Sintered porous brick

MediumCurrent national standardsGB/T18968—2003The Terminology for Wall Materials stipulates that perforated bricks (Perforated brick) means: the hole rate is equal to or greater25%, The size of the hole is small and the number of bricks is large.

The concept of perforated brickMediumChina was introduced in the early 1990 s, specifically referring to the load-bearing series of multi-row hole bricks, whose hole size is relatively small. In the previous literature, porous brick(perforated brick）With hollow brick (hollow brick) MixedConfound together. For example, the first ministerial standard on porous bricks in China--JC196—75The two concepts are confused in the load-bearing hollow brick. The standard stipulatesThe hole rate of "hollow brick" must be15%Above, the porous brick (hollow brick) specifications are mainly three kinds:

KM₁:190mm×190mm×90mm; 

KP₁: 240mm×115mm×90mm;

KP₂: 240mm×180mm×115mm.

Because the concept of porous brick first appeared in English-speaking countries, suchA.B.by Selle,1911"Modern Brick Making" published by Renton in (Modern Brickmaking by Alfred B. Searle) In the book, porous (Perforated) and hollow (Hollow) to describe porous bricks and hollow bricks. The two products described in this document are shown in the figure.1.

                        (a）            (b）

Figure1     1911The name of the British perforated brick and hollow brick (a2) Perforated brick   (b2) Hollow Brick

sintered porous brick inMediumReview of the development of the country

actually inMediumcountry in1955The research and development of load-bearing porous bricks began in, which was first carried out in Doudian Brick and Tile Factory in Beijing, and was jointly developed by the Building Science Research Institute of the former Ministry of Construction and Engineering and Doudian Brick and Tile Factory of Beijing Building Materials Bureau. Since1958After the reform of wall materials was proposed in, the development of load-bearing porous bricks has begun in various places.1963Years in Beijing, Shanghai, Jiangsu, Guangdong, Xi'an and other places to take the lead in the development and small batch production of load-bearing porous brick.1964Year10After a national experience exchange meeting on load-bearing porous bricks was held in Changsha, Hunan, in January,1965years extended17The development and production of load-bearing porous bricks in provinces and cities. At that time, the specifications of load-bearing porous bricks showed a diversified development,30A variety. Since the last century60Since the middle of the s, load-bearing porous bricks have developed very rapidly in all parts of our country, among which Shanghai, Jiangsu, Xi'an, Sichuan, Guangdong and other provinces and cities have developed rapidly. Sichuan Province1975The annual production of perforated bricks (partly hollow bricks) once accounted for the total production of bricks in the province.56%.

From1963The year was successfully developed.240mm×115mm×90mmBearing porous brick after40Over the years, because this specification does not change the architectural design module and construction operation habits, the products of this specification have been widely used throughout the country until now. in the originalJC196—75In the "load-bearing hollow brick" ministerial standard (according to the current concept should be porous brick), the porous brick of this specification is namedKP1After the type, many places still call this specification of porous brick.KP₁type, the height of the brick is adopted1MThe size of the sign.KP1The size of the brick is generally175mm × 115mm × 90mmBricks account for about the total output.12.5%. At present, several hole arrangement forms of this kind of porous brick are most used in China, as shown in the figure.2.

             (a）                  (b）                  (c）

         (d）                     (e）                   (f）

Figure2    ChinaDomestic load-bearing perforated brick (KP1) Common hole arrangement

Pore rate30%, density1250kg/m3; (b2) Pore rate29%, density1171kg/m3; (c2) Pore rate31%, density1003kg/m3, thermal conductivity0.416W/m•k; (d2) Pore rate29%, density1280kg/m3, thermal conductivity0.316W/m•k; (e2) Pore rate25%, density1350kg/m3, thermal conductivity0.443W/m•k; (f2) Pore rate26.2%, density1170kg/m3.

