DESIGN SPECIFICATIONS

Post 615 –by Gautam Shah

.

640px-BASF_Werk_Ludwigshafen_1881

Primary instinct for a human effort is to create a Recipe or Process. We tend to perceive an item by hypothetically enacting its process. First step is compilation of a list of physical inputs (ingredients). Second step is forming lists of things to do, how to do and not to do (human interventions). Third step is planning the sequences in time. Fourth step is readying tools required for various processes. A fair mix of all FOUR steps can offer an object, but not a desired entity. The end result is conjectural. In real design work intentions are additionally transmitted through drawing documents and other forms of surrogates.

1024px-Boullée,_Etienne-Louis_-_Project_for_a_library

499px-jean-franc3a7ois_millet_28ii29_005

Oven Cooking > ART by Jean-Francois Miller (1814-1875)

Item or design specifications have been used for execution, manufacturing, fabricating, erecting, for procuring ready-made objects, and also for effecting various services. The term Design here means any scheme, as such orally conveyed, written, drawn, or otherwise implied.

14847544245_47568fe056_c

A Design or Scheme specifies aspects like : constituents, processes of combining, synthesizing a coherent entity or system, method of care and handling the men, materials, tools, equipment and the entity itself as it is being created.

639px-konrad_kyeser2c_bellifortis2c_clm_301502c_tafel_092c_blatt_38v_28ausschnitt29

Elevator Design by German Engineer Konrad Kyeser (1405) Wikipedia image

When a design (recipe) is specified for a product, and once readied (with reasonable sincerity), a client has to pay even if it fails on acceptability count. As a result, writing Item or Design Requirements is not an assuring process, unless the specifiers have had recent experience, at designing nearly Identical Items, and fully comprehends all aspects of the design problem.

640px-design_management_in_brief

Design confusions > Image attribution: Wiki4des at English Wikipedia

Specifications for a Designed Object

A Designer prepares design specifications, (materials + procedures + conditions of origin), so that the contractor or vendor can provide the stated item. The contractor or vendor gets very exact data, but little freedom to use alternative materials or execute it differently. If there is an uncommon item, the contractor will invariably charge more for the extraordinary effort or customization. This process does not assure that in spite of a sincere execution and diligent supervision a functional product will be delivered. The Item specifications specify ‘physical adequacy of the item while seeking a hypothetical performance’.

shipelevator-shipyard-yard-structure-workshop-repairs-niederfinow-germany

A contractor or vendor is better aware of latest materials, processes, technologies and their costing as available in the market, In comparison to any specification formulator like a designer. A contractor or vendor, if allowed to provide, can offer an item that surpasses the one conceived in the ‘item or design specifications’. This cause was identified by US Air-force and made it mandatory to procure entities by PERFORMANCE SPECIFICATIONS, through the ITEM or DESIGN SPECIFICATIONS. A performance specification states the exact requirements of performance of an entity, and no materials + procedures + conditions of origin are given. This is an appreciable method but very difficult to implement. Performance of some of entities cannot be checked-validated over a longer time span (e.g. Operative suitability of a submarine beyond 20 years).

Performance specifications are partially used in many works with item specifications. For example, 6/7 decades back many builders were asked to refer to Standards for Cement, Sand, Aggregates, Water, Mixing procedures and testing methods for quality to be achieved. This is now replaced by pre-mix cement concretes of assured quality. This a way of relying on the performance, than Materials+Processes methods.

640px-mercedes-benz_axor_based_cement_mixer_truck

Ready-mix Concrete > Wikipedia image by High Contrast

Specifications for acquiring some ready-made objects can be Performance specifications but tend to be even more restrictive. A specifier (buyer-acquirer) of a ready-made item of the market shelves has no way of verifying a product, so relies on average standards followed by the Industry, or match with some ‘super’ supplier’s (top product in the market) specifications. Failing either of the conditions, one, has to pay the extra cost of customizing a regular or standard item. In the later case the assurance nominally available for the regular or standard item are unlikely to be offered for the altered form.

iran-isfahan-art-mosque

.

DEBRIS of BUILDINGS

Post 405 – by Gautam Shah 

.

640px-The_Roman_Town_Wall,_Head_Street_to_the_Balkerne_Gate_3

Buildings are formed of huge volumes of materials. The materials of construction come to the site in small lots and over a long period of execution. Older buildings are likely to have greater volume of materials than any of the recent constructions. Recently constructed buildings are likely to have lighter but highly articulated forms. The composed materials and their integrated geometrical makeup make it difficult to demolish and separate the materials. For older buildings the recovery or recycling process involves large volumes and simpler mix of debris, whereas for recent buildings the recovery process is smaller but its complex mix of debris makes the recycling process difficult and costly.

