01/01/1992 10780

BRIDGE AND STRUCTURAL DRAFTER

DEFINITION: This is technical work in the preparation of a wide variety of bridge and structural plans, maps, and similar drawings.

An employee in this class performs technical duties which follow prescribed methods and procedures, and involve the application of basic technical skills and techniques for the completion of a wide variety of drafting and moderately complex design assignments with professional guidance from higher level technical employees. Work is performed using Computer Aided Drafting and Design (CADD) instruments or conventional techniques and methods and involves preparing and checking mathematical calculations, and reducing field notes preparatory to drafting. Employees may function as a lead worker over lower-level technicians preparing simple tracings or straight-line drawings. Work is performed with general instructions received in the form of rough notes or incomplete sketches. As assignments increase in difficulty, more detailed instructions may be received from a higher level technician, designer, or technical supervisor who reviews work upon completion for accuracy and adherence to established standards.

EXAMPLES OF WORK: Assists in the preparation of bridge and structural plans from field survey notes.

Performs all drafting and detailing work associated with the development and preparation of bridge and structural plans from preliminary sketches to final detailed working plans.

Prepares portions of plans for bridge and structural projects such as fixtures, equipment, beams, connections, and foundations.

Plots alignment of structures, topography and profiles; details abutments, piers, culverts, arches and retaining walls; plots and calculates drainage areas and waterway profiles; and draws structures to scale on plans with professional and technical guidance.

Reviews bridge and structural plan drawings to ensure proper drafting procedures were applied and checks various quantity calculations; and redrafts plans to correct possible problems with professional or technical guidance.

Performs mathematical calculations necessary to compute quantities of materials such as volume of concrete, length and weight of steel reinforcement bars, volume of excavation necessary and other related computations. Performs horizontal vertical bridge geometry computations and other technical location and quantity computations with professional and technical guidance.

Details structures such as reinforced concrete box culverts, simple span settle I-beam bridges and metal plate culverts; and details final bridge plans from a designer's preliminary sketches on bridge design or bridge rehabilitation projects.

Performs tasks in applying and interpreting survey notes, aerial photographs, and engineering data.

May participate in field trips to assist in making measurements and sketches.

May inspect bridge structural members, foundations, supports and components under the direction of engineers, inspectors, or higher level technicians.

Performs related work as required.

REQUIRED KNOWLEDGES, SKILLS, AND ABILITIES: Knowledge of CADD methods, instruments, materials, and techniques used in bridge and structural drafting.

Knowledge of conventional technical drafting principles and practices involved in the preparation of technical bridge and structural plans and drawings.

Knowledge of the algebra, plane geometry, and trigonometry used in reading and checking engineering instructions for drafting.

Knowledge of departmental drafting standards.

Knowledge of the symbols used in structural drafting.

Knowledge of the practices of surveying required to reduce surveyors' field notes to working maps.

Ability to use computer aided and conventional drafting and design instruments and equipment.

Ability to read and interpret maps, plans, aerial photographs, blueprints, survey notes, and other records.

Ability to letter in freehand and with a mechanical lettering set.

Ability to care for drafting instruments and equipment.

Ability to establish and maintain effective working relationships with associates and departmental personnel.

MINIMUM EXPERIENCE AND TRAINING: One year as an Engineering Technician.

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Two years of experience in a variety of drafting assignments, one of which shall have been in bridge and structural drafting, including six months CADD experience or training, and graduation from high school.

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One year of experience in bridge and structural drafting and detailing assignments including six months of CADD experience or training and an Associate's Degree in civil engineering, drafting, or design technology.

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Any equivalent combination of experience and/or training.