Sintered hollow brick and hollow block

ChinaDescription of sintered hollow brick and hollow block in current national standards

MediumCurrent national standardsGB/T18968—2003The "Terminology for Wall Materials" stipulates that hollow bricks (Hollow brick) means: the hole rate is equal to or greater40%, The size of the hole is large and the number of bricks is small. Commonly used in non-load-bearing parts.

MediumCurrent national standardsGB13545—2003The "sintered hollow brick and hollow block" stipulates that clay, shale, coal gangue and fly ash are the main raw materials, which are roasted and are mainly used for hollow bricks and hollow blocks in non-load-bearing parts of buildings. The shape of hollow bricks and hollow blocks is right-angled hexahedron, and its length, width and height dimensions are390,290,240,190,180(175）、140,115,90mm. China's current standardsGB/T18968—2003The "Wall Materials Terminology" stipulates that the block (Block）-- Artificial blocks for construction, mostly rectangular hexahedrons, but also of various special shapes. One or more of the length, width or height of the main gauge in the block series is greater365,240or115They are called blocks. But the height is not more than six times the length or width, and the length is not more than three times the height.GB13545—2003The strength grade, density grade, hole arrangement and structure of hollow bricks and hollow blocks are specified in "sintered hollow bricks and hollow blocks".MU10.0,MU7.5,MU5.0,MU3.5,MU2.5of the five grades (see Table13); the bulk density is divided800Level,900Level,1000Level,1100The four grades of the grade (see table14); Hollow bricks (blocks) with qualified strength, density, weatherability and radioactive substances, according to size deviation, appearance quality, hole arrangement and structure (see Table15), full frost, lime burst, water absorption rate is divided into superior products (A), first class (B) and qualified products (C) Three quality levels.

In1981According to the rapid increase of high-rise buildings and frame buildings, the former Xi'an Brick and Tile Research Institute carried out in a timely manner.240 mm×115 mm×240mmThe trial production of non-load-bearing hollow bricks with horizontal holes and the application research of pilot buildings have achieved complete success. Because this specification does not change the building design modulus and construction operation habits, when it is used for horizontal hole masonry, because there are a row of small holes on the side surfaces of both ends and a certain area of plastering hanging ash surface, it is easy to hang ash jointing vertically on the side surfaces. In addition, such brick walls can also withstand the pulling force of expansion bolts (as shown in the figure104Mediuma), so, until today, this specification of non-load-bearing hollow brick has been widely used in many parts of the country. This specification of the hollow brick in the country around the emergence of many different hole type variants, figure4Some common hole type arrangements are listed in.

(a）                    （b）                  （c）

(d）                 （e）                       （f）

(g）                （h）                         （i）

(j）                     （k）                       （l）

(m))

Figure4    240mm×115mm×240mmCommon Hole Arrangement of Non-load-bearing Hollow Brick

(a）7Hole hollow brick, hole rate:40%, single weight:6.8kg, origin: Xi 'an; (b）15Hole hollow brick, hole rate:45%, origin: Xi 'an; (c）3Hole hollow brick, hole rate:36%, single weight:5.91kgOrigin: Shanghai; (d）3Hole hollow brick, hole rate:53%, density:790kg/m3Origin: Harbin; (e）13Hole hollow brick, hole rate:47%, density:874.5kg/m3, equivalent thermal conductivity:0.399W/(m•k), origin: Baotou, Inner Mongolia; (f）6Hole hollow brick, hole rate:52%Origin: Sichuan; (g）8Hole hollow brick, hole rate:50%, density:830kg/m3Origin: Harbin; (h）12Hole hollow brick, hole rate:48%, density:950kg/m3, origin: Anhui Feixi; (i）15Hole hollow brick, hole rate:48%, density:950kg/m3, origin: Anhui Feixi; (j）13Hole hollow brick, hole rate:40.3%, density:1015kg/m3, equivalent thermal conductivity:0.495W/(m•k), origin: Beijing; (k）17Hole hollow brick, hole rate:44%, single weight:5.99kg, origin: Xi 'an; (l）20Hole hollow brick, hole rate:40.2%, single weight:6.32kg, origin: Xi 'an; (m）18Hole hollow brick, hole rate:50%, single weight:5.8kgOrigin: Chongqing.

in entering2000YearAfter that, Zhejiang Terra Building Materials Co., Ltd. took the lead in introducing advanced hollow brick and hollow block production lines in Western Europe. The raw material used in this production line is shale, and the main specifications of the products produced are:290mm×240mm×190mm;290mm×240mm×115mm;290mm×240mm×90mmThree and the corresponding auxiliary supporting specifications. See the picture of the products produced by Zhejiang Terra Building Materials Co., Ltd.5.

