When Jeff Buczkiewicz of the MCAA asked me to prepare a series of articles for Masonry, he suggested I describe some of the historic sites and restoration work I have seen or been involved in over the years. After giving that some thought, I decided I could do that but there is a bigger opportunity here. While I have had some interesting experiences, you the readers have collectively had many more. So, let’s share!
My proposal is that I’ll highlight some of my masonry experiences, adventures, and projects from around the world and you can add to them! Send in your photographs and stories of great masonry sites or projects you’ve visited or projects for which you have first-hand experience. Let’s celebrate all that is masonry. Let’s tell stories; if they are true, that’s even better. You need not write a lot. Just provide a short anecdote or experience that others would find amusing, but always highlighting the positive aspects of masonry construction.
This should not be difficult. Why? Because nearly all the significant monuments and cultural sites of the world that have survived the times are masonry. So, we have a wealth of masonry structures to talk about. We can go back millennia to the Pyramids, the Parthenon, and more. Or, we can talk about all the medieval structures that still survive as well as any modern masonry.
Masonry is unique historically! The only other construction material that has some longevity is timber. The two oldest intact timber structures in the world are the Midas Tomb (c. 740 BC) in Turkey and the next oldest is likely the Buddhist temple Lhasa Jokhang in Tibet (c. 639 CE). These structures are rare for their age because timber rots or burns. Not so for masonry! So, historical masonry structures are far more numerous and have lasted much longer. Our industry has passed the test of time!
The great thing about telling these stories is that we can get them from anywhere in the world, because masonry is the most utilized construction material.
I’ll start this off with a visit to Iraq.
Unless you have been in the military in the past 15 years or emigrated from there, it’s not likely been one of your tourist destinations. That is a shame because the region is home to the land between the Tigris and Euphrates rivers and is known as one of the cradles of civilization. Within this area lies Babylonia which traces back to c. 1800 BCE. How many civilizations have controlled this region and what wonderful developments have occurred?
Modern day Iraq was created in 1920 following World War I and administered by the British Empire. It became a kingdom in 1933 and now a republic in 1958. Since the 2003 overthrow of Saddam Hussien and subsequent rise of the Islamic State, Iraq is very much divided with the government controlling the south, the Kurdistan Regional Government controlling the northwest and currently the Islamic State (ISIL) in the west.
Masonry construction is everywhere in Iraq, new and old. That’s a natural result of not having forests; there is little timber and what does exist is mostly imported.
The masonry trade is passed down from one generation to the next. OSHA and regulations don’t exist. You’d cringe watching workers walking barefoot or in sandals and climbing on bamboo scaffolding or light pipe scaffolding with no hand rails or toe boards. But, the masonry skill has been developed over years. Most of the construction is with lime mortar for new work and restoration. Sometimes cement is used in new mortar. As in many countries, new units are clay brick or tiles or concrete masonry units. Don’t expect to find an ASTM designation for any of these.
What got me to Iraq was working for The Iraqi Institute for the Conservation of Antiquities and Heritage in Erbil, Iraq. I teach repair and temporary stabilization of historic buildings to architects, engineers, conservators and managers of historic sites. Erbil provides a wealth of historic buildings to work on. Unfortunately, security concerns preclude traveling throughout the country.
Erbil is a modern city (Figure 1) and the capital of the Kurdish Regional Government in the north. However it has an historic center and many markets. In 2008, the Kurdish government teamed with the U.S. Embassy in Baghdad, and the Iraqi State Board of Antiquities and Heritage to bring experts from around the world to train Iraqi museum and heritage professionals in the preservation and conservation of their national treasures. The institute brings together Iraqi men and women, Arabs and Kurds, Muslims and Christians, Sunni and Shia—all drawn together by a shared passion for the preservation of one of the world’s oldest civilizations and home to some of mankind’s most ancient artifacts.
Let’s look at some specific projects!
