By  constructing  a  pavement  with  composite  edging.  Part  3
  ► Materials
  ► Equipments
  ► Tehnologies
  ► Information
  ► Contact us
  ► Home

 Site Search




 Information for builders

 The new articles

Protect the surface of the concrete floor
To protect the concrete floor, which is operated in the normal mode, or is subject to wear in areas with high traffic, there are several ways to protect the surface.
   Comparable ways: their cost, appearance and ability to perform the task to protect.
   In this article, we consider three ways to finish and protect the floor. Each of them has its advantages and disadvantages.
   Thin fil...

Finishing compositions based on water glass. Part 3
When used as part of exhaustion moderator comes coagulation and solidification of liquid glass. However, due to the presence in the composition of Portland cement with a finishing time is an increase strength of the coating due to hydration of cement minerals. Thus from colloids formed during the coagulation liquid glass are actively assigned to the water for hydration of cement, a porous media formed tumors filled Portland cement, which leads to...

Finishing compositions based on water glass. Part 2
Studies in Berlin Institute Federal institute for Materials Research and Testing, show that the average density of 1730 kg/m3 brick large proportion of pores having a size in excess of 1 micron is more than 90% [3] and they are responsible for the increased migration of fluids through brickwork.
   Most fully meet these requirements structure obtained by coagulation and water-soluble potassium silicate forming silica with a high sp...

Modernization and repair of self-propelled machines. (3)
Hardening electrolysis BORATING hinge pins and bushings mates working equipment hydraulic excavators EO-4121 (EA-4321) gives an increase in wear resistance 4-6 times compared to the bulk quenching details.
   Taking into account the high wear resistance of brazed blades, hardened sintered alloys (see Table 1), are recommended for carbide knives dumps graders DZ-122 and RS-98, combined machine E-405 based on KAMAZ, for front dumps a t...

Specialized exhibition Architecture. Construction (END)
Mari-lime brick and gas silicate blocks
   JSC "MZSK" produces silicate brick and a half, color (white, yellow, black, red, blue, green, brown).
   For the production of silica brick used quartz sand from quarries near the plant. Limestone enters the factory with Dobryatinskogo deposit Vladimir region. Silicate brick (Table 1) is used for masonry exterior and interior walls of buildings and structures, as well as ...

Geophysical processes primers and security. Part 5
In the center of Moscow can distinguish vertical structure comprising a crashing into the Earth`s crust magma elongated cylinder (Fig. 2) [5]. In the center section marked lack of extensive vertical zone converted waves ("blind spot"), going from the depths of 70-80 km to 7.5 km. Such "blind spots" are characteristic of the earth`s crust with the introduction of monolithic dense mantle rocks such as gabbro, diabase, etc. In such a zone Tashkent e...

Finishing compositions based on water glass. Part 1
The quality of the decoration of buildings for new construction and reconstruction depend not only on their aesthetic, but also the operational parameters, as good-quality finish - a guarantee of durable service basic designs, long maintenance-free operation, the costs for maintenance and care. Traditional binders used for the production of finishing compositions, liquid glass is widely used, but it has some drawback: coatings based on it gaining...

On possible amendments to the equation Griffiths
Griffith presented a picture of destruction allowed to formulate the problem of determining conditions of the beginning of crack propagation and find its general solution.
   As seen from the above schemes, in the process of crack propagation material directly adjacent to it "coasts" unloaded relaxes. This means that the stress and strain it decreases, and the elastic energy stored earlier in this area of ​​the body is re...

Construction skyscrapers - the requirements of modernity. Part 4
The program is a high-rise building in Moscow
   The project is now a high-rise building in Moscow is implemented in two main areas: the construction of business center "Moscow City" and implementation of the program of the Government of Moscow "New Ring of Russia."
   1. Moscow international business center "Moscow - City"
   The project includes the construction of buildings on the territory of abou...

Degree project - beginning of the road. (3)
Given the great diversity of subject matter and content of diplomas in various specialties, the jury is faced with great difficulties in determining the winners - "Who better violinist or a dancer?". Nevertheless, often based on emotional perception and can estimate the relevance and novelty, and the author`s contribution to the thesis project or job. Absolute winners in recent years have been graduates of Rostov CSO GASU St. Petersburg, Nizhny N...


 Information for builders



 By  constructing  a  pavement  with  composite  edging.  Part  3

An analysis of the dependence of the flow of material from the angle of a wall openings and ethmoid plate thickness h is established that the minimum flow coefficient Kv is 0,33-0,47 material at angles of inclination of the side walls of the holes equal to 25-36 and the slab thickness equal 0.12-0.16 m openings for a rectangular shape.
   Holes in the ethmoid plate, made in the form of circular and elliptical shapes are not places of stress concentration, more high-tech in the manufacture of panels, but at a rate significantly lower than the amount of material with holes square and rectangular shapes. Square and rectangular holes forms contribute to the stress concentration at the corners of openings, which greatly reduces the life of grid plates precast foundation.
   To eliminate the stress concentration at the corners of the square and rectangular holes forms usually produce their conjugation. For further studies we will base precast grid plate with a rectangular shape aperture provided with a radiused and R r, equal to half the width of the openings (Fig. 2) on the upper and lower surfaces of the plate thickness h and the angle of inclination of the side walls of the hole a. Volume holes in a grid plate can be expressed as the sum of the volumes of geometric shapes: two truncated half cone (1) and the trapezoidal prism (2).
   On the lattice structure of precast slab foundation rigid pavement affected by the following parameters: slab thickness, size and angle of the side walls of the holes, their number and location in terms of the plate. Thus, the void ratio of prefabricated lattice slab foundation, one of the criteria in the design, can be represented as a function of several variables:
   KP = f (h, a, R, n, L), (8)
   where h - the thickness of the ethmoid plate; a - angle of the walls of the hole; R - radius of the bottom of the hole; n - the number of holes in a grid plate; L - length of the base of the prism.
   Theoretical study of the function (8) and its mathematical description are quite challenging taking into account all factors affecting the void ratio of the ethmoid plate precast base pavement.
   In assessing the influence of factors on the value of void ratio ethmoid plate precast foundation used a statistical method of experiment planning.
   Choice of numerical values ​​of the upper and lower levels of variation of the independent variables (see table) is made on the basis of theoretical and laboratory studies, as well as on the basis of the design features of the ethmoid plate.
   A numerical experiment was carried out in accordance with the D-optimal three-level composite plan B5, which is the basic condition for the absence of repeated combinations in rows and columns.
   To be continued.