67-520: The Dog Island Lighthouse on Dog Island in Foveaux Strait is New Zealand's tallest lighthouse, and one of its oldest. It is notable for its masonry construction, and is a work example by an engineer who was prominent at the time. The lighthouse employed the first revolving beam in New Zealand, and the unique original light apparatus was in use for 60 years. Dog Island Lighthouse is one of
134-527: A Category II structure, with registration number 2562. On 22 November 1984, the Dog Island Lighthouse was registered as a Category I structure, with registration number 395. The lighthouse is significant for its height, its age, and the relatively rare use of masonry for such a structure. It is also an example of the work of an engineer who was prominent at his time. Dog Island (New Zealand) Too Many Requests If you report this error to
201-405: A blend containing ground limestone (where a suffix L is present in the class names). White portland cement or white ordinary portland cement (WOPC) is similar to ordinary gray portland cement in all respects, except for its high degree of whiteness. Obtaining this colour requires high purity raw materials (low Fe 2 O 3 content), and some modification to the method of manufacture, among others
268-465: A construction material, concrete can be cast in almost any shape desired, and once hardened, can become a structural (load bearing) element. Concrete can be used in the construction of structural elements like panels, beams, and street furniture , or may be cast- in situ for superstructures like roads and dams. These may be supplied with concrete mixed on site, or may be provided with ' ready-mixed ' concrete made at permanent mixing sites. Portland cement
335-400: A few weeks and this causes strength growth to stop. Five types of portland cements exist, with variations of the first three according to ASTM C150. Type I portland cement is known as common or general-purpose cement. It is generally assumed unless another type is specified. It is commonly used for general construction, especially when making precast, and precast-prestressed concrete that
402-487: A fusion temperature, which is about 1,450 °C (2,640 °F) for modern cements, to sinter the materials into clinker. The materials in cement clinker are alite, belite, tricalcium aluminate , and tetracalcium alumino ferrite. The aluminium, iron, and magnesium oxides are present as a flux allowing the calcium silicates to form at a lower temperature, and contribute little to the strength. For special cements, such as low heat (LH) and sulphate resistant (SR) types, it
469-514: A given project it is best to use cement from a single batch. Bags of cement routinely have health and safety warnings printed on them, because not only is cement highly alkaline , but the setting process is also exothermic . As a result, wet cement is strongly caustic and can easily cause severe skin burns if not promptly washed off with water. Similarly, dry cement powder in contact with mucous membranes can cause severe eye or respiratory irritation. The reaction of cement dust with moisture in
536-405: A higher kiln temperature required to sinter the clinker in the absence of ferric oxides acting as a flux in normal clinker. As Fe 2 O 3 contributes to decrease the melting point of the clinker (normally 1450 °C), the white cement requires a higher sintering temperature (around 1600 °C). Because of this, it is somewhat more expensive than the grey product. The main requirement is to have
603-527: A low iron content which should be less than 0.5 wt.% expressed as Fe 2 O 3 for white cement, and less than 0.9 wt.% for off-white cement. It also helps to have the iron oxide as ferrous oxide (FeO) which is obtained via slightly reducing conditions in the kiln, i.e., operating with zero excess oxygen at the kiln exit. This gives the clinker and cement a green tinge. Other metallic oxides such as Cr 2 O 3 (green), MnO (pink), TiO 2 (white), etc., in trace content, can also give colour tinges, so for
670-633: A mild heat. The European norm EN 197-1 defines five classes of common cement that comprise portland cement as a main constituent. These classes differ from the ASTM classes. * Constituents that are permitted in portland-composite cements are artificial pozzolans (blast furnace slag (in fact a latent hydraulic binder), silica fume, and fly ashes), or natural pozzolans (siliceous or siliceous aluminous materials such as volcanic ash glasses, calcined clays and shale). The Canadian standards describe six main classes of cement, four of which can also be supplied as
737-505: A type of building stone quarried on the Isle of Portland in Dorset, England. The development of modern portland cement (sometimes called ordinary or normal portland cement) began in 1756, when John Smeaton experimented with combinations of different limestones and additives, including trass and pozzolanas , intended for the construction of a lighthouse, now known as Smeaton's Tower . In
