Product(s):	SewerGEMS, SewerCAD, StormCAD, CivilStorm
Version(s):	CONNECT Edition Update 1 and greater
Area:	Output & Reporting

Overview

This Technote explains how to use the Engineering Standards feature, to supplement the Help documentation.

The Engineering Standards feature is available starting with the CONNECT Edition Update 1 version of Bentley’s Storm and Sewer products.

Note: for WaterCAD and WaterGEMS, see Alerts and Alarms

Demonstration

Watch this two-minute video for a quick demonstration:

https://youtu.be/XFp-NJ0YiWo

What are Engineering Standards?

The Engineering Standards are a set of parameters which can be taken for validation as per your design requirements, for physical/input parameters (not computed results). Often while designing a storm conveyance system or a sewerage system there are certain standards that are enforced by the local governing body which need to be fulfilled or certain good practices which you follow for your design. In other cases, there are situations when certain limitations might be enforced; for example, a specific range of diameters to be used or a specific material must be used. All these conditions which may be project specific or might come under standards that need to be followed can be used in this tool which will help you identify your model accuracy as per the Engineering Standards defined. This feature enables you to customize validation rules for your model to be checked against a set of specific engineering standards, such as diameter ranges, materials, and pump status. You can also define the severity of the standard (Information, Warning, Error). If flagged during validation, this will appear in the Engineering Standards tab next to User Notifications. This way, a hydraulic model reviewer can quickly review any design standard violations and can apply these standards across multiple models.

In this feature you must first define custom validation rules to be used to check your model. As with regular User Notifications there are different types of validation messages viz. Information, Warning and Error which can be defined as per your requirements. This customization of severity of validation depends on the engineering standards employed. For example, if an engineering standard has been defined to check pipes within a specific diameter range; whichever diameter that falls beyond this range would be flagged during validation as a “Warning”. This means that the hydraulic calculation will be performed for this pipe diameter but it will give out a warning indicating that the diameter is beyond the specified engineering standard. However, if an Engineering Standard is setup as an “Error” it would show up as a red “error” notification but it does not indicate invalid results or a failed run. An “Error” while validation of Engineering Standards is merely a notification generated by a standard defined by the user whereas an “Error” in User Notification is flagged when the software finds errors during analysis of the model.

To understand more about the severity values required to be set this article outlines the different user notifications during validation, their significance and impact on hydraulic design. It is to be noted that the engineering validation messages which appear with the Validate command, not with Compute.

The validation flags will appear under a separate tab next to User Notifications named simply as Engineering Standards.

Note:

Engineering Standards only apply to input fields, not results (calculated fields)
Engineering Standards are customized rules for validation of the hydraulic model and are generated only when the “Validate” within the Engineering Standards dialog box is clicked and not the “Validate” button next to “Compute” under the Analysis Tab.

As seen above, a “Warning” is issued by the software during validation which tells you that there is a violation of the engineering standard set.

Defining Engineering Standards

The Engineering Standards feature can be found in the Calculation tab under the Home tab.

Creating Engineering Standards involves creating logical rules or statements and assigning a Severity Value (Information, Warning & Error) as per your requirement. Upon clicking the Engineering Standards tool, a dialog box opens which has fields within which you can define the standard.

The following fields are available when defining your standards;

Enable	:	Specify whether this standard must be used or not. This is useful if you have multiple standards specified but wish to check only for specific standards.

Label	:	Specify the standard name (E.g. Diameter Standard)

Severity	:	Define the severity value as Information, Warning and Error as per your requirement. By default, “Error” would be set.

Element Type	:	Specify the element type from the drop-down menu (E.g. Conduit, Manhole etc.)

Include Elements	:	Here you have the option to specify which elements to validate under the respective engineering standard. By default, all elements (entire model) is selected.

Field	:	Define the property which you want to validate as an Engineering Standard (E.g. Diameter, Material etc.)

Test Criterion	:	Define the testing condition for your parameter. This field can be populated using the standard logical operators available viz. <, >, <>, =, >=, <= and Range. The range test criterion is useful to define a range of values.

Value	:	Define your test value. (E.g. Material = PVC). In this case any conduit material other than PVC would be flagged and appear under Engineering Standards tab during validation.

		Note: The test value field would be yellow (un-editable) if “Range” is selected as the test criterion.

Min	:	This field is by default in yellow (read only), but activates when “Range” test criterion is selected to define your standard. Here you can specify the minimum value of your range.

Max	:	Same as Min field. Here you can specify the maximum value of your range.

Creating Engineering Standards

In this section we will create some examples which will help you understand how Engineering Standards work.

Creating an Engineering Standard for Diameter

Often while designing a new hydraulic network there are project constraints on the pipe sizes available for use. Generally, only a few pipe sizes within a range are used in hydraulic analysis. In this example there is a simple hydraulic model created in SewerGEMS where the conduit diameters are ranging from 200 mm to 300 mm. We will create an engineering standard which validates and gives a warning if the conduit diameter is not within range (200 mm to 300 mm).

