Common InfraBIM Requirements YIV2015

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Common InfraBIM Requirements YIV2015 Vol 5.2 Preparation instructions for as-planned models of earth works (machine control model) MODELS: EARTH WORKS, FOUNDATION AND ROCK CONSTRUCTIONS, SUB- BASES AND PAVEMENT STRUCTURES Quality control Interaction and collaboration Supervision and coordination Infra modeling Coordination of disciplines Gathering of initial data Planning, construction, asset management Sami Snellman Destia Oy

Sami Snellman Destia Oy Document version history Version Date Author Description 1.0 31.3.2015 Sami Snellman Further editing 1.1 6.7.2015 Kimmo Laatunen Translation draft

2 (20) CONTENT 1 Introduction... 3 1.1 General... 3 2 Content of as-planned model... 4 2.1 Modelled objects... 4 2.2 Modelled terrain break lines... 6 2.3 Naming and coding of terrain break lines and surfaces... 7 3 Accuracy requirements for as-planned model... 10 3.1 Continuity of terrain break lines and surfaces... 10 3.2 Geometric accuracy of terrain break material... 12 3.3 Regularity of triangulation network... 14 4 Material handed over to orderer... 16 4.1 Checking of material... 16 4.2 Data model report... 16 4.3 Naming of as-planned model files... 16 4.4 Data exchange format of as-planned model... 18 References... 19

3 (20) 1 INTRODUCTION This part defines content as well as accuracy requirements for as-planned models used in construction of road, street, railways and other general areas. The goal with uniform procedures is to produce homogeneous as-planned 3D models in final engineering stage, which can as directly as possible be used in control systems of work machines. Requirements concern only as-planned models produced in final engineering stage. For other respects, the contents of handover materials in construction projects follow client existing instructions and requirements. 1.1 General Machine control automation means use of 3D control systems in working machines in construction of infrastructure. In automated sites, the work machine is equipped with sensor, tracking device and computers, to which the digitalized design data is brought. Machine operator sees the 3D as-planned model (machine control model) and the real-time position from a screen, and the design doesn t need to be marked in terrain anymore. Machine control automation is a faster and more accurate way to implement construction design in the terrain with the machine control model. As-planned model is a model made from design data of the construction object. It consists throughout of continuing 3D terrain break lines and their triangulation net models. The site can utilize only the 3D break line material, only triangulation net models or both, depending on purpose. At the moment there is no design program, which can directly produce models according to requirements. Today a separate modifying stage is needed to fulfil the requirements. Modifying means, for example, removing additional terrain break lines, adding terrain break lines or naming material.

4 (20) 2 CONTENT OF AS-PLANNED MODEL In this part are road, street and railway models as well as constructions in industrial areas studied. Asplanned model for infrastructure consists of many different entities of different construction surfaces. Every single construction surface is its own separate as-planned model and all construction surfaces forms an as-planned model of the built object. 2.1 Modelled objects Requirement All those constructed parts, where machine control is used in their implementation, have to be modelled. Instruction As-planned model for infrastructure consists mainly of following INFRA 2006 and project nomenclature construction components: 1400 Foundations 1600 Soil cuts and excavations 1800 Embankment, earth dams and fillings 2100 Pavement structure 2400 Pavement structure for railways For other construction components, the same principles can be followed. Components 1400, 1600, 1800, 2100 and 2400 are the most commonly modelled surfaces (according to InfraBIM nomenclature): Top combination surface Asphalt AB of wearing course, top surface Unbound base course, top surface Sub-base, top surface Filter course, top surface Lowest combination surface Excavation for replacement of soil Excavation for pipes and cables Earth embankment, top surface Frost insulation, lower surface Frost blanket course, top surface Base course, top surface Paver base, top surface Bottom of paver base, top surface Open ditches and ducts In principle are all surfaces needed in construction modelled. It can be separately decided, for example in tender, if some surfaces are not to be modelled in a project.