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#1732790433767804-412: A typical concrete sets in about 6 hours and develops a compressive strength of 8 MPa in 24 hours. The strength rises to 15 MPa at 3 days, 23 MPa at 1 week, 35 MPa at 4 weeks, and 41 MPa at 3 months. In principle, the strength continues to rise slowly as long as water is available for continued hydration, but concrete is usually allowed to dry out after
871-440: A very low (C 3 A) composition which accounts for its high sulphate resistance. The maximum content of (C 3 A) allowed is 5% for type V portland cement. Another limitation is that the (C 4 AF) + 2(C 3 A) composition cannot exceed 20%. This type is used in concrete to be exposed to alkali soil and ground water sulphates which react with (C 3 A) causing disruptive expansion. It is unavailable in many places, although its use
938-543: Is immediately dangerous to life and health . Portland cement manufacture can cause environmental impacts at all stages of the process. These include emissions of airborne pollution in the form of dust; gases; noise and vibration when operating machinery and during blasting in quarries; consumption of large quantities of fuel during manufacture; release of CO 2 from the raw materials during manufacture, and damage to countryside from quarrying. Equipment to reduce dust emissions during quarrying and manufacture of cement
1005-404: Is added to the clinker, and the mixture is finely ground to form the finished cement powder. This is achieved in a cement mill . The grinding process is controlled to obtain a powder with a broad particle size range , in which typically 15% by mass consists of particles below 5 μm diameter, and 5% of particles above 45 μm. The measure of fineness usually used is the ' specific surface area ', which
1072-409: Is also used in mortars (with sand and water only), for plasters and screeds , and in grouts (cement/water mixes squeezed into gaps to consolidate foundations, road-beds, etc.). When water is mixed with portland cement, the product sets in a few hours and hardens over a period of weeks. These processes can vary widely, depending upon the mix used and the conditions of curing of the product, but
1139-457: Is common in the western United States and Canada. As with type IV, type V portland cement has mainly been supplanted by the use of ordinary cement with added ground granulated blast furnace slag or tertiary blended cements containing slag and fly ash. Types Ia , IIa , and IIIa have the same composition as types I, II, and III. The only difference is that in Ia, IIa, and IIIa, an air-entraining agent
1206-429: Is delivered to end users either in bags, or as bulk powder blown from a pressure vehicle into the customer's silo. In industrial countries, 80% or more of cement is delivered in bulk. Cement sets when mixed with water by way of a complex series of chemical reactions still only partly understood. The different constituents slowly crystallise, and the interlocking of their crystals gives cement its strength. Carbon dioxide
1273-411: Is generally known for its low heat of hydration. Its typical compound composition is: 28% (C 3 S), 49% (C 2 S), 4% (C 3 A), 12% (C 4 AF), 1.8% MgO, 1.9% (SO 3 ), 0.9% ignition loss, and 0.8% free CaO. The percentages of (C 2 S) and (C 4 AF) are relatively high and (C 3 S) and (C 3 A) are relatively low. A limitation on this type is that the maximum percentage of (C 3 A) is seven, and
1340-516: Is generally not stocked by manufacturers, but some might consider a large special order. This type of cement has not been made for many years, because portland-pozzolan cements and ground granulated blast furnace slag addition offer a cheaper and more reliable alternative. Type V is used where sulphate resistance is important. Its typical compound composition is: 38% (C 3 S), 43% (C 2 S), 4% (C 3 A), 9% (C 4 AF), 1.9% MgO, 1.8% (SO 3 ), 0.9% ignition loss, and 0.8% free CaO. This cement has
1407-468: Is grey, but white portland cement is also available. Its name is derived from its resemblance to Portland stone which is quarried on the Isle of Portland in Dorset , England. It was named by Joseph Aspdin who obtained a patent for it in 1824. His son William Aspdin is regarded as the inventor of "modern" portland cement due to his developments in the 1840s. The low cost and widespread availability of
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#17327904337671474-418: Is ground into the mix. The air-entrainment must meet the minimum and maximum optional specification found in the ASTM manual. These types are only available in the eastern United States and Canada, only on a limited basis. They are a poor approach to air-entrainment which improves resistance to freezing under low temperatures. Types II(MH) and II(MH)a have a similar composition as types II and IIa, but with
1541-452: Is heated to high temperature. The key chemical reaction distinguishing portland cement from other hydraulic limes occurs at these high temperatures (>1,300 °C (2,370 °F)) as belite (Ca 2 SiO 4 ) combines with calcium oxide (CaO) to form alite (Ca 3 SiO 5 ). Portland cement clinker is made by heating, in a cement kiln , a mixture of raw materials to a calcining temperature of above 600 °C (1,112 °F) and then
