Tuesday, May 29, 2007
Sunday, May 27, 2007
Construction weakens, despite lift in house building: Australian PCI
This article reports weak growth in the Australian commercial and apartment building activity in April 2007, which has outweighed the slight improvement in the house building sector. The article further indicates that new orders have decreased and builders have resorted to discounting of house prices to boost sales. The article indicates that the weak month has already resulted in a decline in employment and reduction in supplier deliveries, and that the trend may extend to future months as a result of the reduced orders.
The article draws a distinction between commercial construction which has declined, and the residential construction market which has shown growth and an increased level of demand.
The article demonstrates the immediate impact of consumer and commercial demand for construction on the industry and further shows how responsive the industry is to the market and the actions or demands of outsiders generally.
http://www.azobuild.com/news.asp?newsID=3661
The article draws a distinction between commercial construction which has declined, and the residential construction market which has shown growth and an increased level of demand.
The article demonstrates the immediate impact of consumer and commercial demand for construction on the industry and further shows how responsive the industry is to the market and the actions or demands of outsiders generally.
http://www.azobuild.com/news.asp?newsID=3661
New Building Permits Drop To Slowest Pace In A Decade
This American article from May 2007 reports that new building permits in the US dropped to the slowest pace since 1997. Reasons for the decline include a general downward correction of the market, and more specifically tightening mortgage lending standards and an excess of vacant housing units on the market.
The condition of the market is putting increased pressure on builders in the US, who are increasing their attempt to make sales and limit cancellations. The article further discusses which type of residential buildings are declining more than others.
While this article relates to the US residential industry, which is obviously significantly more developed than that of Australia, it is interesting to understand the world wide conditions, and to consider what impact this will have on supplier and provider contracts in Australia now that we live in a global environment.
Construction weakens, despite lift in house building: Australian PCI
This article reports weak growth in the Australian commercial and apartment building activity in April 2007, which has outweighed the slight improvement in the house building sector. The article further indicates that new orders have decreased and builders have resorted to discounting of house prices to boost sales. The article indicates that the weak month has already resulted in a decline in employment and reduction in supplier deliveries, and that the trend may extend to future months as a result of the reduced orders.
The article draws a distinction between commercial construction which has declined, and the residential construction market which has shown growth and an increased level of demand.
The article demonstrates the immediate impact of consumer and commercial demand for construction on the industry and further shows how responsive the industry is to the market and the actions or demands of outsiders generally.
http://www.azobuild.com/news.asp?newsID=3661
The condition of the market is putting increased pressure on builders in the US, who are increasing their attempt to make sales and limit cancellations. The article further discusses which type of residential buildings are declining more than others.
While this article relates to the US residential industry, which is obviously significantly more developed than that of Australia, it is interesting to understand the world wide conditions, and to consider what impact this will have on supplier and provider contracts in Australia now that we live in a global environment.
Construction weakens, despite lift in house building: Australian PCI
This article reports weak growth in the Australian commercial and apartment building activity in April 2007, which has outweighed the slight improvement in the house building sector. The article further indicates that new orders have decreased and builders have resorted to discounting of house prices to boost sales. The article indicates that the weak month has already resulted in a decline in employment and reduction in supplier deliveries, and that the trend may extend to future months as a result of the reduced orders.
The article draws a distinction between commercial construction which has declined, and the residential construction market which has shown growth and an increased level of demand.
The article demonstrates the immediate impact of consumer and commercial demand for construction on the industry and further shows how responsive the industry is to the market and the actions or demands of outsiders generally.
http://www.azobuild.com/news.asp?newsID=3661
Government counting on green homes to cut emissions
This article discusses measures taken by the Federal Government in the 2007 budget to fight global warming by introducing incentives and grants for residential households to install energy saving devices such as solar power systems. The article also outlines criticisms of the current proposals as the amount of funding is insufficient to support a decent proportion of the population actually installing the systems, and the $8,000 grant will cover less than half of the $20,000 price tag.
