Vol-II Brickwork
Transcription
Vol-II Brickwork
BRICKWORK SPECIFICATIONS 91 .. 92 CONTENTS Measurements TILE WORK MOULDING TREMINOLOGY Dimensions BRICK Mortar Flat Rate HONEYCOMB Measurement Classifications Oassification Joints Circular HALF JOINING Measurements Arches BRICK WORK Arches OLD AND WORK BRICK BRICK CORNICES WORK WORK WITH NEW BRICK WORK IN ARCHES Ra~ MeaSurement BRICKSrfiles (General) Laying Sampling Soaking Scaffolding Curing of & Bricks Tests Centring and Shuttering 10-4/CPWD/ND/9r 135 144 145 150 147 148 150 151 152 140 141 139 148 149 J50 151 137 138 Page 68.1 Cornices 152 6.8.2 Corbelling 152 6.8.3 Curing and Protections 152 Measurements 152 6.8,.5 Rate 152 6.9 BRICK WORK UNDER WATER 6.10 Exposed Brick work 153 6.10.1 153 6.10.2 Facing bricks Dimensions and Tolerances 6.10.3 Sampling 153 6.10.4 Physical requirements 153 6.10.5 Joints 153 6.10.6 Scaffolding and curing 153 6.10.7 Measurements 153 6.10.8 Rate 153 6.11 Cavity walls 153 6.11.1 Metal ties 154 6.11.2 Bounding Units 154 6.11.3 Spacing 154 6.11.4 Restrictions 154 6.11.5 Measurements 154 '·6.8.4 & FOUL CONDITIONS 152 153 8. Rate 154 Appendix - A Tolerance of Bricks and Tiles 155 Appendix - B Test for Compressive Strength 156 I, 157 Appendix - C Test for Water Absmption Appendix - D Efflorescence 158 Fig. 0.1 Brick Work 159 Fig. 0.2 Brick Pillars 160 Fig. 0.3 Brick Bonds 161 Fig. 0.4 Brick Bonds (Contd.) 162 Fig. O.5.Brick Work In Arches .. 163 164 to 166 Fig 0.6 Brickwork in Cavity walls 136 Chapter - 6 List of Mandatory Tests , absorption and 159. Procedure Test Tiles for Bricks/Brick to Material Test Oaus~ ofdimensions material .& 6.1.3. 6.1.3.6 Frequency Field/laboratory Minimum A,B,C, Qty. Defflorescence 155, & 156 ofTable testing Laboratory As Appendix per 3 and 4 Page 157 Testing of , out test water BRICK WORK List ofBureau of Indian Standards Code:! 1. 712-1984 Specification for builmng lime 2. 1077-1986 Specification for common burnt clay builmng bricks. 3. 1200 (pt.III) - 1976 Method of measurements of brick work 4.2212-1962 Code of practice for brick work 5.3102-1971 Classification of burnt clay solid bricks 6. 3495-(pts i-ivy - 1976 Method of test for day builmng bricks 7.3812-1981 Specification for fly ash for use as pozzolana and·admixture. 8.5454-1978 Methods of sampling of clay building bricks. 9. 12894-1990 F1y ash-lime bricks 138 6. BRICK WORK Indenting The leaving recesses into which future work can be bonded. 6.0 TERIVHNOLOGY , . Jamb Bond The part of the wall at the side of an opening. The arrangement of the bricks in successive courses to tic the brick work together both longitudinally and transversely. The arrangement is usually designed 'to ensure that no vertical joim of one course is exactly over the one in the next course above or below it, fu.'1d there is greatest possible amount of lap. Joint \ A junction of bricks. Jointing TIle operation of finishing joints as' the ma- sonry work proceeds. Pier Bed Joint Horizontal joint in brick 'I}/Ork A tl1ickened section forming integral part of the or masonry wall placed at intervals along the wan primarily to increase the stiffiness of the wallar to carry a vertical concentrated load. The thickness of a pier is the over aU thickness including the tl1ickness of the wall, or when bonded into one leaf of a cavity wall the thickness obtained by treating this leaf as an independent wall (see fig. (lA, IB) Closer Any portion of a brick used in constructiJ1g a wall, to dose up the bond next to the end brick of a course (See Fig. 3). Coping or weathering The:cover applied over or the geometrical form given to a part of structure to enable it to shed rain water. Pillar CorbeJ :- A cantilever projecting from the face of a wall to form a bearing see Fig 1D. Cornice Horizontal or ornamental feature projecting from the face of a wall(see Fig. ID). Quoin Course An extemal comer in brick work, the term may also denote the brick used to fonn the quoin. A layer of bricks including bed mortar. Cross joint Scaffolding A joint other than a bed joint normal to the wan face. Efflorescence , Pillar means a detached masonry support. This can be rectangular, circular, elliptical etc. In case of rectangular pillar, the breadth shall not exceed three times the thickness and thickness itself shall not exceed more than thrice t.~e length of brick (See fig. IC). A temporary erection of timber or steel work used in the construction, alteration, demohtion or repairs of a building to support or to attend of the hoisting or lowering of workmen, their tools and materials. . A powdery incrnstment of salts left by evaporation~ This may be visible on tlle surface or may be below surface. In the latter case, tins is termed as crypto Efflorescence. Sill A brick work form ing the lower boundary of door or window opening (see fig. 1D) Header A brick laid with its. length across tl1.ewall. 139 Spandrel mm width and 10 to 20 mm deep on one onts flat side. The shape and size. of the . frog shall conform to IS: 12894-1990 The space between the haunches arid the road decking of an arch. Fly Ash: Fly ash shall conform to grade lor Grade 20fIS : 3812-1981. Strecher :- A brick laid with its length in the direction of the wall Bottom ash used as replacement of sand shall not have more than 12% loss on ignition when tested. String course A horizontal course projecting. from a wall usually introduced at every floor level or windows or below parapet for impartingarchitectural appearance to the structure and also kee{}7 ing off the rain water. (see fig. ID). Sand: Deleterious materials, such as clay and silt in the sand shall perferabl y be less than 5%. Templet Lime : Lime shall conform to class 'C' A pattern' of sheet metal used as a guide for setting out specific section and shape. hydrated lime of IS:712-1984. Additives; Any suitable additive considered not deterimental to the durability of bricks may be used. Toothing Bricks left projecting in alternate courses to bond with future work. c) Clay Fly Ash Bricks: The clay fly ash brick shall be sound, compact and uniform in shape and colour. Bricks' shall have smooth rectangular faces with sharp and square comers. The bricks shall be free from visible cracks, flaws, warpage, nodules of free lime and organic matter, The bricks shall be hand or machine moulded. The bricks shall have frog of 100 mm in length 40 mm width and 10 to 20 mm deep on one of its flat sides. d) Fly ash shall conform to grade I or grade II ofIS: 3812-1981. Wall joint A joint parrallel to the wall face. 6.1 Bricks/Brick Tiles/Brick bats. Bricks used in the masonry may be of the following type. a) b) Common burnt clay bricks: Shall be hand . moulded ormachine moulded. They shall be free from nodules of free lime, visible cracks, flaws warpage and organic matter, have a frog 100 mm in length 40 mm in wjdth and 10 mm to 20mm deep on one of its flat sides. Bricks made by extrusion process and brick tiles may not be provided with frogs. Each briGk shall. be marked (in the frog where provided) with the manufacturers identification mark or initials. Calcium Silicate Bricks: Calcium silicate bricks shall be sound, compact and uniform in shape-Bricks shall be free from visible cracks, warpage organic matter, large pebbles and nodules of free lime. Bricks shall be solid and with or without frog. The bricks shall be made of finely grounded sand silicious rock and lime.In addition limited quantity of fly ash