Abstract

The development of Molecor´s technology, which is based on the application of a Molecular Orientation process, has delivered a significant turning point in the pipelines sector. With this technological development, the company has begun to manufacture TOM® PVC-O pipes, the most eco-friendly pipes on the market. The Molecor technology enabled eradicating many of the existing disadvantages of thermoplastic pipes. This technology delivers a clear objective; to provide the water industry with a solution for pipes carrying pressurized water in an environmentally friendly, yet cost efficient manner. This also extends a service life compared to pipeline materials currently in use. The Molecor´s technology has faced numerous barriers due to the high level of competitiveness in the market and the relatively short period since its development. Notwithstanding, the technology is now highly recognized by the market and has spread continuously and gradually over the world to the five continents. We have served many international markets: North America (i.e., Canada), South America (i.e., Colombia and Ecuador), European countries (i.e., Italy and Spain), African countries (i.e., South Africa) and East countries (i.e., India, Kazakhstan, Malaysia and Australia).

Abstract

In most gravity fed water transmission pipelines, it is desired to reduce excess pressure head to prevent undue strain on a pipeline and lower the incidence of leaks. Normally this is done with pressure reducing valves that essentially burn off this excess pressure as heat. The LucidPipe™ system converts it to low cost electricity thereby removing unwanted pressure and generating energy at the same time - energy that can be put used behind the grid or put back on the grid. The LucidPipe™ system extracts a small percentage of pressure head providing nearly invisible operation allowing water operators to fulfill their primary mission of delivering water to consumers. Because the LucidPipe™ system extracts only a small percentage of pressure head when operating, and about 1 psi of pressure head when stopped, it is virtually invisible in a pipe network and can be placed directly in-line without the need of a bypass for the turbine. Traditional hydropower turbines effectively halt the flow of water when stopped, and can cause dangerous water hammer when grid power is disconnected so they must be placed in a bypass to not interrupt the safe delivery of water. Also, traditional hydropower turbines operate in a narrow band of pressures and flows whereas the LucidPipe™ system has a wide operating range typically found in municipal water transmission system. The LucidPipe™ system adjusts to meet the demands of water delivery rather than a water operator having to adjust the water to meet the demands of the turbine.

Abstract

Caterpillar developed MDP (Machine Drive Power) technology to fill this gap. Rather than an accelerometer and vibratory drum, it uses the principle of rolling resistance to provide indications of soil stiffness. This allows it to perform more reliably on cohesive and granular soils with less variability than accelerometer systems. It also means that the technology can be used on both vibratory and static drum compactors, which are often used on larger sites. While the technology is quite useful on its own, it is even better as a complementary technology to the existing accelerometer-based systems. Contractors who use vibratory soil compactors equipped with MDP and accelerometer-based measurement systems enjoy the widest application range, able to ensure uniform, high quality compaction on nearly any soil type.

Abstract

Triax’s Spot-r system was developed to tackle the construction industry’s unique safety and productivity challenges, stemming from a demonstrated lack of total jobsite visibility and automatically collected, easily accessible field data. Spot-r by Triax combines a proprietary mesh network with sensor technology to record and transmit previously unattainable workforce and equipment location, activity and safety data within a defined area – all in real-time. The Spot-r network is installed around the site and operates in a 900 MHz network, with a subset using a cellular connection to forward Spot-r sensor data to Triax’s custom, cloud dashboard. In the hazardous construction environment, the wearable Spot-r Clip detects worker slips, trips, or falls on site and sends automatic alerts to designated personnel. Workers can also trigger an alert to supervisors via their wearable device. In a situation that requires an evacuation, superintendents can activate the Spot-r EvacTag, which augments current evacuation procedures with a visual, high-decibel alarm. Real-time worker headcounts and floor- and zone-based location via the Spot-r dashboard eliminates time spent tracking down people or information and helps account for workers during an evacuation. Operating off the same network and working with the Spot-r Clip, the Spot-r EquipTag adheres to nearly any piece of equipment to track real-time location, utilization, and operator identity, providing a comprehensive view of how resources are interacting on site. Aggregate utilization data by operator, subcontractor, zone, or time period helps coordinate resources and minimize downtime. By automatically collecting real-time data from workers and equipment - without technical limitations such as wireless internet, project scope, or clear line of sight to the sky - Spot-r provides unprecedented visibility into site operations and safety, helping contractors build safer and smarter. Spot-r is currently being used on more than 40 sites by some of the nation’s leading contractors, including Turner and Gilbane.