It has also been noted in the article that the budget does not provide for solar water heaters which would help to reduce the largest energy consumption in households. The article further indicates that if the ALP is successful in the next election, it will offer low interest loans of $10,000 to implement power and water saving measures such as solar panels, rainwater tanks, roof insulation, solar hot water heaters, awnings and grey water recycling systems.
While the article does not comment directly on the construction industry, the budget measures will have a significant impact on residential builders and developers who are likely to experience a higher demand for water and energy saving devices in new homes. They should also be aware of the grants as a ‘value add’ that they can recommend to their clients, as they would significantly reduce the cost of building a sustainable home. It further illustrates how the state of the construction industry is often shaped by outside forces, in particular political decisions and policies.
http://www.industrysearch.com.au/News/Goverment_counting_on_green_homes_to_cut_emissions-25879
It has also been noted in the article that the budget does not provide for solar water heaters which would help to reduce the largest energy consumption in households. The article further indicates that if the ALP is successful in the next election, it will offer low interest loans of $10,000 to implement power and water saving measures such as solar panels, rainwater tanks, roof insulation, solar hot water heaters, awnings and grey water recycling systems.
While the article does not comment directly on the construction industry, the budget measures will have a significant impact on residential builders and developers who are likely to experience a higher demand for water and energy saving devices in new homes. They should also be aware of the grants as a ‘value add’ that they can recommend to their clients, as they would significantly reduce the cost of building a sustainable home. It further illustrates how the state of the construction industry is often shaped by outside forces, in particular political decisions and policies.
http://www.industrysearch.com.au/News/Goverment_counting_on_green_homes_to_cut_emissions-25879
Labor won't tolerate anarchy on construction sites
This article, published on 16 May 2007, reports that the Federal Australian Labor Party has plans to abolish the Australian Building and Construction Commission, should it win the next election, however ALP spokesperson, Julia Gillard defended the proposal throughout the article. Gillard argues that although the ALP does plan to remove the ABCC, it will be replaced with another similar body that she argues will do the same job in a better way.
These assurances do not go far in appeasing builders and construction companies, who have begun to build in “risk of rudd” premiums to their large contracts that are due to start in 2008. This highlights their fear that construction costs will be increased under an ALP federal government where this proposal is implemented.
This article illustrates clearly just how volatile the construction industry is at times and how it is ultimately responsive to outside environmental factors such as political policies of the Government of the day.
http://www.industrysearch.com.au/News/Fed_Labor_wont_tolerate_anarchy_on_construction_sites-25929
These assurances do not go far in appeasing builders and construction companies, who have begun to build in “risk of rudd” premiums to their large contracts that are due to start in 2008. This highlights their fear that construction costs will be increased under an ALP federal government where this proposal is implemented.
This article illustrates clearly just how volatile the construction industry is at times and how it is ultimately responsive to outside environmental factors such as political policies of the Government of the day.
http://www.industrysearch.com.au/News/Fed_Labor_wont_tolerate_anarchy_on_construction_sites-25929
Impressive Water Conservation at Boral Roof Tile Plant
This article explains how Boral, Australia’s largest supplier of building and construction materials has delivered more than a 65% reduction in mains water usage at its Carole Park roof tile plant in Queensland over the past 12 months. The article discusses how the sweeping changes at Boral have been a result of stage 4 and 5 water restrictions, and explains how Boral has implemented the changes across its business by developing a ‘Boral water grid’ and completing ‘water efficiency management plants’ for all of its sites in South East Queensland.