conforming to IS:3812-1981 may be used in the mix. Fly ash lime brick: shall be sound, compact and uniform in shape free froIl).visible cracks, warpages flaws an~ organic matter, have a frog 100 mm in length, 40 e) 140 . Tile Brick: The bricks of 4 cm height shall be moulded without frogs. Where modular tiles are not freely available in the market, the tile bricks ofF.P .S. thickness 44 mm (1-3/4") shall be used unless otherwise specified.' t) 6.1.1 Dimensions: The bricldmay be modular or non-modular. Sizes for both types of bricks/tiles shall be as per Table 1.While use of modular bricks/tiles is recommended, non modular (FPS) bricks/titles c~ also be used where so specified: Non-modular bricks /tiles of sizes other than the sizes mentioned in Table Brick Bats: Brick bats shall be obtained from well burnt bricks. I may also be used where specified. I mm ' Actual 225x11lx44mm 225x1 190x90x4Omm 190x90x9Omm Size 1x7Omm 229xl14x44mm 200x 2oox1oox40mm 229x114x7Omm Nominal 1OOX Table Size 1OOmm 1 6.1.2 Classification: Bricks(Bricktilesshali be classified on the basis .of their minimum compressive strength as given below. Table 2 Class Designation Average compressiv~ strength Not less than Less than N/mm2 (Kgf/cm2) (100) 12.5 125 7.5 ~ (75) 10 100 5(50) .5 (50) 7.5 75 3.5(35) 3.5 (35) 5.0 50 N/mm2 (Kgf/cm2) 10(100) 10 7.5(75) ~ i TIle bricks shall have smooth rectangular faces with sharp comer and shall be uniform in colour and emjt clear ringing soUnd when struck .. in accordanCe with appendix B on Page 156) (Note: Upper limit~ specified in Table 2 are for calculatip.g the average compressive strength a) Dimensional tolerance. b) Water absorption. 6.1.3 Sampling and Tests: Samples of bricks shall be subjected to the following tests: 141 c) Efflorescence. d) Compressive strength. Scale of sampling arid criteria for conformity for visual and dimensional characteristics .- . 6.1.3:1. Sampling: For carrying out compressive strength, water absorption, efflorescence and dimensional tests, the samples of bricks shall be taken at random according to the size oflot as given in table 3 below. The sample thus taken shall be stored in a dry place until tests are made. For the purpose of sampling, the following definition shall apply. a) . Visual characteristics be selected and inspected,for ascertaining their conformity to L~erequirements of " the relevant s-pecification. The number of bricks to be selected from a lot shall depend on the size of lot and shall be in accordance of coLl and"2 of Table 3 for visual characteristics· in all cases and dimensional characteristics if Lot: a collection of bricks of same class and size, manufactured under relaltively similar conditions of production. For the purpose of sampling a lot shall contain a maximum. of 50,000 bricks. specified for individual bricks. Visual characteristics:A11 the bricks selected above in accordance with coLI and 2 afTables 3 shall be examined for visual characteristics. If the number of defective In case a consignment has bricks more than 50000 of the same classification and bricks found in the sample is less than or equal to the corresponding number as specified ill col. 3 of table 3 the lot shall be considered as satisfying the requirements of visual characteristics, otherwise the lot shall be deemed as not having met the visual requirements. size and manufactured und~r relatively similar conditions of production,it shall be divided into lots of 50,000 bricks or part there of. b) c) Sample: A collection of bricks seiected -for inspection and/or testing from a lot to reach the decision regarding th.e acceptance or rejection of the lot. ill) Defective: A brick failing to meet one or more of the specified requirements. I!.. 6.1.3~2The samples shall be taken as below: . i) ; The bricks shall Sampling from a stack: When it is necessary to take a sample from a stack, the stack shall be :divided into a number of rc:>J. or imaginary sections and t.iJ.ere- _ quired number of bricks drawn from each section. For this purpose bricks inthe upper layers of the stack shall be removed to e~able units to be sampled from places within the stack. Note: For other methods of sampling i.e. s<1"'npl1ngin motion and sampling from . lorries or trucks, IS: 5454-1978 may be refencd. 142 Dimensional characteristics: The num- ber of bricks to be selected for inspecting the dimensions and tolerance shall be in accordance \Vith col. 1 and 4 of table 3. These bricks will be divided into.igroups of 20 blicks at random .and each of tJ}e group of 20 bricks thus fonn~d will be tested for all the dimensions" and tolerances. A lot shall be considered havi.'1g found meeting the requirements of dimensions and tolerance "if none of the groups of bricks inspected fails to meet the specified requirements. Table 3 Scale of sampling and permissible istics No. of bricks in the lot number of defectives for visual and dimension~l For dimensional characteristics For characteristics specified for individual bricks for group of 20 bricks-No. of bricks to be selected. 480in 40 defective Permissible no.of 321 sample .60 the No. of - bricks to selected be character~ 2 1 2001-10000 10001-35000 . 35001-50000 Note: In case the lot contains.2000 or less bricks the sampling shall be as per decision of the Engineerin-charge. / iv) as specified in relevant material specification. The bricks for this purpose shall be taken at random from-those already selected above. 'The number of bricks to be selected for each of these characteristics shall be in accordance with relevant columns of table 4. Scale'of saIl1pling and criteria for physical characteristics The lot which has been found s~tisfactory in respect of visual and dim~nsional requirements shall be pext tested for physical characteristics like co~pressive strength, water absorption, efi1oresce~ce Table 4 Scale 0 f sampling for' physical characteristics Lot size Sample size for compressive strength, w&ter absorption and efflorScence 1 2001 - 10000 10001 - 35000 35001 - 50000 Permissible No. of defectives ' for effloiscence 3 a 2 '5 10 o .J 1 1- Note: In case the lot contains·20CO.or less bricks,the sa.TI\plingshall be as per decision of Engineer -in-charge. 143 v) Brick tiles: A lot shall be considered having satisfied the requirments of physical characteristics if the condition stipulated here in are all satisfied. a) 76 to 84 cm (80 ± 4).for 40 mm high brick tiles In case of non modular bricks, % age tolerance will be ±2% for group of 20 numbers of class. 10 bricks, and ± 4% for other class of bricks. From the test results for compressive strength, the average shall be calculated and shall satisfy the requirements specified in relevant material specification. 6.1.3.4. Compressive strength: The bricks. when tested in accordance with the procedure laid down in appendix B on page 156 shall have a minimum average compressive strength' for variouss classes as given in Table 2. The compressive strength of any individual brick tested shall not fall below the min. average compressive strength spacified.for the corresponding class of brick by more than 20%. In case compressive strength of any individual brick tested exceeds the upper limit specified in table 2 for the corresponding class .of bricks, the same shall be limited to upper limit of the class as specified in Table 2 for the purpose of calculating the average'compressive strength. Note:In case any .of the test results for compressive strength exceeds the . upper limit for the class of bricks, - the same shall be limited to the upper limit of the class for the purpose of averaging. b) c) d) Wherever specified in the material specification, the compressive strength of any individual bricks tested in the sample shall not fall below the minimum average compressive strength specified for the corresponding class of brick by more. than 20 percent. 