5 (20) For structural courses and embankment constructions the top surface is modelled: in cuttings, the lower surface of construction is modelled. Changes in structural course thicknesses are included in as-planned model. These can be for example connection points between highway and ramp, where sub bases of ramps often are thinner than the sub bases of highways. Likewise can structures of secondary road be of different thickness as for main road. The change in structural course thickness is designed according to existing instructions. In these changing points of thickness, where no transition wedge is built, the change in thickness is made on a 5 m distance on the side of bearing substructure [2]. Transition wedges are designed according to existing instructions. Position of transition wedges are registered in design documents, and checked on sites according to InfraRYL to be in accordance with terrain conditions, so the deepest point of wedge is made in the connection point of substructure [2]. If the accurate position of transition wedge is already known in the design stage, the transition wedge is to be implemented in the as-planned model. Very often, when the position of the transition wedge is close to a drum, it is implemented in to the as-planned model. The actual position of some transition wedges is however not clear until at site so modelling of these can only be made during construction. Example The exact change point of rock cuttings isn t generally known in the final engineering stage, but the design is based on interpreted rock surface. Transition wedge can, if needed, be modelled when rock surface has been dug out. Transition wedges can also be modelled in accordance with interpreted surfaces, if separately agreed upon. In this case, it has also to be mentioned in the model report. Instruction Earth excavations are designed according to existing design instructions and as-planned models are prepared from them as separate surfaces. For modelling, the division of responsibilities is the same as in the design. As-planned model doesn t replace the excavation plan and no responsibilities are defined in it. If modelling is based on interpreted surface, this has to be mentioned in model report. For asphalt surfaces, the top surface is always modelled (Asphalt AB of wearing course, top surface). If the thickness lower substructures differ from top surface, also the lower substructures are modelled. Another substructure according to InfraBIM nomenclature, which can be used, is asphalt ABK for base course, top surface.

6 (20) 2.2 Modelled terrain break lines Requirement For every surface is in principle only modelled those terrain break lines, which has a fold or line in surface structure or is significant in another way. Alignment of road is always modelled, even though the road has one-sided sloping. The surface may not have overlapping terrain break lines. Example In the top combination model, no terrain break line is made for alignment of road, because there is normally no terrain break line. In other words, the inclination of road doesn t change. In picture 2.1 the inclination of bus stop is outward and unilaterally into inner curve of carriageway, and a fold is formed at the bus stop. Name and code of terrain break line are defined by position of inclination line of road, according to Infra- BIM nomenclature. Picture 2.1 At the bus stop is a break in surface, which should be modelled. In objects like dumping grounds, mines, different infiltration drain fields, urban runoff vats, roundabouts and parking lots is only modelled those terrain break lines, where the inclination is changed or where there is a fold in the surface.

7 (20) 2.3 Naming and coding of terrain break lines and surfaces Requirement For construction surfaces of as-planned models is followed numbering and naming policies according to InfraBIM nomenclature. Instruction Different construction surfaces can have terrain break lines with same names and codes. Every construction surface is a separate surface in the as-planned model. As-planned models for construction surfaces are independent surfaces. They are not dependent, even though they are compatible with each other. Names and codes of terrain break lines and construction surfaces according to InfraBIM nomenclature are exemplified in pictures 2.1-2.6. Nomenclature for terrain break lines is based on Tie- ja ratahankkeiden maastotiedot mittausohjeeseen (Terrain data and surveying instructions for road and railway projects). For example in picture 2.2, the edge of substructure has code 122 and the ditch bottom has 141 in the as-planned model. Terrain break lines have same codes regardless of which side of the road the line is on. For example, position of terrain break line in relation to road alignment can graphically be checked. Goal with naming and coding is to use same naming and coding policy in all modelling phases. Picture 2.2 Codes and names of terrain break lines according to InfraBIM nomenclature of top surface in combination model.

8 (20) Picture 2.3 Terrain break lines in as-planned model for road specified per substructure according to Infra- BIM nomenclature. Names and codes of construction surfaces are determined according to Infra 2006 Rakennusosanimikkeistö, (construction components nomenclature). Picture 2.4 Names and codes of construction surfaces in as-planned model for road according to InfraBIM nomenclature.

9 (20) Picture 2.5 Terrain break lines in as-planned model for railway specified per substructure according to InfraBIM nomenclature. Picture 2.6 Names and codes of construction surfaces in as-planned model for railway according to Infra- BIM nomenclature.