Boral has made water conservation one of its five key sustainability priority areas. While the article doesn’t talk specifically about construction, Boral has set an industry wide example in terms of sustainability as the largest supplier for the industry which will have potential flow on effects, increasing the ever mounding pressure for Construction companies and developers to explore environmentally friendly and energy saving alternatives in its developments. The stage 4 and 5 water restrictions currently in place in South East Queensland could quite feasibly be extended to other areas of Australia, forcing builders and other industries to consider their water usage and take active steps to conserve water.
http://www.azobuild.com/news.asp?newsID=3650
Boral has made water conservation one of its five key sustainability priority areas. While the article doesn’t talk specifically about construction, Boral has set an industry wide example in terms of sustainability as the largest supplier for the industry which will have potential flow on effects, increasing the ever mounding pressure for Construction companies and developers to explore environmentally friendly and energy saving alternatives in its developments. The stage 4 and 5 water restrictions currently in place in South East Queensland could quite feasibly be extended to other areas of Australia, forcing builders and other industries to consider their water usage and take active steps to conserve water.
http://www.azobuild.com/news.asp?newsID=3650
Green hero takes shape
This August 2006 article discusses the new shopping complex being developed by Mirvac in the Queensland suburb of Springfield. The writer is obviously impressed with the development both visually, though maps, models and artists impressions of the completed centre and also from a sustainability perspective. Mirvac has incurred significant expense to introduce environmentally friendly aspects to its development, assisting it to earn the six star efficiency rating that it is striving to achieve. The article claims that Mirvac has achieved world wide best practice in ecological sustainability through its innovative design and other energy and water saving initiatives. It has become the first Australian property company to list on the London Stock Exchange’s sustainable and ethical index, the FTSE4Good Global Index.
The article also talks about population and other growth in the Springfield area generally and the infrastructure that is being put in place to deal with the growth. Finally, the article goes on to discuss the overseas research that Mirvac undertook to draw inspiration for the project, and the impact that it will have on future Australian benchmarks for ecologically sustainable developments.
http://www.insideretailing.com.au/ONLINE/Default.aspx?tabid=335&newsid893=922&Green-hero-takes-shape
The article also talks about population and other growth in the Springfield area generally and the infrastructure that is being put in place to deal with the growth. Finally, the article goes on to discuss the overseas research that Mirvac undertook to draw inspiration for the project, and the impact that it will have on future Australian benchmarks for ecologically sustainable developments.
http://www.insideretailing.com.au/ONLINE/Default.aspx?tabid=335&newsid893=922&Green-hero-takes-shape
Saturday, May 26, 2007
Whitegoods Warehouse
This warehouse is located in Clayton, Melbourne. Its purpose is to to store and distribute various brands of white goods. The building looks similar to the layout of the office and warehouse scenario for the major assignment having a separate warehouse and office complex.
The warehouse consists of a portal frame with concrete tilt-up panels fixed to the stanchions as cladding.
The building has an approximate 40m span. It's roof is sheeted with coated steel sheeting which is fixed to the purlins. Rows of translucent sheets are used to allow light into the warehouse. Between the purlins and roof sheets is safety mesh. A UB. rafter spans to the center of the warehouse (i.e. apex).
The strut/tie is fixed to the concrete panels. The purlins are fixed to this strut using nuts and bolts via a cleat.
The universal column is fixed to the pad underneath the concrete slab with the use of cast-in hold-down bolts or chemset bolts.
Sub-grade, packing sand, void barrier, formwork and reinforcement are put in place before the slab is poured.
The movement joint shown around this column was made with the use of 12mm fibreboard which is formed into this shape. The concrete slab is poured around it and in between the form-work and column. This separation allows for movement between the column area and slab so that cracking is minimized or eliminated.
Concrete panels are fixed to universal columns using bolts and braces.
The apex shows where the beams meet in the center of the warehouse. These beams are connected with the use of bolts (rigid connection). No haunching is used in the scenario.
Roof bracing can also be seen which go through the beam and have adjustmemts which increase or decrease the tension of the bracing. The diagonal bracing is 20mm diameter rod.
The universal columns, universal beams and cut UB haunching can be seen. The gutter is supported on top of the columns with the drainage pipes run internally from the roof, fixed to the concrete panels and then through the floor slab to the main storm water drainage underneath the warehouse.
The rafter/beam is fixed to the column using bolts. Stiffening plates are fabricated onto the column by welding.
The warehouse consists of a portal frame with concrete tilt-up panels fixed to the stanchions as cladding.