6.1.3.5 Water absorption: The average wa.ler absorption of bricks when tested in accordance with the procedure laid down in appendix C on page 157 shall be not more than 20% by weight. From the test results for water absorption, the average for the bricks in the sample shall be calculated and shall satisfy the relevant re:" quirements specification in mate~ rial specification. 6.1.3.6 Efflorescence : The rating of efflorescence of bricks when tested in accordance. with the procedure laid down in appendixD on page 158 shall be not more than Moderate. The ~umber of bricks failing to satisfy the requirements of the efflorescence specified in the relevant specification should not be more than the permissible no. of defectives given in co!. 3 of table 4 . 6.2 BRICK WORK 6.2.1 Classification: The brick work shall .be classified according to the class designation of bricks used. 6.1.3.3 Dimensional tolerances: The dimensions of, modular bricks when tested as described above as per procedure described in appendix A on page 155 shall be within the following limits per 20 bricks. 6.2.2 Mortar: The mortar for the brick work shall be as specified, and conform to accepted standards. Lime shall not be used where reinforcement is provided'in brick work. Length 372 to 388 cm (380±8cm) . 6.2.3 Soaking of Bricks: Bricks shall be soaked in water before use for· a period for the water to just penetrate-the whole depth· of the bricks. Alternatively bricks may be adequately Width 176 to 184 cm (180 ± 4cm) Height 176 to 184 cm (180 ± 4cm) for 90 mm high bricks) 144 soaked in stacks by profusely spraying with clean water at regular intervals for a period not less than six hours. The bricks required for masonry work using mud mortar shall not be soaked. When the bricks are soaked they shall be Jemoved from the tank sufficiently early so that at tQ.etime of laYing they are skin-dry. Such soaked bricks shall be stacked on a clean erly bedded and set in position by gently pressing with the handle of a trowel. Its inside face shall be 'buttered with mortar before the next brick is laid and pressed against it. Joints shall be fully filled and packed with mortar such that .no hollow space are·l~ft inside the joints. ~ 6.2.4.3 The walls shall be taken up truly in plumb or true to the required batter where specified. All courses shall be laid truly horizontal and all vertical joints shall be truly vertical. Vertical joints in the alternate course shall come directly one over the other. Quoin, Jambs and other angles shall be properly, plumbed as the work proceeds. C'are shall be taken to keep the perpends properly aligned within following maximum permissible tolerances. place where they are not again spoiled by dirt earth. etc. NoteI: The period of soaking may be easily found at site by a field test in which the bricks are soaked in water for different periods and then broken to find the extent of water penetration. The least period that corresponds to complete soaking will be the one to be allowed for in construction work. Note II : If the bricks are soaked for the a) Deviation from vertical within a storey shall not exceed 6mm per 3m height. b) Deviation in verticality in total height of any wall of building more than one storey in height shall not exceed 12.5mm. c) Deviation from position shown on plan of any brick work shall not exceed 12.5mm. not be used except as closer where necessary to complete the bond. Closers in such CJlses,shall be cut to the required size and used near the ends of the waU. Header bond shall be used d) Relative displacement between load bear" ing wall in adjacent storeys intended to be .vertical alignments shall npt exceed 6mm. preferably in all courses in curved plan for ensuring better alignment. e) A set of tools comprising of wooden straight edge, masonic spirit levels, square, I meter rule line and plumb shall be kept on the site of work for every 3 masons for proper check during the progress of ~ork. required time in water that is frequently chang~d the soluble salt in the bricks will be leached out, and subsequently efflorscence will be reduced. 6.2.4 Laying 6.2.4.1 Bricks shall be laid in English Bond (Fig. 2, 3,4) unless otherwise specified. For brick work in half brick wall, bricks shall be laid in stretcher bond. Half or cut bricks shall Note : Header bond shall also be used in foundation footings unless thickness of walls (width of footing) makes the use of headers impracticable. Where thickness of footing is uniform for a number of courses, the top course of footing shall be headers. 6.2.4.4. All quoins shall be accurately constructed and the height of brick courses shall be kept uniform. This will be checked using graduated wooden straight edge or storey rod indicating height of each course including thickness of joints. The position of damp proof course, window sills, bottom of lintels, top of the wall etc. along the height of the wall shall be marked on the graduated straight edge or 6.2.4.2 All loose materials, dirt and set lumps of mortar which may be lying over the surface on which brick work is to be freshly started, shall be removed with a wire brush and surface . wetted. BIicks shall be laid on a full bed of mortar. when laying, each brick shall, be prop- 145 storey rod. Acute and obtuse quoins shall be bonded, where practicable in the same way as square quoins. Obtuse quoins shall be fonned with squint showing three quarters brick on one face and quarter brick on the other.' thick, both the faces shall be kept even and in proper plane. 6.2.4.10 To facilitate taking service lines later without excessive cutting of compltoted work, sleeves (to be paid separately) shilll be: provided, where specified, while raising the brick work. Such sleeves in external walls shall be . sloped down outward so as to avoid passage of water inside. 6.2.4.5 TIle brick vt'Ork shall be built in uniform layers. No part of the waU during it.sconstmction shall rise more than one metre. above the general construction level. Parts of wallieit at different 6.2.4.11 Top of the brickwork h'1 coping ,Ind' sills in external walls shall be slightly tilted. Where brick coping and sins are projecting le.vels shall be raked back at an angle of 45 degrees or less with the horizontal. Toothing shaH not be permitted as an alternative to nikihg back. For ha.1fbrick partition to be keyed into main walls, indents shall be left in the main walls. beyond the face of the wall, drip course/ throating (to tx~paid separately) shall tx: provided where indicated. 6.2.4.12 Care .shall be taken during construction that edges of jamb:;, sills a..ndprojections 6.2.4.6 An pipe fittings and specials, spouts, hold fasL<; and other fixtures \vhich are required to be bui!finto the walls shall be embedded, as specified, LJ1theircolTect position as tl!C work proceeds unless otherwise directed by the EngjI!eer-in~charge. are not damaged in case of rai.n. New built work shall be covered with gunny bags or tarpouIin so a:- to prevent the mortar from being washed away. Damage, if any, shaH be made goed to the satisfaction of the engineer-in-charge. 