Construction of a highway in the reserve area of the city of Al Ain in the UAE

The work was performed in accordance with the Supplementary Agreement No. 2 dated 24.08.08 to the Contract No. 02/2008 0t 08.02.2008. 

I. Source data. 

I. 1. The length of the highway is 1500 meters, width – 2.9 m.
The thickness of the hard coating is 0.2 m without a layer of wear. 
The axle load is 10 tons. 
Traffic intensity – 150 cars/day. 

I. 2. Terrain at the construction site-Fig. 1,2. Desert, with slightly intersected terrain. 

I. 3. Ground of the roadbed - sandy loam gravelly dusty, laboratory index- "G". 

I. 4. For the hard surface, a mixture of soil " G "with gravelly sand will be used, laboratory index- "O". 

I. 5. Characteristics of soils "G" and "O" are given in Table 1. 

Table 1. 

Name	Designation	Ground "G"	Ground "O"	Mixture of 50%G+ 0%O
Yield point \ ground, %	WT	17,5;	-	-
Ground rolling limit,%.	WP	13,5	-	-
Plasticity number	IP	4,0	0	2,0
Optimal soil humidity, %	Wopt	8,5	6,0	7,25
Soil density at Wopt, g / cm3	рopt	2,01	2,173	2,0915
Soil skeleton density  at Wopt, g / cm3	rsk, opt	1,85	2,05	1,95
Bulk material density air-dry soil, g / cm3	rnas	1,586	1,783	1,685
Skeleton density air-dry soil, g / cm3	rsk	1,575	1,77	1,67
Degree of heterogeneity  of the particle size distribution	Si	5,5	10,0	7,75
Soil classification	-	gravelly powdery  sandy loam	the sand is gravelly	-

I. 6. Physical and mechanical characteristics of the soils and mixtures used are given in Table 2. 

Table 2 - > 

I. 7. For the first experimental section, the thickness of the hard coating is assumed to be 0.2 m. 

I. 8. Material consumption per 1 m2 of hard surface and for the entire site – 1500 meters... 

Name of the material	Hard road surface, h=20 cm	By 1500 sq / m of road or 1500x2. 9=4350m2
Ground "G" (dry)	186.6 kg	811,626 kg
Ground "O" (dry)	186.6 kg	811,626 kg
Cement (dry)	15.6 kg	67,860 kg
Dorzin	0.006167 l	26.825 l

I. 9. Water consumption depending on the initial humidity of the mixture (Fig. 4). 

II. Updated technology. 

There can be many technology options, depending on the availability of various types of road construction equipment. 
Below is a variant of the technology with the use of a recycler, a motor grader, 2 rollers on pneumatic tires, 3 irrigation machines, and a cement distributor. A set of necessary equipment is shown in Fig. 5,6,7,8,9,10. 

Fig. 5-a recycler with a loosening drum located between the axles of the wheels. 

Fig. 6, Fig. 6-1 – a recycler with a rear location of the loosening drum. 
For the construction of hard surfaces, the recyclers Fig. 6 and Fig. 6-1 are most preferred. 

Figure 6-2-the recycling drum must be equipped with teeth for crushing solid materials!!! 
The recycler must be equipped with a water supply system to the loosening area (a flow meter and a distribution manifold in the cavity of the loosening drum), as well as a coupling for connecting the Dorzin water solution supply hose from the irrigation machine. 

Figure 7-motor grader. 

Fig. 8-roller on pneumatic tires. 

Fig. 9-irrigation machine with a capacity of 15-20 m3. 3-and machines. The machines must be equipped with a pump for feeding an aqueous solution of Dorzin to the collector-distributor of the recycler. It is completed with a hose and a connecting coupling for connection to the collector of the recycler. One of the machines must also be equipped with a pressure manifold Figure 9-1. 

Fig. 10-cement distributor. 

Figure 10-1-filling the cement dispenser from a cement truck. 

II.1. On the ground, along the entire length (1500 meters) of the planned route of the future road, the grader performs planning (Fig.7). Mounds are cut to a width of 2.9 m +1.0 m =3.9 m. 

II.2.To a depth of 0.15 meters, along the entire length of the planned road (1500 m), to a width of 2.9 meters, a recycler (Fig.5 or Fig. 6), symmetrical to the axis of the road, loosens the soil. 

