ANALYSIS OF THE CURRENT STATE OF ROAD SURFACE DRAINAGE
Saidakhror Orifjonov
Tashkent State Transport University
ABSTRACT
The main reason for the deterioration of the state of the road, as well as its premature destruction of the pavement, is water. Today in our country, the main source of waterlogging of the body of the subgrade is rainwater. During heavy rains, part of the water flows over the surface of the earth, while the other part seeps through cracks in the road surface into the body of the subgrade, increasing moisture and reducing the bearing capacity of the soil.
Keywords: drainage, surface water, surface drainage, inlet, gutter.
INTRODUCTION
Removal and drainage of surface water from the road and adjacent land is known as surface drainage [1].
The term "drainage" is defined as the interception and removal of water from, above and below the surface. Hence, road drainage is the process of removing excess water from the road surface as well as from the roadbed.
Road drainage is an integral part of its design and construction, where the process of removing excess water takes place within the boundaries of the road. Drainage of highways occurs mainly due to surface runoff from the adjacent territory after atmospheric precipitation.
Surface drainage
It is a type of drainage system in which the road surface water is collected and discharged into the road's right-of-way. Surface drainage is mainly designed to prevent surface water from entering the shoulders, subgrade or any other layer of the road surface [2].
In surface drainage, we must take into account the frequency of floods, the capacity of drainage structures such as pipes and channels, side ditches, cross slopes and slopes, gutters, longitudinal slopes, etc. [1].
Water drainage using side channels or gutters
The simplest and oldest drainage method is the construction of side channels. Side gutters are usually constructed parallel to the roadside to efficiently drain surface water.
The figure below shows a cross-sectional view of a side gutters in an embankment designed for proper surface drainage. The section of the side gutter is, as a
rule, trapezoidal, but side gutters of a triangular shape are also provided in the recess [2].
Pavement
Fig. 1. Pavement drainage with side ditches
These were the simplest methods of surface drainage.
Water drainage using inlets or catch basins
And also, in practice there is the use of inlets for more efficient removal of water from the surface of highways.
A storm water inlet is a drainage structure consisting of a rectangular and cylindrical well, gratings and pipes. Below is a pictorial drawing of a storm water inlet shown.
Fig. 2. Horizontal inlet with grating
The main advantage of a such drainage system is that after rains or other sources of flooding, water is quickly removed from the roadway and does not interfere with the free movement of cars and pedestrians. But there is also a minus of a such system, which requires regular inspection and maintenance.
Literary analysis showed that in Western countries the use of this type of drainage is due to safety, aesthetics and, most importantly, efficiency.
REFERENCES
1. Study of Surface and Sub Surface Highway Drainage System. Tejas D. Khediya Lecturer in Civil Engineering Department Sir Bhavsinhji Polytechnic Institute-Bhavnagar-Gujarat, 2016.
2. www.civilengineeringnotes.com/Road Drainage System (Highway Engineering), 07/09/2020 by vicky.