The building has an approximate 40m span. It's roof is sheeted with coated steel sheeting which is fixed to the purlins. Rows of translucent sheets are used to allow light into the warehouse. Between the purlins and roof sheets is safety mesh. A UB. rafter spans to the center of the warehouse (i.e. apex).
The strut/tie is fixed to the concrete panels. The purlins are fixed to this strut using nuts and bolts via a cleat.
The universal column is fixed to the pad underneath the concrete slab with the use of cast-in hold-down bolts or chemset bolts.Sub-grade, packing sand, void barrier, formwork and reinforcement are put in place before the slab is poured.
The movement joint shown around this column was made with the use of 12mm fibreboard which is formed into this shape. The concrete slab is poured around it and in between the form-work and column. This separation allows for movement between the column area and slab so that cracking is minimized or eliminated.
Concrete panels are fixed to universal columns using bolts and braces.
The apex shows where the beams meet in the center of the warehouse. These beams are connected with the use of bolts (rigid connection). No haunching is used in the scenario.Roof bracing can also be seen which go through the beam and have adjustmemts which increase or decrease the tension of the bracing. The diagonal bracing is 20mm diameter rod.
The universal columns, universal beams and cut UB haunching can be seen. The gutter is supported on top of the columns with the drainage pipes run internally from the roof, fixed to the concrete panels and then through the floor slab to the main storm water drainage underneath the warehouse.The rafter/beam is fixed to the column using bolts. Stiffening plates are fabricated onto the column by welding.
Friday, May 25, 2007
Flatman's Timber Yard
Flatman's Timber Yard is located in Glen Waverley.
The slab of this warehouse is poured around the universal column. A movement joint is made with 'abelflex' a type of foam material which separates the column from the slab concrete. This allows for movement so that cracking in the slab doesn't occur.
The construction joint shown to the right of the column is made by pouring the slab in sections.
After each section is poured, movement joint material (e.g. fibreboard, cork, mastic, plastic or rubber) is placed in position. The next section of the slab is then poured .
The purlin is connected to the rafter with the use of a cleat which can either be welded on to the rafter during fabrication or bolted to it on site. The purlin is bolted to the cleat. Safety mesh and sarking is located between the steel roof sheeting and purlins.
20mm diameter rods are used to brace the roofing structure to help keep the structure stable when lateral forces are applied.
Steel sheeting is fixed to girts with use of self tapping screws which are drilled through straight the sheet and then the girts. The screws usually have a rubber washer which helps reduce water from entering where the hole has been made.
20mm diaganol bracing is used on the walls to reduce the effect of lateral forces. These rods are fixed on the haunching at the highest point and the column at the lowest point. Both sides have adjustements so the rods can be tensioned appropriately.
Fly bracing is bolted to the rafter/beam which reduces movement in the purlins. It gives more stability to the purlins and prevents them from over turning.
Typical column, beam, haunching arrangement (knee joint). Gurts are fixed to the column with brackets and in turn the steel sheeting which is used as cladding is fixed to the girts.
Typical apex. Beams are bolted together. No haunching is used. Purlins are located close to both sides of the apex. These are connected to the beam with the use of cleats which are welded to the beam. The purlins are bolted to the cleat.
Qanstruct Constructions Warehouse Project
Qanstruct constructions are in the process of building a warehouse with an office facing the street which is similar to the assignment scenario.
The column in this photo has a base plate which has been welded to it using a fillet weld by a fabrication company. The base plate has four holes which have been drilled through it. Chemset bolts are used to fix the column to the pad footing. Above the pad is packing sand, a void barrier (polathene), formwork followed by reinforcement. Once these are put in place the slab is poured.
The slab is poured in sections. At the front of the column a line (construction joint) can be seen which is created due to the slab being poured in sections. The first section of the slab is poured. Before the second section is poured a type of material to create a joint is installed (e.g. fibreboard, corking etc.). The second section of the slab is then poured.
This column is located in the centre of the warehouse. Formwork has been installed in a circulation shape around the column. The slab around this column has been poured in four sections as indicated by the lines veering off in four differnt directions. Generally, columns are located on grid lines which are shown on working drawings.
