Average time taken to place a large rock in a structure?

Hello. I want a researcher who can prepare a short report stating how long it takes, on average, to place a large, irregular-shaped rock (anything so large that a machine is needed to lift and manipulate the rock) in a structure where each rock is being deliberately placed to form a high packing density and an interlocking structure. The sorts of structures built like this are retaining walls, seawalls, breakwaters, river levees, etc. Any type of rock can be used in these structures but it's usually a hard rock like basalt or granite or one of the more dense sedimentary rocks. The common feature of the rocks is that they all have an irregular shape because they have been extracted from a quarry after blasting but have not been shaped in any way. To see an example use Google Earth to zoom in on the breakwater at Apollo Bay, Victoria, Australia and you'll notice that the deliberately placed rocks on the seaward side of the structure have a honey-comb appearance while the rocks which have been dumped have a random appearance. I don't want a report on time taken to place concrete blocks, regular-shaped blocks or blocks which have been placed by hand. If blocks of rock have mortar or grout between them then I don't want the time to apply the mortar or grout to be included in the time per block. To work out the average time a valid method would be similar to the following. Three observations are made on three separate days; Day 1 - Work packing the armour layer of a seawall starts at 0800 and 3 rocks are placed by 1000 when the workers take a break. Day 2 - From 1230 to 1600 10 rocks are packed. Day 3 - From 1030 to 1200 2 rocks are packed. So that's a total of 15 rocks in 7 hours, or 28 minutes per rock. You might be lucky enough to be living or working in sight of such a structure being built right now. If this method is used then a log of observations, details of the job (location, type of structure, contractor, type of machinery used) and photos of the job from your observation point on each of the 3 days should be included with the report. Another valid method would be to have access to industry data, either via a reputable publication or industry expert. I would like all data to be referenced to reputable publications with publication name, author, date, volume and page number quoted in the reference. Either a website link to a publicly available document or a copy of the relevant page of the document should be provided with the report. If data comes from personal communications then the name, profession, position and contact details of the source should be provided. An invalid method would be something like the following; The Apollo Bay breakwater contains 2,000 blocks of armourstone and it took 1 year to build the armour layer with workers on the job from 0800 to 1600 for 300 days of the year so that's 1.2 hours per rock. This type of analysis is not valid due to not enough detail in the observation to separated time spent directly on placing rocks and time on other aspects of the job. Placing large rocks will be much the same anywhere in the world so one good set of observations or reliable industry data from one job will be sufficient. There is also scope for observations from 2 or more places in the world so 2 or more researchers could be engaged to conduct this research. The main report should be short (1 or 2 pages), in English, easy to read, with well formatted data and in MS (Windows XP) doc format. Any observation log, photos, publication copies or supporting material will be in addition to the main report. Payment in two parts; 1st payment for report outline then 2nd payment for final report. I have two questions I would like to ask before deciding on who to do this research: 1. What sort of research have you conducted recently? 2. Can you provide me with a sample of some recent research you personally have conducted? Thank you