6.2.4.13 Vertical reinforcement in the form of 6.2.4.7 Top course~~ uf all plinths, parapets, steps and top of walls below floor and roof slabs shall be laid willI brick on edge, unless specified otherwise. Brick on edge laid in the top courses at comer of walls shall be pmperl y radiated and keyed into position to form cui: (mam) comers as shown in fig.4. ¥lhcre bricks cannot ~ cut to the required shape to form cut (!Darn) comers; cement concrete 1:2:4 (1 cement:2 coarse sand: 4 graded stone aggregate 20 mm nominal size) equal to thickness of course shan be provided in·lieu of cut bricks. bars (MS or high strength deformed bars), considered necessary at the cDmers a~d june·· lion of walls and ja.'1l b opening doors, \vindows etc. shall be encased with cement mortar not leaner than 1:4 (1 cement: 4 coarse sand). or cement concrete mix as specified. The reinforcement shall b-~ suitably tied, properly embedded in the foundation and afrooflevcl. The dia. of bars shall not ~ less than 8rom and concrete grade shall be minimum 1:3:6. (1 cement: 3 coarse sand: 6 graded stone aggregate 20mm nominal size) 6.2.4.8 Bricks shall be laid \Vitll fTOg(where provided) up. However when top course is exposed, bricks shall he laid with frog down. FOi the bricks to be laid with frog down, the frog shall be filled with mortar before placing the brick in position. 6.2.4.14 In retaining walls and t~e Jik~,wherewateris likely to accuITI_u1ate,wcepholes, 50 to 75mm squ~reshallbe provided at 2m vertically and horizontally unless otherwise spr;cified. 'The lowest weep hole shall be at about 30cm above me ground level. All weep holes shall be surrounded by loose stones and shall have sufficient fan to drain out the ,?/atcr quickly (Note: work of providing loose stone will be payable extra). 6.2.4.9 In case of:w«]ls one brick thick and under, one face shall be kept even and in proper plane, while the other face may be slightly rough. In case of walls more than one brick 146 6.2.4.15 Work of Gutting chases, wherever required to be made in the walls for housing G.1. pipe, CI pipe or any other fixtures shall be carried out in various'locations as per guidelines given below:(a) vi) Cutting of chases L.'1lK:.C brick thick and . above load bearing walls. i) li) As far as possible services should be planned with the help of vertical chases. Horizontal chases should be avoided. (b) When narrow stretches of masonry (Or short lenghts of walls) such as between doors and windows, cannot be avoided they should not be pierced with openings for soil pipes or waste pipes or timbe.r joints, etc. Where there is a possibility ofload concentration such narrow lengths . of walls shall be checked for stresses (c) be provided only when unavoidable. 6.2.5.0 Joints The thickness of all types of of joints including brick wall joints and crossjoi~ts shall be such that four course and three joints taken consecutively shall measure as follows- Horizontal chases when unavoidable should be lo~ated in the upper or lower one third ofheig~t of storey and not more than three chases should be permitted in any stretch of a wall. No continuous horizontal chase shall exceed one metre in length. Where unavoidable, stresses in the affected area should be checked and kept within the permissible limits. v) Cutting of chases in half brick non load bearing wall:Services should be planned with the help of vertical chases. Horizontakhase should and high strength bricks in mortar or concrete walls provided, if required. iv) Cutting of chases in half brick load bearing walls: No chase shall be perrnitted in half brick load beari.ng waH:; and as such no reccessed conduits and concealed pipes shall be provided with half brick thick load bearing walls . The depths of vertical chases and horizontal chases shall not exceed one third and one sixth of the Lhickness of the masonry respectively. .ill) Mason.ry directly above a recess, if wider than 30cm horizontal dim en.. sian) should be supported on lintel. Holes in masonry may be provided upto 30cm width and 30cm height without aily lintel. In the case of circular holes in the masonry, no lintel need be provided for holes upto 40cm in diameter. (i) In case of Modular bricks conforming to IS: 1077 -1986 specification for common burin clay buildings bricks, equal to 39 cm (ii) In case of non modular bricks, it shall be equal to 31em. Note: Specified thickness of joints shall be of 1crn Deviation from the specified thickness of all joints shall not exceed one fifth of specified thickness . V~rtical chases should not be closer . than 2m in any stretch of a wall., These shall be kept away from bearings of beams and lintels. If unavoidable, stresses in the affected area should be checked and kept within permissible limits. 6.2.5.1 Finishing of joints The face of brick work may be finished flush or by pointing. In flush finishing either the face joints of the mortar shall be worked oMtwhile 147 still green to give a finished surface flush with etc. double scoffolding having two independent supports, clear of the work, shall be provided. the face of the brick work or the joints shall be squarely raked out to a depth of 1 cm while the mortar is still green for subsequently plastering. The faces of brick work shall be cleaned with wire brush so as to remove any splashes of mortar during the course of raising the brickwork. In pointing, the joints shall be squarely raked out to a depth of 1.5cm while the mortar is still green and raked joints shall be brushed to remove dust and loose particles and well wetted, and shall be later refilled with mortar to give ruled finish. Some such finishes are 'flush' .weathered' , ruled, etc. 6.2.8 Measurements 6.2.8.1 Brick work shall be measured in cubic metres unless otherwise specified-. Any extra work over the specified dimensions shall be ignored. Dimensions shall be measured correct to the nearest O.Olm i.e. lcm. Areas shall be calculated to the nearest 0.01 sqmtrs and tI'1e . cubic contents shall be worked out to the nearest 0.01 cubic metres . 6.2.8.2 Brick work shall be measured separately in the following stages: 6.2.6 Curing: The brick work shall be constantly kept moi~t on all faces for a minimum period of seven days,Brick work done during the day shall be suitably marked indicating the date on which the workis done so as to keep a watch on the curing period. 6.2.7. Scaffolding: Scaffolding shall be strong to withstand all dead, live and impact loads which are likely to come on them. Scaffolding shall be provided to allow easy approach to every part of the work. (a) From foundation to floor one level (plinth level) (b) Pli':lth (floor one) level to floor two level (c) Between two specified floor levels above floor two level . Note: i) Brick work in parapet walls, mumty, lift machine room and water tanks constructed on the roof upto 1.2m height above roof shall be measured together with the corresponding work of the floor next below: 6.2.7.1. Single Scaffolding Where plastering, pointing or any other finishing has been indicated for brick work, single scaffolding may be provided, unless otherwise specified. In single scaffolding, one end of the put-logs/pole shall rest in the hole provided in the header course of brick masonry. Not more than one header for each put-log/pole shall be left out. Such holes shall not be allowed in the 6.2.8.3 No deductions or additions shall be done and no extra payment made for the following- case of pillars, brick work less than one metre in length between the operungs or near the skew backs of arches or immeiliately under or near the structural member supported by the walls. The holes left for put-logs/poles shall be made good with brick work and wall finishing as specified. a) Ends ofdissimilarmaterials{that is, joists, beams, lintels, posts, girders, rafters, purlins, trusses, corbels, steps, etc.); up to 0.lm2 in section; b) Opening up to 0.lm2 in area (see Note); c) Wall plates, bed plates, and bearing of slabs, chajjas and the like, where thickness does not exceed. 