1608-478: Is in contact with soils and ground water, especially in the western United States due to the high sulphur content of the soils. Because of similar price to that of type I, type II is much used as a general purpose cement, and the majority of portland cement sold in North America meets this specification. Note: Cement meeting (among others) the specifications for types I and II has become commonly available on
1675-425: Is necessary to limit the amount of tricalcium aluminate (3 CaO·Al 2 O 3 ) formed. The major raw material for the clinker-making is usually limestone ( CaCO 3 ) mixed with a second material containing clay as source of alumino-silicate. Normally, an impure limestone which contains clay or SiO 2 is used. The CaCO 3 content of these limestones can be as low as 80%. Secondary raw materials (materials in
1742-473: Is not to be in contact with soils or ground water. The typical compound compositions of this type are: 55% (C 3 S), 19% (C 2 S), 10% (C 3 A), 7% (C 4 AF), 2.8% MgO, 2.9% (SO 3 ), 1.0% ignition loss , and 1.0% free CaO (utilizing cement chemist notation ). A limitation on the composition is that the (C 3 A) shall not exceed 15%. Type II provides moderate sulphate resistance, and gives off less heat during hydration. This type of cement costs about
1809-734: Is on display at the Museum of Wellington City & Sea on Jervois Quay in Wellington, on loan from Maritime New Zealand. The 1865 rotating mechanism can be seen at the Bluff Maritime Museum . There is no public access to Dog Island or to the lighthouse. The lighthouse is being maintained by Maritime New Zealand . The lighthouse keepers cottage was registered by the New Zealand Historic Places Trust (now Heritage New Zealand) on 24 November 1983 as
1876-520: Is remote controlled from Maritime New Zealand's Wellington office. Despite the lighthouse, the steamer SS Waikouaiti ran aground on Dog Island on 28 November 1939 during dense fog and was wrecked. Dog Island Lighthouse has twice featured on New Zealand stamps. In 1969, the New Zealand Government Life Insurance Department (better known as Government Life) issued five stamps showing lighthouses, with
1943-423: Is slowly absorbed to convert the portlandite (Ca(OH) 2 ) into insoluble calcium carbonate . After the initial setting, immersion in warm water will speed up setting. Gypsum is added as an inhibitor to prevent flash (or quick) setting. The most common use for portland cement is in the production of concrete. Concrete is a composite material consisting of aggregate ( gravel and sand ), cement, and water. As
2010-406: Is that the six-month strength of type III is the same or slightly less than that of types I and II. Therefore, the long-term strength is sacrificed. It is usually used for precast concrete manufacture, where high one-day strength allows fast turnover of molds. It may also be used in emergency construction and repairs, and construction of machine bases and gate installations. Type IV portland cement
2077-522: Is the total particle surface area of a unit mass of cement. The rate of initial reaction (up to 24 hours) of the cement on addition of water is directly proportional to the specific surface area. Typical values are 320–380 m ·kg for general purpose cements, and 450–650 m ·kg for 'rapid hardening' cements. The cement is conveyed by belt or powder pump to a silo for storage. Cement plants normally have sufficient silo space for one to 20 weeks of production, depending upon local demand cycles. The cement
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2144-476: The German Standard , issued in 1909). Clinkers make up more than 90% of the cement, along with a limited amount of calcium sulphate (CaSO 4 , which controls the set time), and up to 5% minor constituents (fillers) as allowed by various standards. Clinkers are nodules (diameters, 0.2–1.0 inch [5.1–25.4 millimetres]) of a sintered material that is produced when a raw mixture of predetermined composition
2211-572: The Invercargill Harbour Master to James Alexander Robertson Menzies , the first Superintendent of the Southland Province . The Harbour Master's rationale was that the island was dangerous, as "it is very low and not seen till close upon it". At the time, the Southland Province had just split from Otago Province , and both provincial governments were involved. There was confusion over who would take ownership of
2278-471: The London sewer project . This became a specification for portland cement. The next development in the manufacture of portland cement was the introduction of the rotary kiln , patented by Frederick Ransome in 1885 (U.K.) and 1886 (U.S.); which allowed a stronger, more homogeneous mixture and a continuous manufacturing process. The Hoffmann "endless" kiln which was said to give "perfect control over combustion"
