Presentation on theme: "July 2010. Training Outline Part 1 Cost-per –SF and Detailed Estimate Pay Item Detailed Estimate Segments Bridge Level Data Segment Level Data Supports."— Presentation transcript:
Training Outline Part 1 Cost-per –SF and Detailed Estimate Pay Item Detailed Estimate Segments Bridge Level Data Segment Level Data Supports Part 2 Sketches Supporting Tables and Other Information
Cost-per-SF & Item Details Two methods are now available for estimating bridges: Cost-per-square foot (no change from previous) Pay item detailed You can choose to use either or both:
Primary Bridge Estimate If you choose to have both a cost-per-square foot and a detailed estimate, you must designate one as the Primary: For reporting and review (similar to Primary Version designation); Not limited to LRE Coordinators; Can be changed at any time (if the project is not in Blocked status).
Cost-per-Square Foot Method The cost-per-square foot method will remain the same as it was previously. Screen is the same, except the fields for Superstructure and Substructure types have been removed. For projects that had bridges prior to the implementation of the detailed component, the implementation did not affect (or change) the existing costs-per-square foot.
The remainder of this presentation will apply to the Pay Item Detailed method of estimating bridges...
Designed for common bridge types (the 90%) Pay item detailed component is not intended for estimating specialty bridges Specialty bridges can be estimated by the cost-per- square foot method, or as X-Items. Pay Item Detailed Method SuperstructuresSubstructuresFoundations FL I-BeamPile BentsPrestressed Square Piles (18 & 24) FL U-BeamDrilled Shaft BentsDrilled Shafts (48 & 60) Slab (Cast in Place)Multi ColumnSteel Piling (14 x 89 and 14 x 117) Steel BoxHammerhead Steel Plate Girder
Bridge Segments Bridges that have varying types (or heights) can be separated into Segments for more accurate estimating. A bridge can have one Segment, or many. For each segment: Superstructure, Substructure and Foundation types are selected from a list.
First and Last Segments When you initiate a detailed estimate, the system assumes there is one segment. The first segment created is automatically designated as the First and Last segment: End Bents are automatically added to the segments designated as First and Last.
Bridge Segments If multiple segments are created, you must designate First and Last Segments so that end bent quantities will be appropriately generated:
Bridge Segments Example of a bridge requiring multiple segments for variations in height:
Bridge Level and Segment Level Data Data that remains consistent through all segments is input on the Bridge Level screen. Bridge level data relates primarily to the type of construction and the characteristics of the bridge deck (typical section, railings, etc.). Data that changes between segments is input on the Segment Level screen. Segment Level data relates primarily to dimensions, and types for superstructure, substructure and foundation.
Bridge Level Data User Input / Selection: Bridge Typical Section Construction Type Average Skew Angle Sidewalk Widths Railings, Left & Right Traffic Separator Width Generated Values: Total Cost and Cost/SF Approach Slabs Total Length and Average Width (from Segments) Quantities for Displayed Pay items
New Bridge Defaults When you create a new bridge a single segment is created, with default measurements and characteristics. The Bridge Level Detail screen will display the Initial Segment Default values. These values will not be accurate for your bridge; They are there because LRE must have a starting point; You can change them here or on the Segment Details screen.
Segment Level Data User Input, per Segment: Segment Dimensions & Clearance Over Land or Water Number of Intermediate Supports Superstructure, Substructure, Foundation Types (selected) Calculated Values: Average Pile Length Span Length Quantities for all related pay items
Segments & Intermediate Supports The Number of Intermediate Supports is an input value on the segment, estimated by the coder. There will be a default value for the first segment, based on total bridge length and other factors (bridge loads, etc.). The default value can be changed. If additional segments are created, there will not be a default number of intermediate supports. The number will have to be estimated by the coder and manually entered. This value has a significant impact on the quantities calculated!
Example of Segments and Supports The example bridge below has been separated into 3 segments, for differing heights; Intermediate Support numbers, per segment are: Segment 1 = 0, Segment 2 = 2, Segment 3 = 0 Dont count end bents! (Automatically included.) The program automatically adds the quantities for this pier into Segment 3 The program automatically adds the quantities for this pier into Segment 2 These piers are counted as input values in Segment 2
Bridge Optional Tab This tab contains input fields for several items that are commonly used on bridge projects, but do not have generated quantities. Removal of Existing Structures Sheet piling Protection of Existing Structures Navigation Lights, Fender System, Fiberglass Piles Slope Protection Expansion Joints Takes the place of X-Items for these items. Quantities must be included, but prices will be generated.
Bridge Widening Rules The program requires that one of the widening types shown here be selected. If the specific widening type falls outside of these options, the estimate should be based on the square foot cost or by using X-items.
Bridge Widening Rules Widening Two Sides- The program is set up for widening on one side of the bridge. If the project requires widening on both sides, run as separate bridges and sum the quantities. Match Existing - In general, the superstructure type of the bridge widening should always match the existing.
Hammerhead Piers Hammerhead Piers come in different shapes
Hammerhead Pier Options For high-level water crossings, two hammerhead piers set side-by-side may be a cost effective design solution given the wide bridge width. This can be approximated in the program by inputting one-half of the structure with a single hammerhead pier, then doubling the quantities. Short land piers are more likely to use multi column intermediate supports. The program assumes a single hammerhead pier for a given bridge cross section and limits the bridge width to less than or equal to 70 ft.
Span Length Guidelines Span Length Ranges by Superstructure Type Modify the number of intermediate supports within the segment or modify the structure type such that the calculated average span length falls within the span ranges given in the table. Min SpanMax. Span FIB40* 175 FUB40* 135 CIP Flat Slab1550 Steel Box120320 Steel Plate Girder120320 * When the calculated average span length exceeds 130, verify feasibility of hauling FIB to the bridge site.
Bridge $ / SF Screen Optional Items Screen Bridge Level Detail Screen Bridges Tab Bridge Summary Screen Edit Cost / SF Edit Detail Cost Segments Summary Segment Detail Bridge Screens Flow Optional Items Tab Segments Tab End (Back to Summary or Bridge Tab)