The bored reinforced-concrete column and a method of its erection
Details…
Lining structure solutions for subway stations:
1. In 1995 under the supervision of Pavel B. Yurkevich was undertaken a deep-through study of material consumption, stressed-deformed condition and efficient use of underground space in construction of single-vault underground subway stations by application of "diaphragm wall" construction method in relation with depth of construction and different schemes of single-vault lining structures. Separately investigated was the aspect of ensuring their watertightness both on the basis of construction practical experience analysis in some of the former Soviet Union cities and on the basis of theoretic research character of deformation in most critical joints of structures.
We have studied lining structure solutions for subway stations of two main groups and two sub-groups.
The first group includes reinforced concrete single-vault lining structures of subway stations allowing by their dimensions to be used for construction of any structures: platform sections, lobbies (vestibules) etc. In such case a sloping vault solutions were under review.
Second group included reinforced lining structures of subway stations, which circular vault was fit only for construction of platform sections and two-level service premise blocks but were not fit for construction of lobbies.
Separately reviewed were non-standard solutions referring to these groups but featuring of distinct structural peculiarities of certain lining elements.
To increase trustworthiness of obtained comparison results of options under review the vault light clearance height in crown, the vault height above rails heads, as well as geological conditions were taken equal for all types of lining.
Sub-groups included: first sub-group - linings without waterproofing of diaphragm walls, second - with waterproofing of diaphragm walls respectively. In first case ground water was not considered, in second case, its level was taken as 1 meter below top of structural concrete of diaphragm walls.
Since the invert effect influence on stressed-deformed condition and material capacity of lining in its unified and idealized medium for all types of lining is of secondary importance if compared to vault, then its rigidity and geometric shape were also taken as equal values.
These investigation materials were never published anywhere but we used them to improve the already known structures or to develop any principally new structures. The below-stated variants of structural solution of linings account for results of such investigation and incorporate improvements allowing to the client in each case to make a proper selection and optimize the accepted variant with regards to specific construction conditions.
In-situ reinforced concrete lining of single-vault subway station per Variant 1 applies to group 1 subgroup 1. Its prototype is a lining of a platform section of "Independence Square" station of Minsk Subway. The lining has hinge-type joints between invert and diaphragm walls and stiff joints with vault by means of exposed rebars.
(DWF-drawing, 17 Kb)
Precast with cast-in-place reinforced concrete lining of single-vault subway station per Variant 2 applies also to group 1 subgroup 1. Its prototype is a unified lining of Minsk Subway "Vostok" station. The lining has hinge-type joints with diaphragm walls of both precast with cast-in-place reinforced concrete vault and in-situ reinforced concrete invert. The gap between feet of extreme blocks of vault and diaphragm walls is filled with cement - sand mortar М200.
(DWF-drawing, 18 Kb)
Precast with cast-in-place reinforced concrete lining of single-vault subway station per Variant 2a is modification of previous structure of precast with cast-in-place reinforced concrete lining. The modification is in application of ribbed curve-surface slabs as middle blocks. The prototype is unified lining made at "Avtozavodskaya" station of Minsk Subway.
(DWF-drawing, 19 Kb)
In-situ reinforced concrete lining of single-vault subway station per Variant 3 is modification of Variant 2 with the only difference that the vault jointing diaphragm walls as hinge is constructed as in-situ reinforced concrete structure.
(DWF-drawing, 18 Kb)
Precast with cast-in-place reinforced concrete lining of single-vault subway station per Variant 4 applies to group 2, subgroup 1, non-standard. Its prototype is a lining of a platform section of "Krylatskoye" station of Moscow Subway. The lining has hinge joints with diaphragm walls of both in-situ reinforced concrete invert and precast reinforced concrete vault, executed as "running fallow-deer" type. This structural scheme allows to avoid problems with vault waterproofing and to use corridors above the vault to accommodate transit engineering utilities.
(DWF-drawing, 18.7 Kb)
Precast with cast-in-place reinforced concrete lining of single-vault subway station per Variant 5 applies to group 1, subgroup 2. Its prototype is a lining of a platform section of "Independence Square" station and "Vostok" station of Minsk Subway. The lining has hinge joints with diaphragm walls of in-situ reinforced concrete invert, rigidly connected by means of in-situ reinforced concrete protective waterproofing walls with precast and cast-in-place reinforced concrete vault, and lower parts of vault feet. The vault upper parts are rigidly connected by means of rebar outlets with diaphragm walls.
(DWF-drawing, 17 Kb)
Precast with cast-in-place reinforced concrete lining of single-vault subway station per Variant 5а is a modification of Variant 5 precast and cast-in-place reinforced concrete lining. Its prototypes are lining structures of a platform section of "Independence Square" station, "Vostok" station and "Avtozavodskaya" station of Minsk Subway.
(DWF-drawing, 19 Kb)
In-situ reinforced concrete lining of single-vault subway station per Variant 6 applies to group 2, subgroup 2. Structural scheme of this type of lining is similar to Variant 5. Its prototype is a lining of a platform section of "Molodyozhnaya" station of Minsk Subway.
(DWF-drawing, 18 Kb)
In-situ reinforced concrete lining of single-vault subway station per Variant 6a is a modification of Variant 6, and is executed with flat bottom invert and is designed for soil bases with quite high ratio of resilient ground reaction.
(DWF-drawing, 16 Kb)
In-situ reinforced concrete lining of single-vault subway station per Variant 6b is a modification of Variant 6 and is designed for stub track of subway.