2345-553: The Occupational Safety and Health Administration (OSHA) has set the legal limit ( permissible exposure limit ) for portland cement exposure in the workplace as 50 mppcf (million particles per cubic foot) over an 8-hour workday. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 10 mg/m total exposure and 5 mg/m respiratory exposure over an 8-hour workday. At levels of 5000 mg/m , portland cement
2412-688: The Stevensons were his brothers-in-law. The equipment arrived on the ship City Of Dunedin from Glasgow in Port Chalmers on 3 September 1863, and the light apparatus arrived via the ship Resolute on 17 March 1864. The light apparatus for the Taiaroa Head lighthouse also arrived on the Resolute . Dog Island is low-lying and rocky, and its highest (natural) point is about 15 metres (49 ft) above sea level. Calculations showed that
2479-526: The Wikimedia System Administrators, please include the details below. Request from 172.68.168.150 via cp1114 cp1114, Varnish XID 963451514 Upstream caches: cp1114 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 10:40:33 GMT Portland cement Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete , mortar , stucco , and non-specialty grout . It
2546-408: The balcony. The lantern was placed at a height of 30.5 metres (100 ft). Two dwellings, also designed by Balfour, were constructed for the lighthouse keepers and their families. The total cost came to £10,480-12s-8d, which was significantly more than the average cost of between £4,000 and £6,000 at the time. The light apparatus was specifically designed for the remoteness of the location. Instead of
2613-668: The first portland cement was produced in the Coplay Cement Company Kilns under the direction of David O. Saylor in Coplay, Pennsylvania . By the early 20th century, American-made portland cement had displaced most of the imported portland cement. ASTM C150 defines portland cement as: hydraulic cement (cement that not only hardens by reacting with water but also forms a water-resistant product) produced by pulverizing clinkers which consist essentially of hydraulic calcium silicates, usually containing one or more of
2680-581: The forms of calcium sulphate as an inter ground addition. The European Standard EN 197-1 uses the following definition: Portland cement clinker is a hydraulic material which shall consist of at least two-thirds by mass of calcium silicates , (3 CaO·SiO 2 , and 2 CaO·SiO 2 ) , the remainder consisting of aluminium- and iron-containing clinker phases and other compounds. The ratio of CaO to SiO 2 shall not be less than 2.0. The magnesium oxide content ( MgO ) shall not exceed 5.0% by mass. (The last two requirements were already set out in
2747-426: The general purpose clinker is usually used, ground to a specific surface area typically 50–80% higher. The gypsum level may also be increased a small amount. This gives the concrete using this type of cement a three-day compressive strength equal to the seven-day compressive strength of types I and II. Its seven-day compressive strength is almost equal to 28-day compressive strengths of types I and II. The only downside
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2814-740: The highest denomination (15c) depicting the Dog Island Lighthouse. In 2009, New Zealand Post issued five stamps commemorating the 150th anniversary of New Zealand's oldest lighthouse at Pencarrow Head ; the Dog Island Lighthouse was included with a $ 1 value. The lighthouse was automated in 1989, and the island has since been uninhabited. The lighthouse is the tallest lighthouse in New Zealand, and one of its oldest. Due to its black and white stripes, it might be one of New Zealand's most distinctive lighthouses. There are only two other lighthouses in New Zealand of similar appearance; Cape Campbell Lighthouse also has black and white stripes, whilst Cape Palliser Lighthouse has red and white stripes. The lens from 1925
2881-522: The kind invented 7 years later by the French engineer Louis Vicat . Vicat's cement is an artificial hydraulic lime , and is considered the "principal forerunner" of portland cement. The name portland cement is recorded in a directory published in 1823 being associated with a William Lockwood and possibly others. In his 1824 cement patent, Joseph Aspdin called his invention "portland cement" because of its resemblance to Portland stone . Aspdin's cement
2948-410: The late 18th century, Roman cement was developed and patented in 1796 by James Parker . Roman cement quickly became popular, but was largely replaced by portland cement in the 1850s. In 1811, James Frost produced a cement he called British cement. James Frost is reported to have erected a manufactory for making of an artificial cement in 1826. In 1811 Edgar Dobbs of Southwark patented a cement of
3015-435: The light was replaced again, this time with a rotating beacon, with a 35-watt halogen bulb as the light source. The energy comes from solar panels and a battery bank. A third dwelling for lighthouse keepers was built in 1884. The three original dwellings were in a poor state by the 1920s and two houses with six rooms each were built for the families; at the same time, the two original cottages became storage sheds. A new house