II.3. Using a motor grader, the upper part of the loosened soil is removed to the width of the road (2.9 m) so that a "trough" with a depth of 5 cm is formed (Fig. 11). 

From the bottom of the trough, all stones with a diameter greater than 30 mm are selected manually and with hand tools (rakes).!!! 

II.4. In the trough for the entire length of the road, the soil "O" is delivered and distributed by a motor grader along the width of the roadbed – 2.9 m. Soil consumption "O" - according to the Table P. I. 8. 

II.5.Cement is applied to the entire surface of the planned ground "O" from a cement distributor (Fig. 10). Cement consumption is calculated according to Table p. I. 8. 

II.6. The recycler mixes the entire layer " pie " along the entire length and width of the road to a depth of 0.15 meters from the mark . 

II.7. The moisture meter determines the moisture content of the mixture made in accordance with paragraph II. 6. 

II. 8. Calculate the amount of water for the preparation of Dorzin solution per m2 of road surface. 

Amount of water added in liters per 1 m2 of road surface - Vvody: 

Wopt=7.45% - optimal ramming humidity of the mixture, taken from Table 2, 
Wcmixi-humidity of the mixture after mixing,
Dry mix = 388.8 kg – the weight of the dry mix from table P. I. 8 

The approximate amount of water is determined by Fig. 4. 

The Dorzin concentration in the solution is calculated. 

C = Vd/Vvodes , 

where: 
- C - Dorzin concentration (l\l); 
- Vd – Dorzin consumption per 1 m2 of road (Table p. I. 8); 
- Vwaters – water consumption per 1 m2 of road (Table p. I. 8). 

II. 9. A section of road to uqatka is planned - along the length, based on the volume of refueling of the irrigation machine, but no more than 100-200 linear meters in length (longer sections will lead to uneven distribution of humidity due to evaporation). Estimated amount (according to the C concentration calculated above) Dorzina is added to the container of the irrigation machine with thorough mixing. 

II. 10. The washing machine is placed in front of the recycler on a rigid hitch. The hydraulic tank of the irrigation machine is connected through a pumping system to the collector of the loosening drum of the recycler. 

All the prepared solution from the irrigation machine is applied together with the loosening of the recycler to the intended site. 

It is recommended to increase the estimated required amount of water by 20% on a hot day for subsequent evaporation. If the entire solution of the enzyme preparation has already been applied, and the soil moisture is insufficient, you can continue to apply a weak solution of 1: 10000. 

For example: if the initial humidity of the mixture is 1%, then the estimated amount of Dorzin solution for refueling 15 tons and a coating width of 2.9 meters is enough for-15000l ? [(7.45%-1%) x388, 8/100 x2, 9] =206 meters, but on these 206 meters it is necessary to add not 15,000 liters of Dorzin solution on a hot day, but 20% more, i.e. – 18,000 liters. Increase the amount of solution with water without increasing the amount of Dorzin! 

The flow rate of Dorzin solution is controlled by the recycler flow meter and is set depending on the speed of movement using the formula: 

If an excessive amount of water is added, then continue mixing the soil without adding water, until the required optimal humidity is reached; 

II. 11. The motor grader forms a cover profile. 

II. 12. The mixture is rolled up. 

II. 13. After 1-2 passes, the motor grader corrects the surface of the coating. 

II.14. When the surface of the coating dries out, the surface is additionally wetted with an aqueous solution of Dorzin 1: 10000 from a watering machine with a collector (Fig. 

The controlled coating parameter is a density of 2.1 g / cm3. The number of passes of the roller depends on the achievement of this density. 

II. 15. A roadside is formed 

The road IS READY, 

Have a nice trip! 

List of equipment: 

1. A recycler, the width of the loosening drum is -2.9 m, with a flow meter and a distribution manifold in the cavity of the loosening drum, as well as a coupling for connecting the hose for feeding the Dorzin water solution from the irrigation machine. 

Desirable recycler with a rear location 
of the loosening drum - 1 pc.; 

2. Motor grader - 1 pc; 

3. Pneumatic roller - 2 pcs; 

4. Water washing machine with a capacity of 15-20 tons with a pump and a hose for feeding the solution to the recycler, including one with a collector - 3 pcs.; 

6. Cement distributor - 1 pc; 

7. Moisture meter - 1 pc; 

9. Density meter - 1 pc. 

Before the arrival of specialists of the author's supervision, it is necessary to perform works at the road construction site, ending with item II. 4 of the technology!