For the simple network shown above, the following engineering standard is created;

Enable	:	True (checked)

Label	:	Diameter Standard

Severity	:	Warning

Element Type	:	Conduit

Include Elements	:	<All Elements>

Field	:	Diameter (mm)

Test Criterion	:	Range

Value	:	-NA- (this field is yellow since “Range” is the test criterion)

Min	:	200

Max	:	300

When the above parameters are defined, the Engineering Standards would look like this;

After the engineering standard is successfully defined the validate command should be used to evaluate and list any relevant engineering validation messages. The Validate command may also surface notifications in the normal User Notifications tab as well, some of which may be related to the Design Constraints.

Note:
The engineering standards are independent of the user notifications created. The user notifications are created based on the software’s internal thresholds and the criteria specified in the Design Constraints. In the Design Constraints tool found in the Analysis Tools under the Analysis tab you can specify the basic design parameters within which you wish to analyze your model. These design criteria are defined for a model which are checked for violations if the results are beyond the prescribed ranges. This won’t stop the model from computing as these are “Warnings” provided to the User. Any violation of these parameters would show up in the User Notifications tab.

The engineering standards alerts on the other hand will show up in the Engineering Standards tab next to User Notifications.

Upon Validation of the model, User Notifications will appear, or you will see “No Validation issues found”.

After Validation checks for normal model validation issues, the following message will appear if there is a violation of the engineering standards that you have specified.

The following is an example of a possible Engineering Validation violation notification.

The above notification is of the “warning” type and acts as an alert that conduit CO-8 has a diameter (900 mm) beyond the standard range of 200-300 mm. If you double-click on the notification, the related element is selected in the drawing pane.

Creating an Engineering Standard for Material

For this example, we will work within the same model and check for the material of the conduit. Here we shall check the example based on certain search conditions with the include elements option. We want all pipes with diameters above 200 mm to have their material set as “Ductile Iron”.

To create a criterion based on specific elements to be included in the engineering standard we have to develop a query. The ellipsis within the “Include Elements” field opens the Query Builder tool. This article explains how queries can be built to return desired values. For our example the query can be created by selecting the diameter property from the available fields. Using the “>” operator and available unique values our query would look like this;

Thus, the following Engineering Standard is created;

Enable	:	True (checked)

Label	:	Material Standard

Severity	:	Warning

Element Type	:	Conduit

Include Elements	:	ConduitDiameter > 200

Field	:	Material

Test Criterion	:	=

Value	:	Concrete (clicking the ellipsis button will populate all material values)

Min	:	-NA- (this field is yellowed since we are not using the “Range” criterion)

Max	:	-NA- (this field is yellowed since we are not using the “Range” criterion)

When the above parameters are defined, the Engineering Standards would look like this;

It can be seen from the above image that we now have two engineering standards created (one for diameter, other for material). At this point the User has the option of selecting which engineering standard to validate by checking/unchecking the “Enable” field for that standard. The software provides this additional functionality to the User by providing the option to choose which engineering standards to validate. For this case we will keep both the engineering standards active for validation.

Upon validation of the model the Engineering Standards tab will look like this;

We see here there are two violations of the engineering standards specified (diameter and material) which show up in the Engineering Standards Tab.

From the above notification we can see that the notification is of a “Warning” type. The message says that “Material (Ductile Iron) must be Concrete”. By specifying the engineering standard to check for material, the program has returned that conduit (CO-6) is having material as “Ductile Iron” which is not the specified material (Concrete) prescribed in the engineering standard. If you double-click on the notification, the element in concern is selected in the drawing space.

In this way you can create engineering standards for all the properties associated with your network elements and check the suitability of the model based on your defined criteria.

Engineering Standards v/s Design Constraints

The major difference between Design Constraints (used with the constraint based design feature) and Engineering Standards is that, engineering standards are used to validate the model for good engineering practices or some other test criteria which is not already represented in the Design Constraints.

For example, the velocity range for a model is specified as 0.6 m/s to 3 m/s in the Design Constraints. However, a good engineering practice or field observation shows that conduits have greater life if the velocity is within the range of 0.75 m/s to 2.5 m/s. Now for this case, the standard values for which the entire network needs to be designed are 0.6 m/s to 3 m/s which must be maintained to design the network. So, for this case we will create an engineering standard which shows us all the conduits which are having velocity within 0.75 m/s to 2.5 m/s as a measure of the field observation data related to pipe longevity. For this case it is unwise to change the Design Constraints to our field data values, since it is an observational data and not standard values. Also, it will unnecessarily stress the entire network to more stringent parameters than required which would not be the most optimal solution. Ideally a solution should balance all the specified design criteria equally.

Import / Export Functionality

Engineering Standards once created can be used multiple times for other projects and hydraulic models by exporting them using the “Export” button and saving them for future. The engineering standards are saved with the file extension of .dstx. For a new project you can directly import the previously created standards simply by clicking on the “Import” button and browsing to the location of saved engineering standards file.
The import and export options are available next to the validate option in the Engineering Standards dialog box.

Using Engineering Standards