Fotothek_df_ps_0000433_Ablagerung_für_eine_später_einsetzende_Großblockproduktio

Debris has been a problem of human settlements since prehistoric times. The problem was complicated because agricultural wastes of farms, excreta of humans and animals, ashes, broken pots, and kitchen garbage, all were dumped together with useless building materials. Some of the wastes like bones, skins, hairs, feathers, etc. were managed away from the settlements. Stems and husks of agro-products were managed at form locations. Organic wastes of animal urine and excreta were recycled for building finishing materials or as fuels.

Dholavira, Gujarat, India Excavations Wikipedia Image by Rama’s Arrow

Old historic sites show predominantly broken pots and rubble of building materials. Both of these forms are nearly indestructible, so last for a very long period. These materials were often used for land fill or leveling, but otherwise new buildings constructed over the dump. For example, Mohen-jo-daro and other Harappan sites, and ancient Vadnagar (Gujarat – India), are such hillock sites.

Ruins of Tiferes Yisrael synagogue Jerusalem

Disposal of debris is mainly of course a problem of transporting the waste to locations away from the settlements, but it was also due to the inability to use the older building materials like clay, broken bricks, pots or ceramics. Stone, however, is recyclable material to the smallest piece. Romans constructed many buildings with stones, and these were reused not only used in simpler dwellings, but also for mosaic and inlay work in public buildings. This activity of recycling the Roman old buildings continued for several centuries.

Quwwat ul Islam mosque near Qutub Minar New Delhi -Reused columns Image https://www.flickr.com/photos/73134341@N00/411557451

Time has not spared the Egyptian Labyrinth. The complex fell into ruin at an unknown date, but during Roman times it became the site of quarrying for its fine stone. It occupied such a number of masons that a small town sprung up on the site. When the British archaeologist Flinders Petrie excavated the site in 1888, he found nothing but a vast field of chipped stone, six feet deep.

624px-Egyptian_labyrinth

Palace of Knossos Wikipedia Image by Chris 73 

Paris, once had a similar problem of managing the debris. Paris had no paved streets or with planned storm water drainage slopes. The town became muddy with little rain. The streets were covered by local residents with hard debris. This dumping was enhanced by dumping -spreading the waste whenever an old building was replaced with a new one. This raised the street levels to upper floors, burying the ground floor, and sometimes second floors as the cellar. “It occurred at varying rates and often accelerated following demolitions in times of conflict. Such dumping also occurred just outside the city walls as artificial hills. The hills remained, as these were difficult to transpose. In Paris such mounds have been integrated into the urban landscape (Jardin des Plantes is an example of a historical dump-site). Mumbai was a land of seven islands separated by creeks, but the land has been reclaimed by dumping debris, garbage and soil.

abandoned_place_spinning_ruin_decay_factory_building_industry_transient_overgrown-488895.jpg!d

Building materials as debris result from demolition of nonviable structures, disasters and modifications. There are also mine head and on-site dressing wastage. The quality of construction materials and technology of assimilation determine the size and shape of elemental units, if any. Integrated buildings (like cement concrete) have little to offer in terms of elemental units. The process of debris formation, such step by step demolition, sudden collapse and historical neglect, determine the debris sorting, removal and reuse of materials. The reuse of material is of very high proportions for small buildings of self-help construction, historical  neglect and for simpler and low cost recycling processes.

asia_bricks_broken_calamity_disaster_home_house_india-1561263.jpg!d

640px-ONE_EXAMPLE_OF_LANDFILL_IN_MANHATTAN,_NEW_YORK._IS_THIS_SITE_FOR_BATTERY_PARK_CITY,_A_HUGE_HOUSING_COMPLEX._LANDFILL..._-_NARA_-_555813

17509898383_49481e8aef_z

The problem of managing non-recyclable debris like clay, brick and ceramic pieces may not be very acute for one or two buildings in a settlement. But when there is a massive destruction due to earthquake, floods, invasion or forced evacuation due to disease, the mound of debris is immovable. The reconstruction must occur over the old heap or mound of debris, or a new site must be found. Both of these are evidenced in history.

Disaster Debris

Earth quakes in Kutchh and other parts of Gujarat created a huge problem of debris removal and disposal for reuse or safe dumping. Debris removal from narrow streets of age-old towns using automatic machines or dumper trucks was difficult. A greater problem was how and where to dump the material, when the entire village outskirt lands are for cattle grazing or farming. Local groups sorted good and whole bricks by temporarily employing jobless local people. Few structures were constructed with these recovered materials.

010917-N-7479T-515

.