10 (20) 3 ACCURACY REQUIREMENTS FOR AS-PLANNED MODEL Accuracy requirements for as-planned model can be divided in continuity and geometric requirements for terrain break lines and surfaces. Final accuracy requirements for infrastructure are defined according to publication InfraRYL Infrarakentamisen yleiset laatuvaatimukset Osa (InfraRYL general quality requirements for infrastructure construction, Part 1). Quality requirements are shown as deviations between the ready construction and the designed. In this chapter are defined accuracy requirements for as-planned model. For all surfaces is followed same accuracy level. 3.1 Continuity of terrain break lines and surfaces Terrain break line is a chain consisting of many straight lines, which have the exactly the same x, y, z coordinates with each other, the intersection of the previous line and the following line. Those terrain break lines form surfaces. Requirement In an as-planned model, all terrain break lines and surfaces have to be throughout continuous. In the same surface shall not be vertical changes as well as no overlapping terrain break lines. When a fairway unite with another fairway, there is allowed up to 1 m gap between terrain break lines at the connection point. The whole as-planned model for a project consists of many different surfaces and parts of fairways, which seamlessly fit together. Instruction Terrain break lines shall be continuous also in uniting areas (also roundabouts), exit and merging lanes as well as places with change in construction. If there is less than the allowed 1 m gap between the terrain break lines of different fairways, the terrain break line material shall anyway form a uniform 3 D surface. In other words, no notches may be formed on surface in the gap between terrain break lines. Where construction type changes, the constructions are intended to connect seamlessly to each other, if it is possible. Continuity of surfaces can be reviewed, among others with the help of contours, sections and 3D views. Example No discontinuities shall be formed on terrain break lines and surfaces. For example, all intersection areas shall be designed in such a way, that main road terrain break lines form a uniform model with the terrain break lines of intersecting secondary road. In some construction type changes (for example, lower combination surface of deep road bed and embankment), the surfaces don t form uniform surfaces in reality. Then the terrain break lines can be left unconnected with each other.

Picture 3.1 Terrain break lines shall be continuous and parallel per fairway 11 (20)

12 (20) Picture 3.2 Examples of continuity of terrain break lines and surfaces in the intersection area. 3.2 Geometric accuracy of terrain break material Requirement

13 (20) Terrain break line in an as-planned model shall not differ from the calculated road alignment over 3 mm (picture 3.3). A single terrain break line shall not be over 10 m long. Instruction Deviations from calculated alignment are created in circular curves (vertical and horizontal curves). A suitable accuracy level is currently formed to about a 3 mm theoretical accuracy. Then as-planned models are accurate enough in relation to design model, but not too heavy to be used by control devices of working machines. In preparation of as-planned models, one has taken into account both vertical as horizontal geometric values. A smaller radius is determinative. As-planned model alignment Calculated alignment Picture 3.3 Distance of terrain break line cant differ over 3 mm from curve in design model. Accuracy requirements can be achieved in several ways depending on design software. By software can a point for example always be always added, when the distance exceeds the vertical or horizontal geometric distance with 3 mm. Accuracy requirements can also be achieved by following certain maximum lengths of terrain break lines in comparison with curves and round edge radius (Table 3.1 and 3.2). Minimum length of terrain break line can be regarded 0,5 m, unless it is a special object, for example a curve of top of noise barrier, tight intersection curve etc. which require denser terrain break line chain for a successful modelling.

14 (20) Table 3.1 Maximum length of terrain break lines with different values of curve radius (R) and round edge radius (S) in as-planned models. Curve radius R / Round edge radius S Maximum length of terrain break line (m) 1 39 R / 40 (0,5 m minimum) 40 149 1 m 150 999 2 m 1000 3999 5 m 4000 10 m At transition curves (clothoids), the same policies are followed as for curve radius. In table 2 are defined the maximum values, with which enough accuracy is achieved. Table 3.2. Maximum length of terrain break lines along road with different transition curve values. Parameter of clothoid A (m) Maximum length of terrain break line (m) 40 79 1 m 80 499 2 m 500 999 5 m 1000 10 m For terrain break lines in terrain surface borders, as for top edge of slope or lower edge of embankment, can the length of terrain break line be about 1 m, in which case the terrain break line chain follows accurately enough terrain contour. 3.3 Regularity of triangulation network Instruction In control devices of work machines, the terrain break line model is used in addition to triangulation models of construction surfaces, which are formed by triangulating terrain break line material. Triangulation can be performed with many different software and triangulation is mainly made with different software and with same calculation principles. The goal is to create a regular triangulation model as possible, or the triangles should be attached with even distances to the same terrain break line. The goal is best reached when the longitudinal lines of terrain break line chains are defined to piles, for instance every 5 or 10 meter. The regularity of triangulation model is also affected by, if the terrain break line material has overlapping terrain break lines. With a regular triangulation model it is easy to visualize a construction surface well. A sufficiently regular triangulation model is achieved by following terrain break line lengths shown in instructions.

15 (20) Picture 3.4 Example of a sufficiently regular triangulation model. Picture 3.5 Perspective of a sufficiently regular triangulation model.

