Our Project brief requires us to prepare manually measured drawings, the
basis on which conservation work of the structure and fabric can be directed.
A - Preparation
to Work - Reconnaissance survey was
conducted of the building, whose base measured 25 mt by 18mt, having 4
floors (12 spaces in the ground floor, 8 in the first floor, 5 in the second
floor, 2 in the third floor and terrace). Based on the drawing provided by the
ASI, the spaces were numbered as S1 to S-N, in an anti clock-wise manner
(Refer to Photographs- Naming of Spaces and Phasing for Measurements) and a reference diagram was made prior
to commencement of work.
B - Identifying Tools
- Given that the work
was commissioned to only 2 people, a process that provided
accurate information yet is time efficient has to be selected. Also, in
the absence of standards tools - such as a laser-cross-hair, inclinometers,
disto-meter, total station, auto-leveler, digital spirit-level, the method to
be resorted had to be manual, with basic tools - spirit level, string, chalk
and measuring tape. Therefore, the schedule of work and time-frame had to be
revised.
C - Identifying
bearing points and measurements - It was decided by the
consultants that the built profile (floor plans) would be drawn by
triangulating from an established reference plane. It must be mentioned that
the reference planes are normally established outside the structure to be
measured. However, in this case, fixed bearing points available are more than 8
meters from the built profile. Over this length, measurements taken
are erroneous due to sagging of the tape. Moreover, the site being overtly
visited, it is impossible (also requiring permission) to erect a temporary
bearing point which will last 6 months (the length of project time). As a
result, it was decided that an internal-grid would be established, from which
measurements for the internal profile would be acquired and later, from the
elevations, the external profile would be drawn.
D - Phases of work - First, the profile of
the interior spaces would be drawn, thereon, smaller details, that measure less
than 1 meter i.e. mouldings, interior of niches, details and the profile of the
floor, would follow. (Refer to Photographs - Phases of Work - Measured drawing
of Floor Plan along established Datum Line)
Phases of Work - Measured drawing of Floor Plan along established Datum Line |
Following the profile of the floor, would be the external elevations.
For this a vertical reference grid at 2 meters interval would be established
and measurements will be taken by a combination of methods - i.e. by
triangulating and from rectified photographs (Refer to Photograph- Vertical
reference grid along the North Facade).
Vertical reference grid along the North Facade |
E - Tests and
Assessments - Based on the reconnaissance survey, a list of tests were also
recommended as necessary-
- Tell-tales along cracks,
separation joints which are possibly active
- Excavation along at 4 points
to assess condition of foundation (before rain)
- Tests to identify
composition and condition of plaster, mortar, bricks, flooring material
(at different level and points)
- Noting of changes in
moisture levels, rising dampness etc
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