10em and bearing does not extend over the full thickness of wall; 6.2.7;2 Note: Where minimum area is defined for deduction of an opening, void or both, such areas shall refer only to opening or void within the space measured. Double scaffolding: Where the brick work or tile work is to be expo1'~d and not to be finished with plastering 148 d) Cement concrete blocks as for hold fasts and holding down bolts; e) Iron fixtures, such as wall ties, pipes upto 300mm diameter and hold fasts for doors and windows; and f) Chases of section not exceeding 50cm in girth. g) Bearing portion of drip course, bearing of moulding and cornice. and shall include all cutting and wastage of bricks, tapered vertical joints and use of extra mortar, if any, Brick work curved on plan to a mean radius not exceeding six metres shall be measured separately and extra shall be payable over the rates for brick work, in straight walls. Nothing extra shall be payable if the mean . radius of the brick work curved in plan exceeds six metres. 6.2.8.10 Tapered walls shall be measured net as walls and extra payment shall be allowed.for making tapered surface for brick work in walls. Note: In calculating area of an opening, any separate lintel or sills shall be included with the size of the opening but end portions of lintel shall be excluded. Extra width of rebated re- measured and paid for separately. veals, if any, shall also be excluded. 6.2.9 6.2.8.11 6.2.8A Walls half brick thick and less shall 6.2.8.5 Walls beyondhalfbrick thickness shall be measured in multiples of half brick which shall be deemed to be inclusive of mortar joints. For the sizes of bricks specified in 6.1.1, half brick thickness shall mean l00mm for modular and 115mm for non-modular bricks. Where fractions of half brick occur due to architectural or other reasons, measurement shall be as follows: upto 114th brick -actual measurements and b) exceeding 1/4 brick-full half bricks. Rate: The rate shall include the cost of materials and labour required for all the operations described aoove except the vertical reinforcement and its encasement in cement mortar or cement concrete. The rate shall also include the following:- each be measured separately in square metres stating thickness. a) Brick work with brick tiles shall be 6.2.8.6 String courses, projecting pilasters, aprons, sills and other projections shall be fully described and measured separately in running metres stating dimensions of each projection. 6.2.8.7 Square or rectangular pillars shall be measured separately in cubic metres in multiple of half brick. a) Raking out joints or finishing joints flush as the work proceeds; b) Preparing tops of existing walls and the like for raising further new brick work. c) Rough cutting -and waste for forming gables, splays at eaves and the like. d) Leaving holes for pipes upto 150mm dia and encasing hold fasts etc. e) Rough cutting and waste for brick work ~urved in plan and for backing to stone or other types of facing. t) Embedding in ends of beams, joists, slabs, lintels, sills, trusses etc. g), Bedding wall plates, lintels, sills, roof tiles, corrugated sheets, etc. in or on walls if not covered in respective items and h) Leaving chases of section not exceeding 50cm in girth or 350 sq em in crosssection. 6.2.8.8 Circularpillars shall be measured separately in cubic metre's as per actual-dimensions. 6.2.8.9 Brick work curved on plan shall be measured like the brickwork in straight walls 149 i) 6.3 Brick on edge courses, cut brick comers, splays reveals, cavity walls, brick works cUIved on plan to a mean radius exceeding six metres. voussoirs shall break joints to the full depth ()f the arch. 6.3.2 Flat Arches: These shall be gauged arches of brick cut or moulded to proper shape. The extrados sha~l be kept horizontal and the intrados shall be given slight camberofl in 100 of the span. The centre of the arch from which, joints shall radiate, shall be determined by the point of the inter-section of the two lines drawn from the ends of the arch at the springing level and at 600 to horizontal. Brick Work in Arches (Fig:S) 6.3.0 The detailed specifications for brick work mentioned in 6.2 shall apply, in so far as these are applicable. Arch work shall include masonry for both' gauged as well. as plain arches. In gauged arches. cut or moulded bricks shall be used. In plain arches, uncut bricks shall be used. In flat arhes, bricks shall be laid with radial joints to the full depth of arch and voussoirs Brick forming skew-backs shall be dressed Oi cut so as to give proper radial bearing to the end voussoirs. Defects in dressing of bricks shal1 not be covered by extravagant use of mortar. nor shall the use of chips or bats etc. be pemlitted. breaking joints with each other. The arch w~rk shall be carried up from both ends simultaneously and keyed in the centre. The thickness ofthe joints shall not exceed 5mm. Flat arches may be used for the sake of appearance' but for purpose of carrying loads of the wall above, these shall be used in conjuction with relieving arches, lintels placed below. The bricks of the spandrel wall at their junctions with the extrados of the arch shall be cut I to fit the curvature of the arch. 6.3.1 Circular 6.,3.3 Centring and Shuttering: The centring ai1d shuttering for the arch shall be got approved by the Engineer-in-charge before the arch work is started ..It shaB be strong enough to bear the dead load of the arch and the live loads that are likey to come upon it during construction, without any appreciable deflec·· tions. Arches: 111ese shall be ei- ther (a) plain arches, and shall be built in half brick concentric rings with break. joints, or (b) gauged arches built with bncks cut or mo~ded to proper shape. The arch work shall be camed up from both ends simultaneously and keyed inthe centre. The bricks shall be flush with The shuttering shall be tightened with hard wood wedges or sand boxes, so that the same could be eased without jerks being transmitted to the arch. The sequence of easing ti'1eshuttering shall be got approved from the Engineer-incharge. The shuttering shall be struck within 48 hours of the completion of the arch but not before 24 hours. This shall be done after the mortar and well pressed into their positions so as to squeeze out a part of their mortar and leave the joints thin and compact. All joints shall be full of mortar and thickness of joints shall not be less than 5mm nor more then I5mm. After the arch is completed, the haunches shall be loaded by filling up the spandrels upto the crown level of the arch. Care shall be taken to spandrel has been fIlled in and the arch loaded. load the haunches on two sides of the spandrels. 