49: MICROCLIMATE IN A FLAT WITH ADDITIO
Page 54 and 55: JOLANTA LATOSIŃSKAKielce Universit
Page 56 and 57: THE ASPECT OF WASTE MANAGEMENT IN M
Page 58 and 59: THE ASPECT OF WASTE MANAGEMENT IN M
Page 60 and 61: EWA ZENDER-ŚWIERCZJERZY ZBIGNIEW P
Page 62 and 63: CALCULATION OF TEMPERATURE IN VENTI
Page 64: „ENERGIS” - intelligent buildin

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