16 (20) 4 MATERIAL HANDED OVER TO ORDERER 4.1 Checking of material Requirement The material shall be checked before handed over and possible deviations have to be fixed. If deviations still occur in the as-planned model, they have to be recorded in the as-planned model report with explanations and marked in material. Instruction The goal is to ensure, that the material is according to requirements. Before handing over the material, designer shall check among other following things in the as-planned model: All requested construction components are modelled. All terrain break lines are uniform and continuous (taking into account the allowed deviations in requirements). No overlapping terrain break lines are in the same surface. No additional lines or points are in the material. Surfaces have no discontinuity points (taking into account the allowed deviations in requirements). Surface inclinations are according to design model (for instance studied with contours). Triangulation net is uniform enough. As-planned model corresponds to design model according to accuracy requirements in instruction. Material is in right coordinate system and datum. Material is in right format. 4.2 Data model report Requirement A data model report is produced in connection with the making of as-planned model. In data model report is shown basic and identification data for as-planned model: Name and location of project Compiler of final engineering/as-planned model Software, with which as-planned model is produced Deviations in as-planned model with comments Format of as-planned model Used coordinate system and datum Names of as-planned model files Description of content in as-planned model. Data model report is more specifically described in part 2. 4.3 Naming of as-planned model files Requirement

17 (20) As-planned files and folders are named descriptively, so the content can be clearly seen from name. No Scandinavian letters (å, ä and ö) or special characters should be used. Length of file names should also be short enough. Construction surfaces of as-planned models are named according to following examples: Road: Vt4_0-1000, or first is code of road (Highway 4), then abbreviation for construction surface Yyp) and finally cross section interval (0-1000) Railway: Kpa-Tuo_Yyp_669700-670100 or abbreviations of traffic operating points (Kpa-Tuo), code for construction surface in question (Yyp) and cross section interval (669+700-670+100). Instruction As-planned files are assembled in folders per surfaces or fairways, which are handed over to orderer. For example specified per surface: Top combination surface 201000; Asphalt AB of wearing course, top surface 214111; Unbound base course, top surface 213100; Bottom of paver base, top surface 241020 are all their own folders. Folder division specified per fairway can be as follow: Every fairway has its own folder Every fairway folder is divided into 3 subfolders: geometry, terrain break lines and triangulation nets Fairway data for the fairway in question is saved in subfolders (fairway, surface, cross section interval) Every construction surface in as-planned model is modelled into their own as-planned model file per fairway. Names, numbers and abbreviations for surfaces are named according to InfraBIM nomenclature instructions. Examples of names, codes and abbreviations used in naming construction surfaces are in table 4.1. Table 4.1 Examples of naming as-planned models according to design surface names, codes and abbreviations in InfraBIM instructions Name of substructure Abbreviation Code Top combination surface Yyp 201000 (240000) Asphalt AB of wearing course, top Kant1 214111 surface Unbound base course, top surface Sitk 213100 Sub-base, top surface Jak 212100 Filter course, top surface Suod 211100 Lowest combination surface Ayp 201200 Sub base, railway, lower surface Tukao * 241020 Paver base, railway, top surface Tuk * 241010 Interlayer, railway, top surface Val * 212300 Frost blanket course, railway, top Eris * 212200 surface Geotextile Skang * 211200

18 (20) Filter course, railway, top surface Suod * 211100 Top surface combination surface of substructure Ayyp * 210000 Fairway construction, lower surface Vap 201100 Preloading bank Epe * 181600 Loading berm Vpe * 181500 Earth bank, top surface Mpe 181100 Excavation for replacement of soil Mv * 162500 Excavation for pipes and wires Putk 162100 Frost insulation, lower surface Routa * 142100 *suggestion on abbreviations to be added into infrabim nomenclature. 4.4 Data exchange format of as-planned model Geometric lines All calculated geometric lines (also edge lines, islands etc.) are handed over to orderer in accordance with LandXML standard of Inframodel data exchange format. Terrain break material of as-planned model Terrain break line material of as-planned model is handed over to orderer in accordance with LandXML standard of Inframodel data exchange format. Triangulation network material of as-planned model Terrain break line material in as-planned models is handed over to orderer in accordance with LandXML standard of Inframodel data exchange format. In exceptions it can further be handed over as dwg-files, if they percieve to deliver added value.

19 (20) REFERENCES 1 InfraBIM-nomenclature 2 InfraRYL 3 Liikennevirasto (2011) Tie- ja ratahankkeiden maastotiedot 4 Tiehallinto (2008) Tierakentamisen mittaussuunnitelman laatimisohje