6.3.4 Measurements: The length of the arch shall be measured as the mean of the extrados and intrados of the arch correct to a em. The thickness of the arch shall be measured in When the arch face is to be pointed (and not plastered), the face bricks shall be cut to proper shape or moulded, so as to have ,the joints not more than 5mm thick. These shall be laid ~th radial joints to the full depth of the arch. The multiples of the half brick. The breadth in the direction of the thickness of wall shall.be measured as specified. 150 The cubical contents shall b~ (~alculated in cubic metre,correc! to two plac.esof decimal. aoove except reLt1forGement which is to be paid fori)!, rep?xately, For arches exceeding 6m in spans extra yayment shall be made on the actual area of the 6,;5 soffit for additional cost of centring inCluding all strutting, bolting, wedging, easing, striking 'and its removal. 6.5.@ The work. shail be done .•in the same manner as described in 6.2.4 except that brick tile shall be used instead of bricks. The I!leasurement and rate shall be same· as specified under 6.2. ' 6.3.5 Rate : The rate is inclusive of the cost , Brick iHe work of the materials and labour required for all the ~ operations described above. 6.4' The brick honeycomb work shaH be done Vlrith specified. c1ass of brick, laid in specified mOftar. AJljoints ,md edges shall be struck t1ush (0 give. g!n even surface, Half Brick Work. ' Brick work in half brick walls sh~ll 00 done i..11 the same maimer as described aoove in 6.2.4 , except that the bricks shall be laid in stretcher bond. When the half brick work is, to be reinforced. 2 Nos M.S~ bars of 6mm dia., shall be embedded in every third course as given in the item (the dia of bars shall riot exceed 8mm), These shall, be securely anchored at their end where the partitions end. The free ends of t.qe reinforcement shall be keyed ioto the mortar of ' the main brick work to which the half brick The thickness of the brick honeycomb work shall be half ~brickonly, unless otherwise specified. Operrl.~gs shan be equal and alternate with half brick laid with a bearing of 2ero on either side. ' 6,,6.1 The length and height shall be measured cor'reet to a em. AreashaJl be calculated in squa.~ .metres 'correct to two places of decimal. Honeycomb .openings shall not be deducted work is joined. The m0ltar used for reiPJ'orced brick work shall be rich dense cement mortar of mix 1:4. Lime mortar shall not be used. Over laps in reinforcement;if than 3Ocm. ~y shall not be less 6.6.2 above. 5mm. The mortar covering in'the dirction of joints shall not be less than I5mm. '. Measurements 6.1.1 In case the height oftlie bricks of old as well as new work is same, the old work shall be . toothed to the full width of the new wall and to calculat~d in sq.m. where half brick wall is joined to the main walls of one brick or greater thickness the measurements for half brick wall shall be taken for its clear length from the face of the thicker wall. , the depth of a quarter of brick in- alternate courses. Incase the height of the bricks is unequal, then the heig~t of each. course of new work shall be made equal to the height of the old work by adjusting thickness of horizontal mortar joint~_inthe new wall. Where necessary, adjustment shall be made equal to thickness of oldwall by adjusting the thickness of vertical joints. Rate The rate includes the cost of the materials and labour involved in all the openitions described 11-4/CPWD/ND/92 ' 6.7 Joining Old Brick Work With New Brick Work The length and height of the \Vdll shall be measured correct to a em. T,he area shall be 6.4.2 R~te' 1be rate includes the cost of materials and labour involved in all the operations described The mortar interposed between the reinforcement bars and the brick shall not be less than 6.4.1 Measurements 151 6.7.2 For joiningne.w cross wall to old main walls, a number of rectangular recesses of width equal to the thickness of cross wall, three courses in height and half a brick in depth shall be cut in the main walls. A space of the three courses shall be left between two consecutive recesses. The new cross wall shall be bonded 6A3 into the recesses to avoid any settlement. 6.8.4 6.7.3 Joining of old brick work with the new brick work shall be done in such a way that there shall not be any hump or projection at the joint. For the pappose of measurements, the secDonal periphery of JI10wdiogs' and cornices (excluding the portion in contact with wall) shall be measured ill centimetres and length in metres (fig, below). The girth and length shall be mea..<rnredcorrect to a em. No deduction The mouldings and cornices shall be cun~dfor at least seven days. These shall he protected from the effects of sun. and rain by suitable covering and also from damage during t.1-Ie execution of the worle. 6.7.4 Measurement The height fu'1d tl'1ickness of vertical face in contact with new work shall be measured tathe nearestO.Olm and the 6$.5 Rate TIle rate includes the cost of Rate. The rate. indude3 the cost of materials and labour and material involved in all the operations described above. 6.8 Measurem.£nts shall be made from the masomy of wall for the bearing of the moulding andcomices. area shall be calculated to the nearest 0.01 sqrn. 6.7.S Curing ~nd pratection labour involved in all the operations described above. Moulding and Cornices 6.8.0 The specifications described under6.2 shall apply in so far these are applicable. Mouldings a.11dcornices shall be made with bricks as specified for brick work. The bricks shall be cut and dressed to the required shape as shown in the architectural drawings. 6.8.1 Cornices shall not ordinarily project by more than 15cm to 20cm and this projection shall be obtained by projecting each brick course by not more than one fourth of the brick course by not more than one fourth of the brick length. For cornices projecting more than 20cm and requiring more than quarter bricks projection, metal cramps shall be used and paid for separately. Note:1. The sectional Periphery Curve ABCDEF 2. Length FA shall not be measured 6.9 Brick work under water or foul posi~tions Brick Work under following conditions 6.8.2 Corbelling shall be brought roughly to shape by plastering with the specified mortar. When the mortar is still green, the mouldings shall be finished straight and true with the help of metal templates. i) Work in or under water/or liquid mud ii) Work in or under foul positions Shall be measured separately for payment of extra rate over and above the quantity measured and paid under. para 6.2.8 152 when tested in accordance with the procedure laid down and tolerance in dimensions shall be checked as pr:;r the pror..edure laid down in Appendix A-2. The facing bricks made from swtable soils shaJ1be free from cracks, flaws. nodules offree lime warpage and organic matter, These shall ht: thoroughly burnt md shill ha,\il':, plane rectangular faces with parallel side§ and sharp ::Jlrnightright angled edges. Fa(''h'1g bricks shall have unifonn colour and even texture. Unless oth~rwise specified, facing bKicks shall be machine moulded. Selected hand moulded bricks may also be used as facing bricks where sped;;ified.As far as possible, total reqmrement of facing bricks for a work shall be arranged froin the same kiln. Bricks with chipped edges and broken comers shall not be used. 6J,O.2 Dimensions Mortar, Soaking of Bricks and laying shall be as specified in. Para 6.2.2,6.2.3 and 6.2.4 respectively 6.10.5 Joints in the exposed brick work shall be truly horizontal and vertical and kept uniform with tbe help of wooden qr steel strips. The thickness o[ joints shall be as per 6.2.5.0. 