(a）

(b）

(c）

Figure5 Hollow bricks and hollow blocks produced by Zhejiang Terra Building Materials Co., Ltd.

(a）290mm × 240mm × 190mmSeries hollow block, hole rate:60%Compressive strength:6.6MPa, density:840kg/m3Mainly used for masonry240mmand190mmWall; (b）290mm × 240mm ×115mmSeries hollow brick, hole rate:60%Compressive strength:6.4MPa, density:907kg/m3Mainly used for masonry240mmand120mmWall; (c）290mm × 240mm ×90mmSeries hollow brick, hole rate:54%Compressive strength:6.6MPa, density:949kg/m3Mainly used for masonry240mm,180mmand90mmThe wall.

InternationalHole type and main performance index of sintered hollow brick and hollow block

For non-load-bearing hollow bricks built in the horizontal hole direction, the first consideration in the hole design is to meet the requirements of vertical mortar joints that are easy to hang ash and point joints. Secondly, it must be considered that the expansion bolts can be held and wrapped on the side wall to meet the requirements of the tension of the expansion bolts. In some places, in order to meet the above requirements, the outer wall of this type of non-load-bearing hollow brick is thickened25mmOr above, increasing the density of hollow bricks, such a practice is completely unnecessary. To better illustrate this situation, Fig.6   A schematic diagram of the hole design of this kind of hollow brick (block) in Germany is given.

Non-load-bearing masonry in the direction of the above three types of horizontal holes(load bearing)Hollow Bricks (Masonry),aandbThe two types are plastered on the entire opening surface only on part of the area on both sides, and require that the plastering area of non-load-bearing hollow blocks (bricks) with horizontal holes must be greater60mm; andcThe whole opening surface can be used as the horizontal hole non-load-bearing hollow brick of the plastering surface. In regular design, it is required that the sum of the cross-sectional areas (I. e. solid cross-sectional area) of the vertical and horizontal inner ribs and outer walls of the horizontal hole non-load-bearing hollow block (brick) is greater15%, also limit the width of any hole shall not be greater40mm. The length of holes in the plastering area cannot be greater85mm, the width cannot be greater15mm.

Figure6   German horizontal hole non-load bearing(load bearing)Hole pattern design and plastering area of hollow brick (block)

( a2) Non-load-bearing hollow block (brick) with horizontal hole with single row of holes in the plastering area; (b2) Non-load-bearing hollow block (brick) with horizontal hole with single row of holes in the plastering area; (c2) Non-load-bearing hollow brick with horizontal holes that can be plastered on the whole opening surface. The number represents the data used for load-bearing.

In Europe, hollow bricks and blocks with horizontal holes have different requirements between load-bearing and non-load-bearing only in the thickness of the inner rib and the thickness of the outer wall. For example, for load-bearing hollow bricks (blocks) with horizontal holes, in order to ensure that the bricks (blocks) have sufficient strength, the thickness of the outer wall of the bricks (blocks) is required to be greater than or equal15mm, the thickness of the inner rib is greater than or equal10mm(Fig.106with asterisk data in). These data can also meet the requirements of holding the expansion bolt. The German standard is still used as an example. German StandardsDIN105The fifth part of "wall brick" includes lightweight horizontal hole hollow brick, hollow block. The use of lightweight horizontal hole hollow bricks and hollow blocks in this standard is specified to be used on load-bearing and non-load-bearing building walls. The maximum density of lightweight horizontal hole hollow brick and hollow block is specified1000kg/m3.