During fabrication, cleats with holes which have been punched or drilled out are welded to the columns. These are used as a means of fixing girts to columns. Attached to these girts are the steel sheets used as cladding which are fixed to the girts using screws with rubber washers.
Cross bracing for the walls is used. One end of the rod is fixed to the beam and the other to the base of the column as above. A thread exists on the rod which goes though the adjustment plate. A bolts is used to tension and loosen the rods. The building can be plumbed and leveled with the use of this bracing system.
The slab in this photo has been prepared and ready to pour. The void barrier (polathene) has been laid out and formwork has been put in place and fixed with wooden pegs. The concrete will be poured to the level of the formwork in the slab (not the level of the formwork around the columns). Generally 4 to 5 days will be required before the concrete is at a structurally acceptable MPa rating.
Fly bracing is located at regular intervals. This reduces over turning of the purlins. These are bolted to the purlins and bolted to a bracket which is welded to the beam/rafter.
This photo also shows fire services which have been installed prior to the installation of the slab. Having the structure installed before the slab eliminates the possibility of inclement weather affecting the pouring of the slab. The slab could have been poured before the structure was complete but problems in relation to weather such as too much or too little heat, rain, humidy can affect the ability to pour the slab.
The structure has been completed and part of the slab poured. Formwork has been positioned for construction joints in the slab and isolation joints around the columns. Concreters have begun to roll out the void barrier. When complete the slab wil be ready to pour.
A mechnical screeding machine is used to level and compact the concrete. During the concrete pouring process the concrete is placed by concreters, the mechanical vibrator eliminates air entrapped in the concrete and then a screeding machine is used. The machine has a hydraulic arm which advances and retracts so it can level and compact.
With the use of concrete truck the concrete is transported from the concrete plant to site and poured as required. Concreters work the concrete with shovels.
The mechanical vibrator in this photo is used to vibrate the concrete from the inside. It is placed into the concrete quickly and removed slowly. It helps remove air from inside the pour which gives the concrete a higher compressive strength.
After the mechanical screed process is finished bull floating is done to flatten the surface and elimante surface cracks.
Monday, May 21, 2007
Spencer Street DFO
Spencer Street DFO is a portal frame structure with concrete panel walls. It has been architectually designed and highly engineered. Due to the level of architecture involved I was only given permission to take photographs if the Project Manager walked me around.
Towards the top of this column is a bracket that has been welded to it. A steel hinge plate has been welded to the end of the spanning member (beam). Steel leaves are welded to the ends of beams. These leaves have holes drilled out of them. The holes of the bracket and leaves are lined up and steel pin inserted to fix the beam to the column.
Intermediate columns, beams and braces are used to support the structure. The columns are installed first. The beams are then attached and fixed to other columns either side. The braces or struts are later fixed to primary beams when the roof primary structure is being constructed. 
The column and beam are connected by bolting. Bracing and struts are connected by bolting. During fabrication the haunching, and brackets and welded in position.
This photo shows a close up of the pin connection of the intermediate columns, beams and struts/braces. It is a much neater finish than when nuts and bolts are used.
The structure of this frame is made from steel beams and columns. The roof structure consists of safety mesh, insulation, purlins, bracing rods, connection brackets such as cleats. However, this design is different to the basic portal frame as their are columns located throughout the building which have secondary supports which are on an approximate 45 degree angle. These struts/braces are connected to the beam with a steel pin. This connection looks as if there may be movement at this location as it is not bolted or welded. This type of connection is a very neat detail and looks impressive.
Purlins are attached to the rafters/beams with the use of cleats which are joined by welding. The purlins are attached to the purlins by bolting.
Towards the top of this column is a bracket that has been welded to it. A steel hinge plate has been welded to the end of the spanning member (beam). Steel leaves are welded to the ends of beams. These leaves have holes drilled out of them. The holes of the bracket and leaves are lined up and steel pin inserted to fix the beam to the column. 
