Maintenance optimization system for water pipelines

A method of determining optimal repair options for cast iron and ductile iron water or wastewater pipe sections having a number of pipe-lengths, which have been inspected using a pipe wall thickness measurement device, the method comprises the computer-implemented steps of:

• (a) inputting measured pipe-length wall dimensional data, geometric and materials properties of the pipe-length, tool measurement errors, and analysis parameters;
• (b) determining pipe failure rates for current and future times based on the input data, by determining probability of pipe-length failure due to leaks through corrosion pits and determining probability of pipe-length failure due to transverse bending of a corroded pipe-length;
• (c) defining at least one repair scenario for the pipe section and determining pipe failure rates for the at least one defined repair scenario;
• and
• (d) providing the pipe failure rate determinations to the user as output information;
• wherein defining the at least one repair scenario includes allowing the user to define at least one repair option for at least one pipe-length;
• wherein, prior to the user defining the at least one repair scenario, the user is provided with a set of suggested repair options based on a predefined selection logic;
• and
• wherein the predefined selection logic compares an estimated average wall thickness of each pipe-length to a threshold average wall thickness amount to identify one or more repair options appropriate for the overall condition of the pipe-length.

A method of remodeling pipe-length wall thickness comprising:

• (a) representing, the wall thickness of the pipe-length as the thickness of the elements of a grid covering the surface of the pipe-length;
• and
• (b) assigning a probabilistic variable thickness to each element in the grid;
• wherein the size of the grid elements are determined by a radial extent of the worst corrosion pit and axial resolution of the tool.

A method of modeling pipe length wall thickness comprising:

• (a) representing the wall thickness of the pipe-length as the thickness of the elements of a grid covering the surface of the pipe-length;
• (b) assigning a probabilistic variable thickness to each element in the grid;
• and
• (c) supplying desired repair information and determining the effect of the repair on the pipe-length wall thickness by adjusting the parameters of the probabilistic variable wall thickness according to the repair information.

In a computer system having a graphical user interface including a display and a user interface selection device, a method comprising the steps of:

• (a) displaying a menu having selections of input pipe data, set pipe repair options, and display pipe output information;
• (b) receiving instruction from the user to input pipe data and in response inputting pipe wall dimensional data;
• (c) receiving instruction from the user to set pipe repair options and in response defining at least one repair scenario for the pipe section;
• (d) determining pipe failure rates for the at least one defined repair scenario, including determining pipe failure rates for current and future times based on the wall dimensional input data;
• and
• (e) receiving instruction from the user to output the pipe failure rates and in response displaying the pipe failure rates;
• wherein determining pipe failure rates includes determining probability of pipe failure due to leaks from pit perforation and determining probability of pipe failure due to transverse bending.

In a computer system having a graphical user interface including a display and a user interface selection device, a method comprising the steps of:

• (a) displaying a menu having selections of input pipe data, set pipe repair options, and display pipe output information;
• (b) receiving instruction from the user to input pipe data and in response inputting pipe wall dimensional data;
• (c) receiving instruction from the user to set pipe repair options and in response defining at least one repair scenario for the pipe section;
• (d) determining pipe failure rates for the at least one defined repair scenario, including determining pipe failure rates for current and future times based on the wall dimensional input data;
• and
• (e) receiving instruction from the user to output the pipe failure rates and in response displaying the pipe failure rates;
• wherein the repair scenario includes repair options of at least one of no action, pipe-length replacement auger anode protection, pit clamping, structural liner, and nonstructural liner;
• wherein, prior to allowing the user to define at least one repair scenario, the user is assisted in selecting repair options by providing the user with a set of suggested repair options based on a predefined selection logic;
• and
• wherein the predefined selection logic compares the measured remaining wall thickness and radial extent of the worst corrosion pit to threshold amounts to identify one or more repair options appropriate for the localized pitting in the pipe-length.

In a computer system having a graphical user interface including a display and a user interface selection device, a method comprising the steps of:

• (a) displaying a menu having selections of input pipe data, set pipe repair options, and display pipe output information;
• (b) receiving instruction from the user to input pipe data and in response inputting pipe wall dimensional data;
• (c) receiving instruction from the user to set pipe repair options and in response defining at least one repair scenario for the pipe section;
• (d) determining pipe failure rates for the at least one defined repair scenario, including determining pipe failure rates for current and future times based on the wall dimensional input data;
• and
• (e) receiving instruction from the user to output the pipe failure rates and in response displaying the pipe failure rates;
• wherein the repair scenario includes repair options of at least one of no action, pipe-length replacement, auger anode protection, pit clamping, structural liner, and nonstructural liner;
• wherein, prior to allowing the user to define at least one repair scenario, the user is assisted in selecting repair options by providing the user with a set of suggested repair options based on a predefined selection logic;
• and
• wherein the wall dimensional data includes an estimated average wall thickness and the predefined selection logic includes comparing the estimated average wall thickness with a threshold average wall thickness amount to identify one or more repair options appropriate for the overall condition of the pipe-length.

A method of modeling pipe-length wall thickness comprising:

• (a) representing the wall thickness of the pipe-length as the thickness of the elements of a grid covering the surface of the pipe-length;
• and
• (b) assigning a probabilistic variable thickness distribution to each element in the grid;
• wherein the thickness distribution includes a standard deviation calculated as a function of the probability of the wall being less than or equal to a minimum wall thickness.

A method of modeling pipe-length wall thickness comprising:

• (a) representing the wall thickness of the pipe-length as the thickness of the elements of a grid covering the surface of the pipe-length;
• and
• (b) assigning a probabilistic variable thickness distribution to each element in the grid;
• wherein the probabilistic wall thickness distribution is characterized by an average wall thickness and a minimum wall thickness;
• wherein the average wall thickness and minimum wall thickness are determined from actual measurements taken of the pipe length using an inspection device;
• wherein the probabilistic wall thickness distribution includes consideration of an inspection device measurement error;
• and
• wherein the consideration of an inspection device measurement error includes calculation of at least one of an average wall thickness measurement error parameter Cμ, a minimum wall thickness measurement error parameter Cmin, and a circumferential extent measurement error parameter Cθ.