Assembling a Scaffold

To build the standard Mars Quonset out of stone blocks, a temporary aluminum scaffold will be required. This scaffold is shown in the figure below.

As shown, the lower half of each frame consists of two segments, each one 200 cm wide by 210 cm high. The horizontal and vertical members of each segment consist of aluminum el-bars that are welded together at junctions and further reinforced by aluminum plates (Alloy AA2014 for high strength). The oblique support members are made of flat aluminum bars.

Mars House Scaffold Frame
The upper four segments of the frame consist of curved inverted tee-bars of different lengths, each taking the shape of a circular arc segment with a radius of 200 cm. The curved members will consist of aluminum curved tee bars that form the arch. The radial support members will be made of straight el-bars, like the members in the lower segments. The straight radial members will have holes along their sides for bolting together the upper frame segments.

When it becomes time to employ the scaffold, the segments will be bolted together through holes on the side of each el-bar. After one section of house construction is finished, the segments of each frame can be disassembled and reassembled for the next section to be constructed. 

The length of wall and ceiling that is constructed at one time represent one section of a house.  The number of frames available will limit the length of each section that will be constructed at one time. The number of frames that the colony sponsors are willing to ship to Mars at one time will determine the number available at any one time. Each section of wall and ceiling blocks will be supported during construction by a series of scaffold frames that are placed 124 cm apart. The frames will be held upright and in their proper position by cross beams between the frames as shown in the figure below. Each crossbeam will have a perpendicular flat plate on each end with holes, so that bolts can be pushed through these holes and through holes in the upper part of the radial beams. Crossbeams will be required at the top of the arches, at the junctions of frame segments, and at the bottom of the lower scaffold segments near the floor. This is a total of seven crossbeams between two frames.

Cross Beams

To maintain rigidity along the series of frames, support bars made of flat aluminum will be inserted between frames along the sides of the scaffold in an oblique position. One end of each bar will be bolted to one vertical member near its top. The other end will be bolted to the corresponding vertical member of the next frame near its bottom, as illustrated in the figure.

Ceiling Stone Support

 

The space between the arches of two frames will be filled with a flexible support blanket. The blanket will consist of 2-inch by 2-inch square aluminum tubes 121 cm long that lie parallel to one another. The square tubes will be separated from each other by 2-inch long round tube separators. To loosely hold the support blanket together, a wire rope will pass through holes in the sides of the square tubes and through the separator tubes. Scaffold Frame LevelerFive such wires ropes will be required for each blanket. A crane will pick up one end of a blanket, lift it over the space between two frames, and then lower it onto the curved tee-bar edges of the two frames. The lowest of the square tubes will rest upon a crossbeam that lies on top of (rather than under) the two curved tee-bars and just above the junction of segments 2 and 3.. This crossbeam is places above the tee-bars expressly for this purpose. The other tubes comprising the blanket will lie on one another and on top of the lowest crossbeam. No other support should be required to hold the blankets in place while laying ceiling blocks against them. One blanket will cover one-half the ceiling arch over segments 3 and 4 and another blanket will cover segments 5 and 6.

One other item is a frame leveler (bolt and foot) that is placed at the bottoms of the vertical members of segments 1 and 2, as depicted in the figure above. The mounting bracket is placed inside the horizontal member close to where the vertical member is welded to it. Holes in the horizontal member match holes in the mounting bracket so that the leveling bolt can be screwed through both. The bolt head is accessible for turning from the top and the bottom of the bolt rests on a metal pad. This device will allow adjustments in the heights of the scaffold frames to accommodate uneven floors and small irregularities in block shapes.

 

Return to the article Pioneer House Building.