Designing and Foundation Works of the Solid-Cast Reinforced Concrete Slabs Under Complex Geological Engineering Conditions

ABSTRACT

Under complex geological engineering conditions, the foundations of buildings or structures are the most cost-intensive constructions (the costs for erection reach up to 15–20 % of the total reinforced-concrete expenses). At present, the matters of designing and calculation of solid-cast reinforced-concrete foundations for the purpose of reduction of the steel and concrete consumption as well as their cost are vital.

The article considers the peculiarities of the engineering-geological structure of the construction site, physical and mechanical characteristics of soils and matters of the engineering preparation of the base for casting-place reinforced-concrete foundation slabs under confined space conditions of the residential complex on the plots at the address: town of Khimki, Moscow Region (two 24-storeyed houses with the two-level underground parking and 17-storeyed residential house with underground parking). The efficient technology for compaction of weal soils is proposed, the actual soils characteristics obtained after the technology of performance of the works for the base compaction, the results of the foundation slab settlement calculation are provided and the results of comparison of the actual and design settlements of the foundations of the above residential houses are presented. Since it is practically difficult to take into account all the factors when calculating and designing the foundations, the geodetic observations of the foundation settlements were performed to check the expected deformations of the residential houses being designed under complex geological engineering conditions. The analysis of the actual and design settlements has shown that the actual settlements of the foundations are considerably less than those obtained according to the calculation during the designing that confirms in our opinion the correctly chosen technique of the base for the foundation slabs. At present, the settlements of all the constructed buildings have been stabilised and have not exceeded the maximum allowable values as follows from the results of the geodetic observations.

Keywords: foundation, cast-in-place reinforced-concrete slab, soil, characteristics of soils, settlement, base compaction technique, static probing, plate-bearing test.

For citation: Seskov V., Okladnikova A., Bannikov D. Designing and Foundation Works of the Solid-Cast Reinforced Concrete Slabs Under Complex Geological Engineering Conditions. In: Contemporary Issues of Concrete and Reinforced Concrete: Collected Research Papers. Minsk. Institute BelNIIS. Vol. 8. 2016. pp. 253-269. https://doi.org/10.23746/2016-8-15




References:

1. Rukovodstvo po proektirovaniyu plitnyh fundamentov karkasnyh zdanij i sooruzhenij bashennogo tipa [Directive for design of slab foundations of framework buildings and towertype structures]. M: NIIOSP im. N. M. Gersevanova Gosstroya SSSR, 1984. 263 p. (rus)
2. Osnovaniya zdanij i sooruzhenij Aktualizirovannaya redakciya SNiP 2.02.01–83*: SP 22.13330.2011[Bases of buildings and structures. Actualised edition of Construction Rules and Regulations (SNiP) 2.02.01–83*]. M: Ministerstvo regional'nogo razvitiya Rossijskoj Federacii, 2011. 156 p. (rus)
3. Grunty. Metody polevyh ispytanij staticheskim i dinamicheskim zondirovaniem [Soils. Methods of field tests by static and dynamic probing]: GOST 19912–2012. M: NIIOSP im. N. M. Gersevanova Gosstroya RF, 2014. 22 p. (rus)
4. Grunty. Metody polevogo opredeleniya harakteristik prochnosti i deformiruemosti [Soils. Methods of field determination of the strength and deformability characteristics]: GOST 20276– 2012. M: NIIOSP im. N. M. Gersevanova Gosstroya RF, 2012. 90 p. (rus)
5. Grunty. Polevye ispytaniya. Obshchie polozheniya [Soils. Field tests. General provisions]: GOST 30672–2012. M: NIIOSP im. N. M. Gersevanova Gosstroya RF, 2012. 11 p. (rus)

ISSN 2076-6033