Article: When Does Concrete Make More Sense?

This article basically went over the conditions and scenarios when concrete construction is better to use than steel.

It states that as projects become larger than 50,000 square feet the price of concrete starts to offset tilt-up construction's fixed costs and the method of concrete construction becomes cost-competitive with a metal building. The larger the building, the more advantageous tilt-up construction becomes.

It also states that the location of a site will influence the building materials used. Depending on the rules and regulations of each area some materials may not be used. It gives an example of an area with fairly high restrictions because of closeness of the neighbouring buildings. Fire restrictions are therfore in place and steel would become an unsutable alternative.

The moble crane lifts the panel and tilts it into position over the footing on this tilt-up construction project in the Dallas / Ft. Worth, TX area. In many cases, tilt-up construction is a better - and even more economical - choice than steel buildings

Article 2: Tilt-up Construction: A General Contractor's Approach to Innovative Commercial Building Construction

www.generalcontracter.com


This article basically explains why tilt-up construction is an innovative method for building commercial facilities with amazing speed, safety, and cost benefits. It also explains the differences between tilt up and other forms of construction.

Tiltwall building's walls are created horizontally in large slabs of concrete called panels. The panels are then lifted, or tilted up, into position around the building's slab. This means the tilt-up structure's exterior wall is virtually finished when it is tilted into place.

"Tilt-up construction (also called tiltwall or tilt wall construction) has a long history, but its widespread use is a relatively new phenomenon. In spite of this, tiltwall construction is fast becoming the method of choice for constructing modern warehouses, call centers, distribution centers, retail stores, office and storage buildings and other types of industrial and commercial facilities."

This is the model put together. You can see the beam connection to the cleat and purlin. The roofing structure is also seen with the mesh, insulation and metal roof seen.

This is another pic of my model. This time you can see the metal roofing. The roofing is screwed on to the purlin, holding on the insulation and mesh.

Model

Here is a picture of my model. You can see the i beam, the cleat which is welded to the beam, the zed purlin which is bolted to the cleat, and the mesh and insulation which is held down by the roofing.

Research

The following pictures are research for the assignment. They include 3 or 4 covers of info brochures

site 6

This shows the roof structure. This is a truss system with metal roofing.

Site 6

This is a warehouse but with a timber frame. This is not as big as the previous sites, but you can still see the cleats and the purlins attached to the rafters.

site5

This is a picture of a pad footing connection to the column. A lthough the connection cant be seen, a pin base joint would be used. The slab would have been poured over the pad footing.

Site 5

Here is another pic of the knee joint connection. However in this picture you can see the downpipe which falls down from a box gutter. The box gutter must be a min width of 300mm and a min depth of 100mm.

site5

At Mitre 10 again. This is a view of the apex connection between the two rafters. This connection is bolted and sometimes welded. The zed purlins are also seen.These hold up the roofing with the sarking, mesh and insulation held together by the metal roofing, which is screwed down into the purlin.

Site Visit 5

Here is a picture of a finished portal frame. This is located at Faggs Mitre 10. You can see the column which is bolted to the rafter creating a knee joint. This knee joint transfers bending moments from the roof down into the footings. You can also see the haunching which acts as support for the rafter.

site1

This shows the view from the roof. You can see th marks where the crane would hav lifted the panels in place.

site1

This shows the connection of the pre-cast panels. You can see on the right a connection has already been made and filled, but the temporeary join is yet to be removed.

site 1

this pic shows the pre cast concrete panels being supported up. they are first craned and placed then hooked on to the supportat the panel and at the slab. when the appropriate connection between the panels and the roof and panel to panel are made the supports will be removed and the conncetion of the supports covered with concrete.

site 1

At the end of my site tour the construction manager let me look through all the various drawings of the project. These were really good to show connection details and just to see what these drawings look like and mean. here is a pic of the panel to wall connection. This shows a section and a mirrored plan and the way in which the panel is tied to the wall and all the required dimentioning.

site1

On the roof of site 1 again. Here the roofing is in different stages of construction. U can see the mesh i still being layed and the excess which still needs to be cut out.

site1

Here is a pic friom the roof of site 1 warehouse. this was interesting i thought, as the construction manager told me that these piles were driven 18 metres into the ground. They are there to provide support for a carpark which is to be lifted up as a suspended slab. The reasoning behind such a depth is the poor quality of the soil. You can see the reinforcement required and the close proximity of each support.

Site1

Here is the first site which i was showed by the construction manager. we are up on the warehouse roof and here we can see a box gutter and a parapet wall. the gutter has a straight run, is larger than the minimum 300mm width and 100mm depth, and is string enough to carry the load of us. he showed me the method of roofing connection also which was lysaght klip-lok, which klips the roof straight on to the purlin through a special connection. you are also able to see the connection between the concrete panels which were cast off site.

site 4

This is a pic of a site on the latrobe highway. I thought this was a good picture to show, as many connections can be seen. First we can see the rafter to zed purlin connection. There is a cleat holding the zed purlin up, which is welded onto the rafter. Mesh and insulation with sisalation is then layed over thye zed purlins, then the roofing is screwed down through the zed purlin. Two steel members are also bracing the sides of the rafter, helping stabilise this section.

site 3

This is a picture of another column connection to the pad footing, at a site on hope street. However this time instead of the 2 bolt pin joint base, there is a Rigid base. The difference here is that there are atleast 4 bolts holding the column and the pad footing, and these bolts are placed at a maximum distance from the centre.

site 2

The angle bracing and the column connection to the pad footing are being tightened. For the bracing, a tension range is required in order for the bracing unit to work to its maximum potential.

site 2

Here is a pic at site 2. This shows angle bracing between two columns. These bracing units are placed at 45 degrees and are placed for wind loads on the building. Bracing works in tension.

site 2

Here is a pic of another site on visisted on breakwater road. this shows the pad footing and the column connection. It is a pin joint base as there are only two bolts located in the middle on each side of the web.

Site Visit

This is a pic of a site i visited. i met up with the construction manager and he went throught the whole site with me and explained all the details of the building. Here a crane is lifting roofing and air conditioning units on top of the roof.

This picture shows the main structural components of a Portal Frame.

This is another section of a warehouse, this time cut through the centre.

This picture is a section through a warehouse showing the structural components making up the frame.

These pictures show the various components that make up a gutter.