6010.6 Curi.."1g l:U"1d scaffoJding sha.U be as specified in 62.6 and 6.2,7 to 6.2.7.2 ,respectively. 6.10.7' Measurements: and Toleratrftces: Exposed brick work in face using machine moulded bricks and selected hand moulded The standard sizes of machine moulded fa.cing bricks shall be 18 specified in6.1.1 bricks shall be measured separately and the measurement shill be as specified in 6.2.8. 6.102.1 The permissible tolernncese shall be as under:- mm ±3 ± 90 40 III 190 or ± 1.5 or 44 225 Toleran;~e(For 6.10.8 Rate~ ,--~~ --- The rates shall 00 as specified in 6.2.9 and shall also include the following :- Machine ded bricks)moul- Note: Tolerance & Dimensions for selected hand moulded bricks ±4mm in length and ±3mm in width & thickness) 6.10.3 Sampling- As per Para 6.1.3 6.1.3.2 a) Labour for selecting bricks and wastage of bricks where use of selected hand moulded brick is speccified. b) Leaving unifonn horizontal and vertical grooves of specified depth and providing joints of required thiclr..nessusing wooden or steel strips as the worle proceeds. 6.11 Cavity Wall: It is a wall comprising of -two leaves, each leaf being built of masonry units and separated by a cavitY so as to provide ·an air space within the wall and tied together with metal ties or bdnding units to ensure that two leaves act as one structural unit. The width of the cavity shall not be less than 50 mm. and not more than 115 m.m. Each leaf of the cavity _ wall shall not be less than 75mm. The space; between the leaves being either left as cavity or fill~d with non-load bearing insulating and water proofing material. & 6.10.4 Physical requirements: Facing bricks shall be of class designation 75 unless otherwise specified. Average compressive strength shall not be less than 7 .5~/mm2 water absorption shall not exceed 20 percent by weight and efflorescence rating shall be nil 153 6.11.1 M~talTieg:Tnese maybeofgalvanisd iron, wrought iron, gun metal, brass, copper, stainless steel or any such corrosion resistant metal, made of flats 20 X Sm.m. cra.'lked or twisted at their. mid point with ends split and fish tailed; The ties shall be built into hOIizontal bed joints during erection, placed sloping towards \he exterior side to prevent water from flowing along it from outer to inner leaf sid~ (For details refer. fig. 6 on page, 164-1 (-is) a) b) bonding unit sp-.;cifying the numbers pe:r square metre. c) Length of the Bonding units will he sum of thickness ofoom leaves plus width of cavity if me leaves are 75mrnor 115 mm. If the leaves Labour matedal for dosing cavities at the jarnbs, sills and heads of opening a..."1c! shall bl'; as described and measured scperatcly in running metres. are more than 115mm thick, then the length of a UJ'Ijt will be 2X] 15+ width of cavity as shown in Fig. 6 on page 166. Precast RCC units shall be provided with 2 no.; 6mm mild steel reinforcement bars tied with 2 no. 3mm. dia.m.s hard drawn wire cross bars (As shown in Fig.6h on page 166) placed in the centre of units. d) Cement concrete used in the bonding units shall not be leaner than 1:3:6 (lcement:3 coarse sand:6 graded stone aggregate 20mm nominal size). 6.11.3. Spacing: Metal tieS/bOndingunits shall be spaced not more than90 em apart horizontally and 45 em vertically and staggered in each oour~. Additional ties shall be used near openings. Restrictions: :fhe forming o[the cavi~ shall be given in square metres stating the width oftI'1e caviry and sha11 include the metal ties! 6.11.2 Bonding Units: These shall be preferably precast RC.C. units having cross-section as per fig. No.6. 6.11.4 Brick work ht cavl!ywalls sh211 be inGlll<.kd ~nd measured Vll[h gencr:il brick work ..The width ofrhe cavity shall not be measured. Skin of cavity wall, half brick thickness shan DCmeasured as & p:;id as described in 6.2.8 & 6.4 Cavity walls shaH not normally be built Cmore 'thaIl 7.5 metres in' height and 9 metres in length;. Where large lengths and heights afe: desired, the wall shall be divided into p:me:ls with strengthening measun~s such as piHars etc, Cavity shall be covered at lhe top with at least two courses of masonry unit and/or a coping over it. Adoption of cavity walls is nm: recommended when heavy concentrated ImKlfrom be:ametc. ;lfC to be supported by walis. 154 The lW1Y1 shall i.rlclude use of device for keeping cavity clear a.nd fonning the requisite weep and vent holes and nothing extra on this account shall be payable. APPENDIX A TEST H)R DIMENSfONALTOLERANCE (Para 6.1.33) Non-Modular Bricks A - '(~%mpUng ; As per para 6,1.3.1 &,6,1.3.2 .4.. - POI' 2ProGcdme : iJI th~ bJistem, loose part~,clcs(Jf clay and small fjIvjccti0ns shall be removl:d from the surface of bricks. Each ~;p{Cdmcf1of 20 bricks sha.ll then be arr:.mgcd upon a level surface successively as indicatcdln fig. A-3'and C in contact ,"vith each other and in straight Une. The :)veraH h:ngth ("fthe assembled bricks (20 Nos) shaH t~ me3Bured witl1 a steel tape sufficiently long to measure t,e \vhole row at one stretch. Length 441 to 459cm 'Width 218 to 226cm Height 138 to 142cm (FOi 70mm high bricks) 86 to 90 em (ForM mm high bricks) For other classes A - 3 Tolerance : The actual dimensions of bricks when tested as descIibed in /\-2 shall be within the foUmving limite; per 20 bricks. Modular "Bricks 7610 84cm (80 ± 4cm) for 40mm high brick '13' MEASUREMENT Length 432 to 468cm Width 213 to 231cm Height 134 to 146cm (For 70mm bricks) high 84 to 92 em high (For 44mm bricks; A - 4Crireda for conformity. A lot shall be considt;red. conforming to the require1Xwnts of dimensions and tolcrance.<; if aU (he groups of bricks are tested to meet the specified requirement.;; .. Height 176 to 184cm {tHO ± 4{~m)for 90mm high brick A1\tfEJ\SUREW1ENT class 10 OF LENGTH OF WIDTH 'C' lYfEASUREMENT OF HEIGHT 155 APPENDIX 'fEST FOR COMPRESSIVE B STRENGTH (Para 6.1.3.4) B-1 Specimen Five whole bricks shall be taken from the sarnples as speclllens forthis test Length and width of each specimen shall be Load shall be applied carefully a.>dally at umfonn rate of 14 N/mm2 per minute till the failure of the specimen occurs. :8-4 Reporting the Test Results: 'measured correct to Imm. B-2 Apparatus The compressive strength of each sped· men shall be calculated ii1 N/mm2 as under: The apparatus consists of compression testing machine, t'1e compression plate of which shall have a ball seating in the form of portion of a sphere the centl"f~of which shall coincide with t.qecentre oftl'1e plate. B- 3 Procedure (a) Pre-conditioning The specimen shall be h'TimelSed in the water for 24 hours at 25:>to 29°C. Any surplus moisture shall be allowed to dram at room. temperature. The frog of the, bricks should be filled flush with mnrtar 1 : 3 0. cement: 3deancC\!iirse G&'1<1ofgrade 3mm and down) and~haTI be kept under damp jute bags for 24 hours afterthat these shall be immersed in clean water for three days. Afterremoval from water, the bricks shall be wiped out of any traces of moisture. (b) Actual testing SpedInen shall be placed with fiat horizontal and rnor!:<'ty fm~~d face3 face upward hetween tllIee 3- ply plywood sheets each of thickness 3i1:ifil and carefully centred between plates or the testing machine. PIal;;'· tef ot'Paas can also be used in plac.e of plywood sheets to ensure a \1pjfann surface. , \ Compressive Strength == --------'-.