3082-450: The lighthouse would have to be some 110 feet (34 m) tall if built on the highest point to be effective. An investigation showed that there was enough rock that could be quarried on the island for the structure, and that it would be too expensive to build such a tall tower from steel. The tower designed by Balfour was 36 metres (118 ft) tall. It had a diameter of 6.6 metres (22 ft) at its base, and 5.0 metres (16.4 ft) below
3149-501: The limestone, shales , and other naturally occurring materials used in portland cement make it a relatively cheap building material. Its most common use is in the production of concrete, a composite material consisting of aggregate (gravel and sand), cement, and water. Portland cement was developed from natural cements made in Britain beginning in the middle of the 18th century. Its name is derived from its similarity to Portland stone ,
3216-417: The maximum percentage of (C 3 S) is thirty-five. This causes the heat given off by the hydration reaction to develop at a slower rate. Consequently, the strength of the concrete develops slowly. After one or two years the strength is higher than the other types after full curing. This cement is used for very large concrete structures, such as dams, which have a low surface to volume ratio. This type of cement
3283-559: The most distinct lighthouses in New Zealand, with only two others having stripes painted on them for better visibility at daytime. The lighthouse is registered by Heritage New Zealand as a Category I structure, and the adjacent lighthouse keepers cottage has a Category II registration. Originally operated by three lighthouse keepers, the structure has since 1989 been remote controlled from Maritime New Zealand 's Wellington office, with Dog Island since having been uninhabited. Dog Island Lighthouse has twice featured on New Zealand stamps . It
3350-423: The raw mix other than limestone) depend on the purity of the limestone. Some of the materials used are clay , shale , sand , iron ore , bauxite , fly ash , and slag . When a cement kiln is fired by coal, the ash of the coal acts as a secondary raw material. To achieve the desired setting qualities in the finished product, a quantity (2–8%, but typically 5%) of calcium sulphate (usually gypsum or anhydrite )
3417-416: The same as type I. Its typical compound composition is: 51% (C 3 S), 24% (C 2 S), 6% (C 3 A), 11% (C 4 AF), 2.9% MgO, 2.5% (SO 3 ), 0.8% ignition loss, and 1.0% free CaO. A limitation on the composition is that the (C 3 A) shall not exceed 8%, which reduces its vulnerability to sulphates. This type is for general construction exposed to moderate sulphate attack, and is meant for use when concrete
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#17327904337673484-409: The same direction would still produce a, albeit somewhat weaker, beam. The light mechanism was also reasonably simple to repair should the need arise. It was the first revolving light apparatus in New Zealand. The lighthouse was first operated on 5 August 1865. Within a year of its construction, it was noted that the tower oscillated in high winds much more than other towers. Due to weak peaty subsoils,
3551-518: The sinuses and lungs can also cause a chemical burn, as well as headaches, fatigue, and lung cancer. The production of comparatively low-alkalinity cements (pH<11) is an area of ongoing investigation. In Scandinavia , France, and the United Kingdom, the level of chromium(VI) , which is considered to be toxic and a major skin irritant, may not exceed 2 parts per million (ppm). In the US,
3618-762: The situation, and in the end, the central government assumed responsibility for the construction of all lighthouses throughout the colony. James Balfour , at the time marine engineer to the Otago Provincial Council and later to the Colonial Government of New Zealand, was commissioned during 1863 to design the lighthouse. Balfour ordered the lighthouse equipment and the light apparatus from the renowned Edinburgh lighthouse designer Alan Stevenson . Balfour had trained under Stevenson's brothers David and Thomas Stevenson . In 1848, Balfour's older sister Maggie had married Thomas Stevenson, hence
3685-469: The structure. This colour scheme has remained ever since. In 1871, a crack appeared at the base of the tower and the Marine Engineer of the day ordered immediate strengthening. This was carried out with strong hardwood and wrought iron bands. This work, significantly hindered by bad weather, cost £978-4s-3d. By 1916, it was decided that major strengthening was necessary again, as the cement grout
3752-424: The tower took on a slight lean. During storms, the tower leaked severely and it was feared that this would strengthen the mortar between the stones. Weak mortar was scraped out in 1867 and replaced with Portland cement . At the same time, the tower was painted with a large white stripe in the middle, with the remainder painted in black, both to make the tower more visible during daylight, but also to further waterproof
