Vladimir Orlov

The Selection of Priority Pipe Sections for Sewer Network Renovation

Operative and planned rehabilitation of old pipe networks, including water disposal systems, is a relevant objective of modern city. It is especially difficult to make pipeline reconstruction works in large cities with high construction area density, transport moving intensity, also full of multifunctional both underground and above-ground infrastructure. All these factors set a lot of restrictions for open excavation methods of pipelines repair and reconstruction. That is the reason why trenchless technologies are becoming more popular among the engineers. A wide range of trenchless techniques provides people with convenient method of fast and effective reconstruction processes in comparison with durable and inconvenient open excavation. This fact leads to a necessity of creating a strategic planning of pipeline rehabilitation. This article presents how to operate the first step of such strategic planning – choosing the priority pipe section for sewer network renovation. The most convenient way for choosing one specific section from a great range is to use a program package based on mathematical algorithm that takes into account a quantity of different factors. This paper presents such a program created by authors and describes its interface, date input and processing.

Choosing an Optimal Trenchless Renovation Method for Pressure and Non-Pressure Pipes

The paper presents the innovative decision of the problem of choosing the most effective pipe renovation method among the wide range of them. To solve this problem a computer program called “Repair 2012” was developed. The factors influencing the selection process of optimal renovation method for pressure and non-pressure pipes and the theoretical base for creating a computer program are described. The program algorithm based on weighted analysis of these factors. Weighting coefficients for each factor are calculated using arithmetical mean for all concerning trenchless methods. The income and outcome user information, the sequence of the process of working with the program are represented in the article. The process and results on determining an optimal renovation method are shown as an example.

Analysis of the Strength Characteristics of Internal Sprayed Protective Coatings of Pipelines to Improve Energy Efficiency

The most part the RF pipelines require renovation because of their unsatisfactory state. Besides, the pipelines under operation are subject to biological fouling and at the result reduction of the living cross-section of pipes and increase of the hydraulic resistance and improve energy efficiency. One of the methods, which helps to prevent this situation, is application of a sprayed coating to the inner part of a pipeline. Due to many available market proposals, provision has been made of a complex of bench tests aimed at studying strength characteristics and computer simulation of two types of protective coatings to reveal their modifications during a period of time, i.e. Scotchkote 2400 («3M» Company), which is the most popular one and Subcote FLP, which is a prospective development by the NPP “Polyplastic”. Testing has been made at the electromechanical tensile testing machine Instron 3345 and simulation by the «Ansys» automated computer ware of the finite element analysis. The results of the performed tests permitted to determine the recommended coating thickness depending on the pipeline diameter.

Trenchless Technology Application of Protective Coatings That Provide Energy Savings Associated with Transport of Water via Pipelines

The article presents the analysis of trenchless technologies and different types of inner protective coatings of the pipelines, which may be used as the repairing materials to enable the power saving effect during the water transport. As the protective coatings the article examines round and deformed profile pipes, sprayed coatings on the base of non-organic and organic materials. The notion of a power saving potential has been formulated, when the protective coatings are used for trenchless repairing works of water supply pressure pipelines, as well as the methods of its calculation per running meter of a pipeline length per year. The Swagelining power effective technology was subject to a complex examination on the basis of the created automated software. There is presentation of the algorithm for calculation of some geometrical and power parameters, in particular, the wall thickness of a polyethylene pipe to be pulled after its compressing and straightening into the old pipeline, as well as the dynamical changes of the pressure losses before and after the renovation works in the pipeline by the Swagelining technology, when SDR are taken within a wide range of limits determining the ratio of the pipe diameter to its wall thickness. The data, which have been got at the result of the automated calculation, show that during renovation of old pipelines by the Swagelining technology the required effect may be got both from the technical point of view (complete restoration of the old pipeline part by elimination of damaged points) and the economical one due to a great power saving effect.