- Maximmn load at failure (in N) Area. of Specimen (in sq mm) In. case the compresive streng'"J1 of &"iY individual brick tested exceeds the upper limit of the average compressive strength specified for tIlt:: corresponding class of brick,the Saine shall be limited to ti'1~ upper lLmit of the class specified in 6.1,1 for the purpose of calculating the average compressive- strength. Compressive strength of all the h"1dividual bricks com·· prisi.'1g the sample shall be averaged and reported. 13-5 Criteria for confonnity A lot shall be considered having satisfii~d the requirements of average compressive strength if the average comprestdve stiengtl1 specified in 6.L2forthe C01re· sponding class of brick tested is net bellOW the minimum average compressive strength specified for the corresponmr!.g class of bricks by more than 20 per~nt APPENDIX C TEST FOR 'INA,TER ABSORPTION (Para 6.1.3.5) C-l NO OF SPECll\IffiN and then shall be weiglled wittJn thrtc minutes after removing fm111 \'/~ter0N2) , Five whole bricks shall be taken from samples as specimen for this test., C-4 Reporting L'1e test results C-2 Apparatus A ba1<,',ncerequired for this test shall be The water absorption of each specimen shall be calculated as follows and t.l-te sensitive tu weigh ~ll percent of the average of five tests shaH be reported. weight of the specimen. W2 - WI C-3 Procedure (a) Water Absorption:::: --WI 100_ Pre-conditioning C-5 Criteria for conformity The specimen shall be allowed to dry in a ventilated oven at a 11[jJ C to 115° C till it attains a substan- A lot shall be considered having satisfied the requirements of water absorption if tially constant weight. Uthe specimen is known to be relatively dry, tlrls would be accomplished in 48 hours, if the specimen is wet, several additional hours may be fi~quired to attain a constant weight. It the average water absorption is not mq:re than 20% by weight. shall be allowed to cool at room temperature. In a ventilated roorn, properly separated bricks will require four hours for cooling, unless electric fan passes air over them , continuously in which case two hours may suffice. The IXJOled specimen shall be weigh ('iN!) a warm specimen shall not be used for this purpose. (b) X Actual TesTh"1g Specimen shall be: (X)rop1etely dried before immersion in 'the water. It shill bf;;kept in clean water at a temperature of 27° c ± 2° c for 24.hours. Specimen shall be -wiped out of the traces of water with a, damp doth after removL'1g from the water 157 APPENDIX D -- TEST Iti'OR EFFLORESCENCE (Para 6.1.3.6) d) D-l No of specimen Five whole bricks shall be taken as Sf..-ecimen for this test. unaccompanied by powdering flaking of the surface. D-2 Apparatus . (e) Apparatus requued for this test shall be a _shallow flat bottom dish. containing distilled water. D-3Procedure (actual tesuIlg) A lot be considered having satisifted tlv~ requirements of- efflorescence if for 4 out of the specimen of 5 bricks, the effloresence is not beyond ralingof "Moderate", shall be examh"1ed aft<;rIDe second evapo- ration. D-4 Reporting the test results The rating to efflorescence in ascending ordershallbereporteda.s 'NIL'. 'SLIGHT, 'MODERATE, 'HEAVYo:\,'SER1:0US' in accordance wi~h the following. SLKH~iT: When not moretban 10 2.xe:a of lh~~bri<:K is 'c:'()vered wid~ a:t~~J11. dCP{l~it:of :~'i~lt~. C)MODERATE: -SERtOUS: When there is heavy D-5 Criteria for conformity The room shall be warm (18° C to 30°C) and well ventilated. ri11e bri~ks showd not 00 renlOved until it absorbs: whole water. When the whole wateds i.1hsoru:;;d lli"lG tlt'J.,f.:: brick appea.r-s to t~ dry, place: a similar quantily of Vfat:~rin that dish and «_11 • m evaporate -" ,.,,,,, - • " 1d.IO'N It 2iS ,~, l!'trc01-e" i ne tlm:x percent f;f t.he or deposit of salts, accompanied powdering and/or flaking of the surface and tending to increase in the repeated wetting of the specimen. '(he brick shcill be placed vertically in the dish with Z;5cm irnmersed in the water. B) REA VY: When theH~ is a heavy deposit of salts covering 50% or more of the brick surface but When there is he<.wier deposit and CO\N;:r".ng upto 50% ofL.1.e area Gfihe brick surface but una·ecompanied by :~x'fwdcring or flaking of u'1e surface. 158 B.R'·C K WO R K CHAPTER - BRICK ",'ORK CLAUSE - 6,0 P. 6 '2·~ FIG. 1. . OV ERSAIUNG• , COURSE--Lj""',- 'UD > _ .SlA CO P! NG PHUSI(~ ~T'lEr ~I 1 s---.F: ': .... -.,.':.~.... : " :.~ ···~··i 1 . - ~.----rORNW!=" '"I't"'o I ..' .~- ., -Sn~ING COURSE A. PI E R ( 1) WI NOOW SILL B. PIER (2) ope C. PILL AR S THE BREAOTH SHALL NOT D. TYPICAl. E: XC!.:: EO 5£ C TION, THREE TiMES THE THICKNESS }.,NO THICK NE 55 ITSE LF SHALL NOT EXCEED ORA WIN G NOT MORE TO THAN THREE SCALE, 159 BRICKS OF SRI C K W.b.LL / PILLARS BRICK on D EVEN ~OUR 5ES CHAPTER - BRICKWORK CLAUSE FIGURE - (OUR SES 150 [I] Etfl .{100 ~. 1 X 1V2 BRICK -t 200 ..... !.. 0-¥ .. 4"I EEf or 1 X 2 BRICK Rl ~t [DIU . 1V2 ~ X 2 8RICK~ '2 X 2 DRI CK S··n" "~') Er~GtJSi1 .."\}N~,,,"; I Drawing All di A 0 t to men$ions 5ca.t@. or e in rnm. 160 !;,2.4J - 2. BONDS 8 RI C K ODD COURSES B bt 10~_ sot EVEN H - ---'------BR! CK WAll n t g\ Nt --~-WALL WALL ,,--_._- :2 8 f<jCi( .--,",,-..-..... BOND II at' to seal e dim2!1siohs are in rnm. Dru wing All FIGURE COURSES '] Closer . -• II 1 Queen CHAPT ER C LA U 5£ 161 - BRICK WORK. £). 2 . £1. 1 3. ODD CHAPTER - am::x CLAUSE - 6.'2.[,.1 FIGURE - 4. COURSES ./ CUT ""7 •••_ Dr ;\([ Ci win 9 .. BR!e:.:: CORNER (MAFH)CONAt./~ no \ 'to scale. or Q. .in mm dimensi on~; ·._. __ -_-~· ----- 162 WORK CHAPT ER - BRiCI< WORK CLAUSE-S') FIGURE 5. r extrados back iau~__ ~__ .joints no! I1 mar-=: than 51T1fT1 - or - soffit th ick I. joints from th irk or 5'p~irging jtntrados POI~!~ I -. --r----;:. ED PLAIN CiRCULAR OR ROUGH ARCH span - qNE . FLAT _ GAUGED - ARCH 163 j)rnwi ng n at to sc ali2 . varying to 15 mm abutm ent span GAUG 5 BRICK THICK m CHAPTER - CLAUSE FIGURE - 6'11· - 6. co ping - - ~ :r'oof BRICK WORK Q level M~NM met 1: 50 Cavity :i> tie or 01 bonding 115 -- uni t cavity to start 75mm (c.d SECTIO~ OF _ norma'lIy I 230 mm wall O(J tie bonding g.t. WALL CAVITY 115 but not Ie 5S than -75mm in any case met a -above l. G. from unit ( b 5 E.CT I aNA l j Pl AN - M M c av ity or 115 If.!ss ----1-. PLAN (c) 115 AT or I p.ss MM or 115 .side less mm faceout---i§3:§=-75mm ~ (d) PLAN 75mm -----EJ (.) PLAN AT MM ·[3--75 AT NOTE:- mm 1) Only one of the alternative a. b • c ,q or e sh a II be app I icable in ea ch case 2JTies shalt be placed sloping towards exterior si de. MM 164 FIGURE - 6. CONTIN UED W~II ti e po.Sition rUnbonded Jamb ~ ~ o a M ~I --! ~ ~t ~I -+-- ~I -k:- "1 I -t- ~ + ~ k- AS 900 MM NEAR TO -+ 900 MM ¥_ AS IS PRACTICABLE OPENING (f ) .E LEV A T ION METAL METAL (9) ISOMETRIC 165 VIEW TIE AS TIE AS, PER PER DETAIL DETAIL FIGURE - 6 . CONTINUED MET AL ( i) 3mm =- _ 1 height L >~1 ---"-'----L 1- course thidness :to- (h ) 2 X 11 5 . L = sutn of two lef1ves .• cavity 2 X 115-. CQvit y (for walls 11 5 rn tn or tn 0 r e ) tof walls-"'cavity .•. c a v t Y (For wo.u.s 115 10m(;)1' 1110re ) i 80 N01N G UNIt. 8 LY ~~ ---C2-36 DETAILS ~mOE J (PREFERA (J) TIE m.s. hard drawn wire OF P RECAS T .R.C.C.) m.s. 'bars mm m.s. wi ref hard mm REINFORCEMENT IN drown wire BONDING 166 UNIT I NOTES I :l-4/CPWD/ND/92 167 NOTES • 168