(DWF-drawing, 21 Kb)
Precast with cast-in-place reinforced concrete lining of single-vault subway station per Variant 7 applies to group 2, subgroup 2, non-standard and is similar to lining Variant 4. The lining has hinge joints with diaphragm walls of in-situ reinforced concrete invert, rigidly connected with in-situ reinforced concrete protective waterproofing walls. The roof-vault structural scheme, the so call "running fallow-deer" rests as hinge type structure on protective walls and diaphragm walls. The vault feet are constructed with light windows allowing not only to diversify the architectural appearance of the station but also facilitate servicing of luminaries allowing access to them from communication walkway corridors over the vault.
(DWF-drawing, 19 Kb)
Precast with cast-in-place reinforced concrete lining of single-vault subway station per Variant 7а is a modification of lining per previous variant with the only difference that the invert bottom is made flat and is designed for soil bases with sufficiently high ratio of resilient ground reaction.
(DWF-drawing, 16 Kb)
It is on the basis of aforementioned investigation and design elaboration that in 1996 was designed a vaulted lining of underground four-level car parking located on Revolution Square in Moscow, having no analogous solutions in the world. We also proposed different variants of using of sloping vaults for underground parking construction.
(DWF-drawing, 83 Kb)
In-situ reinforced concrete lining of four-level underground parking per Variant 1 designed by double-vault scheme with unified geometry of formworks in each span and at each level. Concreting of two vaults at each level must be executed simultaneously by standard portions by width, proportionate to double spacing of longitudinal pylons.
(DWF-drawing, 19 Kb)
In-situ reinforced concrete lining of four-level underground parking per Variant 2 designed as single-vault scheme with unified geometry of the formworks at each level and with intermediate columns, concreting simultaneously with vaults. The columns are used not only as bearing supports of sloping shell vaults but also for adjustment of stressed-deformed condition of vaults by means of controlled, synchronous and pre-determined settlement of columns feet in progress of replacement of removable forms by temporary supporting props prior of concreting of upper vaults.
(DWF-drawing, 17 Kb)
In-situ reinforced concrete lining of four-level underground parking per Variant 3 designed according to schemes of two "running fallow-deer's" by making use of steel pipe supports - unremovable casing pipes. This structural scheme allows achieve a symbiosis of major advantages of column-type three-span and vault-type single-span schemes.
(DWF-drawing, 19.6 Kb)
With a purpose of efficient use of underground space and in order to solve problem of parking in major cities it is reasonable to construct underground parking lots over the subway stations and tunnels constructed by cut-and-cover method.
In-situ reinforced concrete vaulted lining structures of subway stations combined with underground car parkings may be constructed at intermediate stations
(DWF-drawing, 21 Kb) or at interchange stations
(DWF-drawing, 19.6 Kb)
2. In 1994 on the basis of Pavel B. Yurkevich's "know-how" a universal rectangular integral section of precast reinforced concrete lining for cut-and-cover tunneling was developed, its description is practically unknown in Russia since it was published only in official journal of International tunneling association (ITA) - "Tunnelling and Underground Space Technology" (Vol.10, No.3, pp.353-365, 1995) in English (article by P. Yurkevich "Developments in Segmental Concrete Linings for Subway Tunnels in Belarus").
Application field of universal section: construction of communal and transport tunnels by cut-and-cover method, including subway tunnels located at straight and any curve-lined route sections.
The universal nature of rectangular integral section is ensured by symmetrical inclination of end surfaces in two planes in relation to a secant plane. This allows for rotating the rectangular whole section in relation to its longitudinal axis, as well as its vertical and horizontal axes by 180°.
A universal section is formed by six planes: four planes perpendicular to one another, forming its outer surface and two inclined planes - end planes. In order to facilitate understanding of principals lying in making the form of a universal section, all its four outer surfaces are painted different color and inclination of end surfaces is artificially made higher.
Section geometric sizes are calculated depending on required inner size as well as accepted minimum radiuses of horizontal and vertical curves of the tunnel route.
At route straight section each next section is installed at 180° rotation towards previous one around tunnel horizontal and vertical axes simultaneously.
See central tunnel fragment on picture.
At route turning left on horizontal minimum radius curve each next section is installed with 180° rotation towards the previous one around horizontal tunnel axis and with left-side radial orientation of inclined end sections at the same time.
See left tunnel fragment on picture.
At route turning right on horizontal minimum radius curve each next section is installed with 180° rotation towards the previous one around horizontal tunnel axis and with right-side radial orientation of inclined end sections at the same time.
See right tunnel fragment on picture.
At route ascending on vertical minimum radius curve each next section is installed with 180° rotation towards the previous one around vertical tunnel axis and with upper radial orientation of inclined end sections at the same time.
See left tunnel fragment on picture.
At route descending on vertical minimum radius curve each next section is installed with 180° rotation towards the previous one around vertical tunnel axis and with lower radial orientation of inclined end sections at the same time.
See right tunnel fragment on picture.
By means of alternating sections installed according to principles of forming straight-line and curved-line sections of the rout it is possible to fit in any curves of any radius - higher than the minimum radius.
The distinct feature of tunnel lining by making use of rectangular universal whole sections is a complete absence of vertical joints, which allows high spatial rigidity of the system, involvement of effect of friction forces on inclined end surfaces.
With account to mutual character of adjacent sections work the reinforcement may be of unified type too. If necessary, in a single form-mould they make items of two modifications, which in terms of reinforcement account for differences in stressed condition of a roof and invert.
An important advantage of lining is its controlled constant value of jointing gaps allowing apply section joints prestressed by bolt (screw) connections with rubber gaskets.