Abstract

The extra quantities of wastewater entering the pipes can cause backups that result in sanitary sewer overflows. Urban underground infrastructure monitoring is important for controlling the flow of extraneous water into the pipelines. By combining the wireless underground communications and sensor solutions, the urban underground IoT applications such as real time wastewater and storm water overflow monitoring can be developed. In this paper, the path loss analysis of wireless underground communications in urban underground IoT for wastewater monitoring has been presented. It has been shown that the communication range of up to 4 kilometers can be achieved from an underground transmitter when communicating through 10cm thick asphalt layer.

Abstract

This research introduces an inverse transient-based optimization approach to automatically detect potential faults, such as leaks, partial blockages, and distributed deteriorations, within pipelines or a water distribution network (WDN). The optimization approach is named the Pipeline Examination Ordinal Symbiotic Organism Search (PEOS). A modified steady hydraulic model considering the effects of pipe aging within a system is used to determine the steady nodal heads and piping flow rates. After applying a transient excitation, the transient behaviors in the system are analyzed using the method of characteristics (MOC). A preliminary screening mechanism is adopted to sift the initial organisms (solutions) to perform better to reduce most of the unnecessary calculations caused by incorrect solutions within the PEOS framework. Further, a symbiotic organism search (SOS) imitates symbiotic relationship strategies to move organisms toward the current optimal organism and eliminate the worst ones. Two experiments on leak and blockage detection in a single pipeline that have been presented in the literature were used to verify the applicability of the proposed approach. Two hypothetical WDNs, including a small-scale and large-scale system, were considered to validate the efficiency, accuracy, and robustness of the proposed approach. The simulation results indicated that the proposed approach obtained more reliable and efficient optimal results than other algorithms did. We believe the proposed fault detection approach is a promising technique in detecting faults in field applications. Document type: Article

Abstract

This article models a novel driving-day-based tradable credit scheme (DD-TCS) to alleviate urban traffic congestion. In this model, car-using allowances (in terms of the number of days in a month, termed as “credit”) are freely and uniformly allocated to all travellers, who are also allowed to trade them in a market according to his/her travel needs (e.g. driving more or fewer days than the free endowment). As opposed to most studies on TCS, this paper explicitly considers the transaction cost (e.g. information cost of finding potential traders) in the trading market. To assess the feasibility of DD-TCS, we compare it against the license plate rationing (LPR) scheme, which has been practically implemented in many cities such as Beijing and Chengdu in China. Taking the performance of LPR as a benchmark, we quantify the threshold values of the transaction cost in DD-TCS when the two schemes yield equivalent performance (in terms of the total generalized cost). In numerical studies, we also compare the DD-TCS and LPR with the no-action case and the congestion pricing case (representing the theoretical optimum). Results show that both DD-TCS and LPR outperform the no-action case under certain conditions. With small transaction cost, DD-TCS may achieve a lower system cost that can be very close to the ideal optimum. In addition, parameter analysis shows that DD-TCS performs better than LPR in a wide range of transaction cost, where the threshold values appear to account for a considerable portion of the auto travel time. This implies that DD-TCS will be more appealing than LPR in practice because a transaction cost lower than the extremely large threshold values can be easily achieved for the trading market, e.g. via a mobile platform and modern communication techniques. Document type: Article

Abstract

Air pockets generated during emptying operations in pressurized hydraulic systems cause significant pressure drops inside pipes. To avoid these sudden pressure changes, one of the most widely used methods involves the installation of air valves along the pipeline route. These elements allow air exchange between the exterior and the interior of the pipe, which alleviates the pressure drops produced and thus prevents possible breaks or failures in the structure of the installation. This study uses a mathematical model previously validated by the authors in smaller installations to simulate all hydraulic variables involved in emptying processes over time. The purpose of these simulations is the validation of the mathematical model in real large-scale installations, and to do this, the results obtained with the mathematical model are compared with actual measurements made by the partner company. The hydraulic system selected for the study is a pipeline with a nominal diameter of 400 mm and a total length of 1020 m. The results obtained from the mathematical model show great similarity with the experimental measurements, thus validating the model for emptying large pipes. Document type: Article

Abstract

Optimisation of water distribution system design is a well-established research field, which has been extremely productive since the end of the 1980s. Its primary focus is to minimise the cost of a proposed pipe network infrastructure. This paper reviews in a systematic manner articles published over the past three decades, which are relevant to the design of new water distribution systems, and the strengthening, expansion and rehabilitation of existing water distribution systems, inclusive of design timing, parameter uncertainty, water quality, and operational considerations. It identifies trends and limits in the field, and provides future research directions. Exclusively, this review paper also contains comprehensive information from over one hundred and twenty publications in a tabular form, including optimisation model formulations, solution methodologies used, and other important details. Document type: Article