Intermediate columns, beams and braces are used to support the structure. The columns are installed first. The beams are then attached and fixed to other columns either side. The braces or struts are later fixed to primary beams when the roof primary structure is being constructed.
The column and beam are connected by bolting. Bracing and struts are connected by bolting. During fabrication the haunching, and brackets and welded in position.A gutter can be seen in this photo with the stormwater draining pipe. Storm water pipes are fixed to the guttering at regular intervals. The pipe runs horizontally and is sloped at approx. 1:200 so that water can be drained away and ensures that no water remains stagnant in the pipework.
This photo shows a close up of the pin connection of the intermediate columns, beams and struts/braces. It is a much neater finish than when nuts and bolts are used.
Columns are fixed to a structural element below the tile flooring. It is possible that this column is fixed to a plinth below with the use of cast-in hold down bolts or chemset bolts. Another pour of concrete for the slab is poured over the plinth and bolts so that a flat slab is poured and tiles then fixed to the slab. A concrete pour is done directly over the conrete structure below.
Another method/process would be to bolt the column directly to the slab below (which is actually the ceiling of the first floor). It would be connected with chemset bolts. The slab would then be poured covering the base plate and bolts.
A form of glue is used to fix the tiles to the slab below. The spaces created between tiles are made with the use proprietary materials which are positioned between adjoining tiles. When the tiles are fixed in position grout is used to seal up the spaces with the use of a trowel like implement.
Glen Waverley Medical Consulting Suite
The Glen Waverley Medical Consulting Suite is still under construction. It has two levels. The ground level is made from pre-cast concrete panels while the top story is constructed mostly from steel structral memebers.
The roofs structural members are fixed to the concrete panels using chemset bolts. All bolt/fixing locations have been co-ordinated off site. Shop drawings have been created by the fabricator which have been reviewed by the engineer and architect. Once amendments have been made (if necessary) the fabricator begins the fabrication process.
The feet of the brace are held into position with bolts. When it time to remove the bracing (when the concrete panel is stabilised by other memerbs around it), the bolt will be removed and the hole can be filled with cement.
Purlins are braced at right angels keeping them from over turning and to reduce the effects of lateral forces. Rods of 20mm diameter are also use to reduce the effect of these forces and carry loads to the load bearing members. Again for safety purposes, mesh is installed above the purlins which stops workers from falling through the roof members onto the ground/floor below.
Pre-cast concrete panels are used on the ground floor. The panels are constructed off site and delivered to site on a truck. Panels are manufactured by laying reinformcement in a mould followed by the concrete (concrete MPa will depend on function). 
The roofs structural members are fixed to the concrete panels using chemset bolts. All bolt/fixing locations have been co-ordinated off site. Shop drawings have been created by the fabricator which have been reviewed by the engineer and architect. Once amendments have been made (if necessary) the fabricator begins the fabrication process.
The feet of the brace are held into position with bolts. When it time to remove the bracing (when the concrete panel is stabilised by other memerbs around it), the bolt will be removed and the hole can be filled with cement. 
Bracing is used to support the column until other structural members around it have been installed and the panel is stable.
Cast in the concrete is an eye-bolt which is used as a point for the crane to lift the concrete panel. There will be at least two eye-bolts so that the concrete panel is stable during the lifting process.
The bolt projecting from the wall is used as a fixing point for the brace which is used to hold the panel in position during construction.
Purlins are braced at right angels keeping them from over turning and to reduce the effects of lateral forces. Rods of 20mm diameter are also use to reduce the effect of these forces and carry loads to the load bearing members. Again for safety purposes, mesh is installed above the purlins which stops workers from falling through the roof members onto the ground/floor below.
Pre-cast concrete panels are used on the ground floor. The panels are constructed off site and delivered to site on a truck. Panels are manufactured by laying reinformcement in a mould followed by the concrete (concrete MPa will depend on function). Panels are lifted off the truck with the use of a crane/mobile crane.
When designed the size and location of mullions, panel legs and spandrels need to be considered both for structural purposes and transportation and lifting stresses.
