Abstract: This paper aims to demonstrate how various algorithms can be implemented within swarms of autonomous robots to provide continuous inspection within underground pipeline networks. Current methods of fault detection within pipes are costly, time consuming and inefficient. As such, solutions tend toward a more reactive approach, repairing faults, as opposed to proactively seeking leaks and blockages. The paper presents an efficient inspection method, showing that autonomous swarm robotics is a viable way of monitoring underground infrastructure. Tailored adaptations of various Vehicle Routing Problems (VRP) and path-planning algorithms provide a customised inspection procedure for complicated networks of underground pipes. The performance of multiple algorithms is compared to determine their effectiveness and feasibility. Notable inspirations come from ant colonies and stigmergy, graph theory, the k-Chinese Postman Problem ( -CPP) and traffic theory. Unlike most swarm behaviours which rely on fast communication between agents, underground pipe networks are a highly challenging communication environment with extremely limited communication ranges. This is due to the extreme variability in the pipe conditions and relatively high attenuation of acoustic and radio waves with which robots would usually communicate. This paper illustrates how to optimise the inspection process and how to increase the frequency with which the robots pass each other, without compromising the routes they are able to take to cover the whole network.
Abstract: Dynamic traffic loads cause deformation of underground pipes, resulting in vehicle discomfort. This makes it necessary to reinforce the layers of soil above underground pipes. In this study, the subbase layer was reinforced. Finite element software (PLAXIS 3D) was used to in the simulation, which includes geocell reinforcement, vehicle loading, soil layers and Glass Fiber Reinforced Plastic (GRP) pipe. Geocell reinforcement was modeled using a geogrid element, which was defined as a slender structure element that has the ability to withstand axial stresses but not to resist bending. Geogrids cannot withstand compression but they can withstand tensile forces. Comparisons have been made between the numerical models and experimental works, and a good agreement was obtained. Using the mathematical model, the performance of three different pipes of diameter 600 mm, 800 mm, and 1000 mm, and three different vehicular speeds of 20 km/h, 40 km/h, and 60 km/h, was examined to determine their impact on surface settlement and vertical pressure at the pipe crown for two cases: with and without geocell reinforcement. The results showed that, for a pipe diameter of 600 mm under geocell reinforcement, surface settlement decreases by 94 % when the speed of the vehicle is 20 km/h and by 98% when the speed of the vehicle is 60 km/h. Vertical pressure decreases by 81 % when the diameter of the pipe is 600 mm, while the value decreases to 58 % for a pipe with diameter 1000 mm. The results show that geocell reinforcement causes a significant and positive reduction in surface settlement and vertical stress above the pipe crown, leading to an increase in pipe safety.
Abstract: Expanded polystyrene (EPS) geofoam is often used in below ground applications in geotechnical engineering. A most recent configuration system implemented in roadways to protect lifelines such as buried pipes, electrical cables and culvert systems could be consisted of two EPS geofoam blocks, “posts” placed on each side of the structure, an EPS block capping, “beam” put atop two posts, and soil cover on the beam. In this configuration, a rectangular void space will be built atop the lifeline. EPS blocks will stand all the imposed vertical forces due to their strength and deformability, thus the lifeline will experience no vertical stress. The present paper describes the results of a numerical study on the post and beam configuration subjected to the static loading. Three-dimensional finite element analysis using ABAQUS software is carried out to investigate the effect of different parameters such as beam thickness, soil thickness over the beam, post height to width ratio, EPS density, and free span between two posts, on the stress distribution and the deflection of the beam. The results show favorable performance of EPS geofoam for protecting sensitive infrastructures.
Abstract: The work aims to develop a robot in the form of
autonomous vehicle to detect, inspection and mapping of
underground pipelines through the ATmega328 Arduino platform.
Hardware prototyping is very similar to C / C ++ language that
facilitates its use in robotics open source, resembles PLC used in
large industrial processes. The robot will traverse the surface
independently of direct human action, in order to automate the
process of detecting buried pipes, guided by electromagnetic
induction. The induction comes from coils that send the signal to the
Arduino microcontroller contained in that will make the difference in
intensity and the treatment of the information, and then this
determines actions to electrical components such as relays and
motors, allowing the prototype to move on the surface and getting the
necessary information. This change of direction is performed by a
stepper motor with a servo motor. The robot was developed by
electrical and electronic assemblies that allowed test your application.
The assembly is made up of metal detector coils, circuit boards and
microprocessor, which interconnected circuits previously developed
can determine, process control and mechanical actions for a robot
(autonomous car) that will make the detection and mapping of buried
pipelines plates. This type of prototype can prevent and identifies
possible landslides and they can prevent the buried pipelines suffer an
external pressure on the walls with the possibility of oil leakage and
thus pollute the environment.
Abstract: Considering the numerous applications of the study of
the flow due to leakage in a buried pipe
in unsaturated porous media, finding a proper model to explain the
influence of the effective factors is of great importance.There are
various important factors involved in this type of flow such as: pipe
leakage size and location, burial depth, the degree of the saturation of
the surrounding porous medium, characteristics of the porous
medium, fluid type and pressure of the upstream.In this study, the
flow through unsaturated porous media due to leakage of a buried
pipe for up and down leakage location is studied experimentally and
numerically and their results are compared. Study results show that
Darcy equation together with BCM method (for calculating the
relative permeability) have suitable ability for predicting the flow due
to leakage of buried pipes in unsaturated porous media.