3819-408: The usual central burner system with one lamp, sixteen lamps were used arranged in four, each with their own mirror behind it. The lamps were mounted on a frame with a square base that completed a revolution powered by a massive clockwork every two minutes, thus achieving a beam every 30 seconds. The reason behind the arrangement was redundancy; even if one of the lamps failed, the other three pointing in
3886-406: The world market. Type III has relatively high early strength. Its typical compound composition is: 57% (C 3 S), 19% (C 2 S), 10% (C 3 A), 7% (C 4 AF), 3.0% MgO, 3.1% (SO 3 ), 0.9% ignition loss, and 1.3% free CaO. This cement is similar to type I, but ground finer. Some manufacturers make a separate clinker with higher C 3 S and/or C 3 A content, but this is increasingly rare, and
3953-467: Was a Committee of Inquiry into lighthouse automation in 1981 and the Dog Island site was one of nine sites throughout New Zealand that was to remain staffed; in this case, it was due to its remoteness, and its ability to help with search and rescue in the area. In August 1989, Dog Island was fully automated and the last permanent lighthouse keeper in New Zealand was withdrawn from service. The lighthouse
4020-446: Was built in 1979 for the by then single lighthouse keeper. There were originally three lighthouse keepers with their families on the island. The initial rotating light mechanism had to be wound up hourly, and in 1883, the principal lighthouse keeper died when he fell down the central shaft trying to attach weights to the mechanism. In 1977, the number of lighthouse keepers were reduced from two to one due to operational improvements. There
4087-471: Was clear that a lighthouse was needed in Foveaux Strait, but there were long discussions in the 1860s where to place it. Captains with local experience were asked for their opinion, and they suggested possible sites on Centre Island , Ruapuke Island , Stewart Island , Solander Islands , and Dog Island. The latter was chosen as Southland 's first site for a lighthouse; the recommendation was made by
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#17327904337674154-517: Was developed from other types of hydraulic lime in England in the early 19th century by Joseph Aspdin , and is usually made from limestone . It is a fine powder , produced by heating limestone and clay minerals in a kiln to form clinker , and then grinding the clinker with the addition of several percent (often around 5%) gypsum . Several types of portland cement are available. The most common, historically called ordinary portland cement (OPC),
4221-438: Was failing. Plans drawn up then and amended two years later saw a reinforced concrete skin of 2 feet (0.61 m) in thickness being applied to the outside up to just below the balcony, and an internal 6 inches (150 mm) reinforced concrete lining up to the fourth floor. The tower was repainted in its previous colour scheme. The burners for the lights were changed from colza oil to paraffin oil in 1876. The original system
4288-460: Was in use for 60 years, and in 1925, the optical apparatus was upgraded to a second order dioptric lens with an incandescent oil burner. This changed the light output to three flashes in quick succession every 30 seconds. A diesel electric plant was installed in 1954, and electrical operation of the beam started in October of that year. The diesel generator was replaced in 1970. In September 1999,
4355-483: Was involved in cement making. William Aspdin made what could be called "meso-portland cement" (a mix of portland cement and hydraulic lime). Isaac Charles Johnson further refined the production of "meso-portland cement" (middle stage of development), and claimed to be the real father of portland cement. In 1859, John Grant of the Metropolitan Board of Works, set out requirements for cement to be used in
4422-481: Was nothing like modern portland cement, but a first step in the development of modern portland cement, and has been called a "proto-portland cement". William Aspdin had left his father's company, to form his own cement manufactury. In the 1840s William Aspdin, apparently accidentally, produced calcium silicates which are a middle step in the development of portland cement. In 1848, William Aspdin further improved his cement. Then, in 1853, he moved to Germany, where he
4489-620: Was tested in 1860 and shown to produce a superior grade of cement. This cement was made at the Portland Cementfabrik Stern at Stettin , which was the first to use a Hoffmann kiln. The Association of German Cement Manufacturers issued a standard on portland cement in 1878. Portland cement had been imported into the United States from Germany and England , and in the 1870s and 1880s, it was being produced by Eagle Portland cement near Kalamazoo, Michigan. In 1875,
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