Rebar mesh: Cut and lay 6-inch rebar mesh across the site, covering all areas except for a 3-inch band on the outside. Pouring of floor 2's slabThe dead loads include the self-weight of the slab, floor finishes, walls, grills, etc. (150 to 250 mm). slab along the shorter span, 3mm per meter span. The commentary R26. ACI 318-14. 15m and then Sand level is rammed. For flat slabs like driveways and patios, spacing is roughly 18″ to 24″. 3. If your two slabs have different spacing for their rebar mats, measure and mark so your dowels fall in the middle of the spacing of the second slab. Design Rules - Footing/Pile Cap Rebar. Suresh, Professor, Civil Engineering Department, NIE, Mysore (Ph:9342188467, email: gss_nie@ yahoo. Clear cover of the slab = 25-mm. 5 Footing and slab construction. g. Two-Way Concrete Floor Slab with Beams Design and Detailing Design the slab system shown in Figure 1 for an intermediate floor where the story height = 12 ft, column cross-sectional dimensions = 18 in. 5 bars; There shall be a minimum clearance between parallel reinforcement bars of 2 1/2 inches; Bars larger then # 5 increase the chances of shadowing (voids behind rebar) Always use the larger of the two. The Construction and Design of Concrete Slabs on Grade D. and the clear spacing between the bottom bars a = 60 mm. The result is a lightly reinforced slab designed to offset the effects of temperature and shrinkage of the concrete. Minimum spacing between reinforcement bars in foundation tie-beams Concrete casting in foundation tie-beams is not an easy procedure. Section 13. 4, and No. MTOTAL SLAB Rebar SPACING, LOCATION Shear THICKNESS Size (Ø) mm REMARKS kN-m. Here, ∅ is the bar diameter. 9 m in buildings with light wood-frame walls, floors and roofs, footing widths shall be determined according to. 2. These new concrete slabs do not account. Locating conduits (plastic & metallic) and in-floor heating lines in concrete, or just below a slab-on-grade. 00 m 7. Slab Design Rules - General. 6) Calculation of top rebar Please refer to the method in construction site as follows because it is very difficult to explain in theory. Sixteen gauge wire is used to tie. x 27 in. These beams are not fixed together with a slab as are superstructure beams; consequently concrete has to be poured down the beam’s narrow top opening and reach the bottom of the beam. For multi sided slab, first draw the shape: 1: Hit Clear + Start and enter Side Length of first side to draw, then hit appropriate direction (Arrow) button to draw. 15 mm) polyethylene vapor retarder with joints lapped not less than 6 inches (152 mm) shall be placed between the base course or subgrade and the concrete. The cross‐sectional area of one N28 bar is As = 620 mm2 and with N12 stirrups at 150 mm centres, Atr = 110 mm2. each way at center of slab construction joint for same shall not be more than 3000mm apart. A slab with this joint spacing may be reinforced with bars (ASTM A 615, A 616, A 617, or A 706) or WWF (ASTM A 185 or A 497). The #3 rebar has a weight per length of 0. Here, ∅ is the bar diameter. 8 mm) when subjected to 50 pounds (23 kg) applied over 1 inch square (645 mm) of material and are greater than 1/ 8 inch (3 mm) in thickness in the uncompressed state shall not extend beneath walls, partitions or columns, which are fastened to the floor. The Rebar and Concrete in a Slab calculator computes the total length and weight of rebar and the volume of concrete needed for a slab. Minimum aging of new concrete slab: 28 days (cure time) Minimum width and length of slab: See new slab table & figures below MIN W L R S1 & S2 D I LIFT MODELS SLAB MIN. • A beam-and-slab system, with a one-way slab, and beams cast compositely with the slab, is a highly efficient floor system. The maximum spacing of temperature steel is the smaller of 5 times the slab thickness or 18 in. The elevation to the top of the decking (bottom of the concrete waffle slab) for forming of the second floor above-grade slab is ___. The two design options are a ground-bearing slab, or a pile supported suspended slab. 75 to 3. Reduce evaporation over the slab by using a fog spray or slab cover. This calculator finds rebar sizes and spacing for beams, girders, and 1-way slabs for a particular type of reinforced concrete floor system consisting of a regular grid of columns supporting a hierarchical. The spacing of the rebar is also determined by the weight and size of the slab. The spacing of the rebar should increase to between 18 and 24 inches apart for slabs between four and six inches thick. In some cases, concrete needs reinforcement with steel mesh. The thickness of concrete floor slabs supported directly on the ground shall not be less than 3 1 / 2 inches (89 mm). Technical Details of Steel Decking in Composite Floor Slabs. 