An opening still remains between the two large concrete panels which start at ground level and finish at roof height. These panels are still fixed using braces as they are not fixed in position by surrounding members.
AXA / Grocon Site
I visited the AXA project which is being constructed by Grocon Constructors.
The top floor where the plant room is located is still under construction. The services on the roof are to be housed in a portal frame type structure. Concrete slabs where being installed as well as the structural elements for the frame.
The beam of this structure has cleats and brackets welded to it. These have been done off-site during the fabrication process. Other structural elements will be bolted to these brackets.
A purlin is shown which is fixed to the top of the rafters with the use of cleats. The cleats are welded to the rafters and bolted to the purlins. Safety mesh is placed on top of the purlins.
The top floor where the plant room is located is still under construction. The services on the roof are to be housed in a portal frame type structure. Concrete slabs where being installed as well as the structural elements for the frame.
Concrete is being poured to form a slab. In this photo the void barrier can be seen as well as the reinforment which is sitting on reinforment chairs. The concrete is currently beng placed and will be poured to the level of the surrounding formwork. The process of installing the slab is in this order.
This slab itself is actually a floating slab and has metal casting mounts with rubber inside (the red mounts in photo). Bolts are screwed through the metal casting into the rubber mount which then raises the slab.
Services such as generators, chillers, pumps are positioned on top of the floating floor. Having the floor raised on rubber mounts eliminates sound travelling through the building. Floating floors are used when acousitc solutions to vibration are required.
Here the slab is still being poured. Shovels are used to move the concrete around and a worker uses a piece of timber to smooth out the concrete.
The beam of this structure has cleats and brackets welded to it. These have been done off-site during the fabrication process. Other structural elements will be bolted to these brackets.
This UC column is welded to a base plate which is then fixed to a pad. Around this is 'ableflex' which is a type of material used to create isolation and construction joints. The joint created reduces/eliminates cracking. The bolts which are use to fix the column to the pad have been cast-in and are referred to as hold-down bolts.
A purlin is shown which is fixed to the top of the rafters with the use of cleats. The cleats are welded to the rafters and bolted to the purlins. Safety mesh is placed on top of the purlins.Between the purlins are braces which help when lateral forces are applied to the roof structure.
Rods are used in the roofing structure to help make it secure when lateral forces are applied.
The gap between the base plate and pad base is filled with grout. The grout is made on site and is installed usig a hand trowel.
Hold-down bolts are cast in the concrete. They pretrude long enough to take into account for the space between the concrete and base plate, the thickness of the base plate and then thickness of the bolts.
Between the base plate and the pad (plinth in this case) is a space due to the use of packers (small peices of metal used to raise the column of the pad/plinth). Using packers allows the column to to be tightened more on each bolt to level and plumb them up. Without the use of packers it would be very difficult to plumb and level columns.
Structural members are lifted with the use of a crane. Workers use scissor lifts to help position the members so that brackets and holes line up ready to be bolted together.
Rods are used in the roofing structure to help make it secure when lateral forces are applied.Where the rafter is joined a bolted splice is used. A web cleat is used to join the member.
The column and beam are joined to each other using bolts. The bolts are inserted through the plate that has been welded to the column and then through the flange of the beam.
The gap between the base plate and pad base is filled with grout. The grout is made on site and is installed usig a hand trowel.
Hold-down bolts are cast in the concrete. They pretrude long enough to take into account for the space between the concrete and base plate, the thickness of the base plate and then thickness of the bolts.
Between the base plate and the pad (plinth in this case) is a space due to the use of packers (small peices of metal used to raise the column of the pad/plinth). Using packers allows the column to to be tightened more on each bolt to level and plumb them up. Without the use of packers it would be very difficult to plumb and level columns. 
Structural members are lifted with the use of a crane. Workers use scissor lifts to help position the members so that brackets and holes line up ready to be bolted together. The steel structure which have been fabricated can be erected by the fabricators steel workers or the building may decide to have his own workers erect the structure.
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