Figure 2 is an aerial view of the citadel in Erbil. Designated a World Heritage Site by UNESCO in 2014, the citadel sits on an approximately 100 feet high “tell.” A tell is a manmade hill created by civilizations building over the top of previous settlements. The United Nations believes that this site has been continuously occupied since 6,000 BC or earlier. The buildings on the citadel now date to the 19th century, and primarily constructed of mud bricks and timber. There are some remnants of British concrete and steel construction in various buildings. So we have a site that’s over 8,000 years old, but the buildings on top are less than 200 years.
In 2007, the government moved out over 3,000 thousand occupants to begin a massive restoration of over 620 mud brick dwellings and commercial and religious buildings. Mud bricks are a common building material in many countries. UNESCO mandates that fired bricks be used in the restoration rather than mud bricks but their physical properties must be close to the original mud bricks. Figure 4 shows some “modern” molded, fired bricks soaking before their use because they have very high absorption (approximately 24% to 35%). Dependent upon the source of the clay, these bricks often include straw mixed in with the soil during molding to limit shrink cracking.
Restoration seems to take forever due to the cost, temperature, and humidity. More often you’ll find buildings mothballed for restoration. Figure 5 shows typical buildings in the citadel, and throughout the older parts of the city. The blue tarps are everywhere. Anything available is used for stabilization, and that’s what I teach. There’s no mistaking these for US job sites, but you do what you can to save the buildings for future repairs.
Work techniques are not exactly OSHA approved. Figure 6 shows an exterior wythe being replaced. The original mud bricks were damaged by moisture deterioration. Notice the vertical string lines for plumb control, yet no blocking or temporary piers to support the masonry above. The headering of the walls holds it all together. The new work is bedded in lime mortar.
Away from the citadel, we see the 118-foot tall Mudhafaria minaret (Figure 7) dating to c. 1190 AD. The broken off top attests to the high seismicity of the region. While the mosque was destroyed, the minaret is now a monument and was restored by a Czech firm. The bricks are baked and lime-based mortar was used in the restoration. Many minarets lean due to thermal effects on the brick.
One of the most significant minarets in Iraq has been awaiting restoration for years. The Minaret Al-Hadba (Figure 8) is in Mosul (c. 1172) and has been threatened by ISIS occupation. The 150-foot minaret is fully intact but leans over seven feet out of plumb.
The thermal leaning is only one aspect of the problems. The minaret has serious foundation problems that threaten its stability. It’s amazing that the lean has been growing since the 14th century yet masonry stills survives.
Let’s take a look at modern masonry. Construction is generally all masonry or concrete frame with masonry infill. Figure 9 shows a new home under construction on the top with a completed one on the bottom. The structures are mostly load bearing CMU with concrete beams, floors, and columns added in. Cement is used sparingly in the mortar. Notice the numerous gaps in the head and bed joints.
While this would be unacceptable in the US, Iraqi masons do this for speed of construction, but also to use the mortar gaps to key in the cement scratch coat for the parging and adhered veneer. There is no insulation used in the buildings; they work on thermal mass. The temperature was over 90 degrees F in February when these photographs were taken. Workers start early and stop about 2pm due to the heat.
Away from the war areas, there is plenty of commercial construction as well. Figure 10 shows the larger buildings are concrete frames with masonry infill; no metal stud here. Figure 11 shows one building with the CMU infill completed and parged.
If you look closely, you can see the working planking on portions of the scaffolding. There is only one plank in any location and there are no toe boards or hand rails. Workers at this building were seen standing three abreast on the one plank with no safety equipment and wearing sandals. Safety issues are a bit different in Iraq. At other sites, I did see hardhats and safety equipment.
Well, that’s our brief look at Iraqi masonry. Next issue we’ll visit the Czech Republic and some fantastic buildings in Prague.
Meanwhile, send in a masonry photograph and description from your travels. Email them to email@example.com. We’ll look at all of them and pick a few for the magazine!
Words and Photos: David Biggs, PE, SE