64 mm) between longitudinal rebar 2 and 3, which is the same as the rebar construction and traditional tape measurement results. 5/16" 2" long bolts thru tight holes spaced 3" apart at the outer ends and then increasespacing by 1/2. 42d. 21 m 2. 1 the spacing of links along the FULL HEIGHT shall not exceed 6 times diameter of smallest longitudinal bar or 150mm. INSTRUCTIONS: Choose units and enter the following: ( L) Length of the slab. Selecting the correct type of rebar is as impor tant as the diamet er and grade. The support for reinforcing steel in floor slabs is shown in figure 7-24. Heavy Loads. 1 Flexural Cracking in Reinforced-Concrete SlabsFor mid-depth rebar, the program will use the bottom bar size and spacing options. for slab depths up to 9 in. To reinforce a 4” concrete slab or driveway with steel rebar, determine the grid spacing and rebar size – #3 or #4 in a 12” to 18” grid. That has held up great over the last 8 years, no cracks at all. For example, The #3 bar size is 3/8″ diameter of the solid section, the #4 bar size is 4/8″ diameter of the solid section, and the #5 bar size is 5/8″ diameter of the solid section. x 18 in. e. The maximum diameter of bar used in slab should not exceed 1/8 of the total thickness of slab. The diameter of bar generally used in slabs are: 6 mm, 8 mm, 10 mm, 12mm and 16mm. If you are using rebar under the weight room, raise it on stools, tie it off in a 12" grid. Pour 6" fiber reinforced concrete over it. A 6-mil. The basic building block of this application is further known as a composite floor slab. Table 7-6. The term "composite steel deck floor slab" is applied to systems in which the steel deck has some mechanical means of providing positive interlocking between the deck and the concrete. To define design strip rules, click the Slab Design Rules button on the Data Entry toolbar. 2 mm) in thickness in the uncompressed state shall not extend beneath walls, partitions or columns, which are fastened to the floor. In general,. Tying is required at every second or third intersection, depending upon the size and spacing of bars, but with not less than three ties to any one bar, and, in any case, not more. standard rebar lenght is normally 12m or 6m each. Measure the cover depth of embedments. It may be desirable to tie and reinforce the new slab to the pre‐existing surrounding floor. e. 4 welded wire reinforcement fabric located in the middle to the upper one-third of the slab. For columns and beams, the minimum spacing should be 6 inches. Build the wall full height, place concrete continuously in 4-foot lifts, and consolidate each lift. For a 400 square foot slab, the man hours required to finish a two-car concrete garage slab is about 13 hours. on center, but this will depend on the structural design. Because of this, the Building Code places limitations on the size and spacing of rebar in gunite & shotcrete. The second marker expresses the bar size and is demonstrated by a number. With our rebar calculator, you can eliminate. 6 of the International Building Code. 6: 20mm clear cover in slab is sufficient. long-term deflections of the slabs. Then use USDA NRCS Standard Drawing ES-46 to select ( ) There's no generally-accepted rule of thumb as to how to space rebar in a concrete slab. of main bars – One = [Lx ÷ bar. The Rebar Calculator contains equations and data used in working with reinforcement bars (rebar) in concrete slabs. Since this is a patio, you could use 6x6 10/10 wire mesh instead of the rebar. Concrete slabs: Contractors often use the 1/8 rule for determining the size of steel for a slab. For these cases, the flat plate is economical for spans between 15 ft and 20 ft. The maximum size of reinforcement shall be No. Finally, take a look at the calculation results: grid length = 5. Because of this, the Building Code places limitations on the size and spacing of rebar in gunite & shotcrete. Learn the steps to pour a concrete floor inside an existing garage, house or shed. 2. 3. 