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IN CASE, THERE IS NO UNDERGROUND WATER, CARYING POWER IS POOR BECAUSE OF LAKING :
With the aim of preventing the deficiency, the uses elusion of poor ground and in digged section “Free Drainage Material” shoul be suggested. In case the filling material permeable having granular attribute, will not necessary to use free drainage material.
FREE DRAINAGE MATERIAL
Sieve (mm) The percentage of Passed Material
3” (76 mm) 100
1 1/2” (38 mm) 70-100
3/4” (19 mm) 40-100
3/8” (9.5 mm) 20-70
No:4 (4.75 mm) 0-40
No:8 (2.38 mm) 0-12
No:200 (0.074 mm) 0-3
THE CASE OF BEING GROUND HAVING THE INFLATABLE PROPERTY AT SPLITTING BASES
In case of being ground having the inflatable property at splitting base, by using the percentage of inflatable, and the inflatable pressure values, the orders of inflatable must be determined. In long tule, after opening the railway for navigation, in order not to break down the superstructure, the deformation which will form because of inflatable, must not exceed 5 cm. The drainage cautions which will allow to approximate at most 1.5 m to superstructure base level of water nap must me projected.
IN PASSING POOR GROUND, PROJECTING THE ADVANCED GROUND RESTORATION
At unsolved problems by the poor ground thickness is much, and, by forming restoration layer , shallow digging; the restoration of advanced ground alone or together with the shallow ground must be projected. Advanced ground restorations are considered for wadding, bridge approach wadding base ground, bridge based grounds, fundamentally, are necessary for accelerating the sittings, decreasing, increasing the carrying power, increasing the slope stability.
For the ground restoration that will be projected, the cutting that will be used relates to the width section, it must be the most critical cross-section, for the changed ground and load conditions must be done calculations according to different cross-sections.
The following alternative applications must be evaluated in order in ground restoration projects:
-Preloading and surcharge
-Loading in stages
Before building the road and road structure, the loading ground previously is PRELOADING; on the building loading that will affect the ground continuosly, in addition making extra loading is SURCHARGE LOADING; in both cases, the orders and their durations of the sittings that will be formed by preloading on ground and after loading, will be showed the effect of road or road structure that will be calculated.
Loading in stages is the buiding wadding in stages in high that the ground can carry, in each stage, the ground sittings under the certain wadding height, will be completed, the wadding must be projected in order to increase the project height, after the sliding leaning will reach to wanted value.
The details of the measuring system of the amount of sitting must be written in report.
In case of the suggestion of loading in stages, the stability analysis or carrying power calculations for each stage, must be done, the safety number at the building stages stability analysis must be taken in static case GS³1.2 . When necessary, to determine the restoration at the ground parameters, must be suggested research study after stages.
At the vertical drain and stone colon calculations, the duration of openning the road for navigation must be take into consideration, the position of vertical drain (its location, its range, its tall etc. ) must be given and must be prepaired application threader.
In case of suggesting ground enjection and jet-grout, in order to satisfy the restoration at the required attribute, the necessary enjection type and its pressure, the flow of pump, the speed of withdrawing, the rotation speed, the type of enjection equipment, cement leaning, water/cement ratio etc. the parameters unique to enjection application, must be written in the report by providing the selection of equipment and method. For these methods, with the aim of controlling the parameters estimated in project, the trying application, the criteria belong to studies which are done for the quality control must be given in the report.
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