15% of the slab’s cross-sectional area), the spacing of tendons in at least one direction shall not exceed the smaller of eight times the slab thickness and 1. This configuration directs load transfer predominantly in a single direction toward the columns. The specified compressive strength of concrete shall be as set forth in Section R402. But if the slab is a patio or driveway, it will need rebar. Contraction joints (or control joints), when cracked, are really just straight shrinkage cracks. 83-6. worked on the rebar behavior inspection of a sustainable RC slab. Avoid using air contents over 3% for interior slabs. Larger areas, lower loads, and higher seismic zones. In order to calculate this, you need to input the length and width of your slab. Design the slab system shown in Figure 1 for an intermediate floor where the story height = 12 ft, column cross-sectional dimensions = 18 in. The top of the wall will need "hooks" in the rebar in order to fasten the wall to the garage slab. The fibers must be high quality and tested to verify consistent strength. 1 of EC2, the recommended minimum spacing of reinforcing bars is 75 mm and 100 mm for laps. Place these positioners at a spacing that will not allow the rebar to bend or deflect enough to reduce the coverage you wish to obtain with the concrete you place in you forms. 2 m top bars @ discontinuous edge Compute temperature bars 250 Using 10 mm f bars:. 10. These provisions are not meant to prohibit the use. Floor slabs can range from a simple residential basement slab to a heavy-duty industrial floor. 3%. I generally use a minimum of 4 bars, with 2 bars of 12 MM thickness in the bottom of the beam, and 2 bars of 10 MM at the top of the beam. If the concrete slab in question is meant to be the footing of a house, then #5 rebar with a. For slabs (i) The maximum spacing between two parallel main reinforcing bars shall be 3dor 300mm or whichever is less, and (ii) The maximum spacing between two. For multi sided slab, first draw the shape: 1: Hit Clear + Start and enter Side Length of first side to draw, then hit appropriate direction (Arrow) button to draw. 1) for con-c r ete cover over re i n f o rc e m e n t h a v e not been consistent. The floor has been designed with two mats of steel, 7 1/2" total concrete thickness and 50 ksi steel beams with a single row of shear studs on the beams. For driveways and patios, #4 (1/2 inch diameter) rebar is a common. Two-Way Concrete Floor Slab with Beams Design and Detailing Design the slab system shown in Figure 1 for an intermediate floor where the story height = 12 ft, column cross-sectional dimensions = 18 in. It requires input values for the dimensions of the slab, the size and spacing of rebars, and other parameters, providing an estimate of the required rebar quantities. 00 m 7. Whether the frame is precast, cast-in-place, masonry, or structural steel it can be accompanied by a HollowCore floor slab system. t 12mm stirrups at 150mm ctrs Two terminated bars A A Elevation Section A-A Lsy. The rating your floor can withstand is also factored in. girder sides & slab on grade - 1 reinforced concrete beams 6 mm for every 4. 00 m 21 reinforced concrete slab 3 mm for every 3. The maximum anchor bolt spacing shall be 4 feet (1219 mm) for buildings over two stories in height. The ACI 318-19 provides a number of requirements regarding slab thickness, concrete cover, and reinforcement ratio which facilitate the design process. SLAB—Flat section of floor or roof either on the ground or supported by beams or walls. Provide the required spacing and diameter of the rebar. The shear reinforcements are provided from the support. The spacing of the main steel in a slab should not exceed the following: First, the American Concrete Institute (ACI) Residential Code Requirements for Structural Concrete (ACI 332-14) requires contraction joints and provides a table to determine joint spacing for plain and reinforced concrete containing up to 0. ( D) Depth of slab. In the case of the RCC slab, the maximum spacing between the two parallel main reinforcement bars should be 3D or 300 mm or whatever. The tendency is to lay rebar the way one’s. Note: Unless otherwise specified, all code references for elevated slabs are to ACI 318-14/ACI 318-11. unless otherwise noted, all slabs on grade are to be reinforced with 10mm bars at 400mm o. The article elaborates the elastic and inelastic methods for design of. Minimum aging of new concrete slab: 28 days (cure time) Minimum thickness of concrete slab: See new slab table & figures below. Number of Main Bars = Ly / spacing + 1 = (4000/150) + 1 = 27 nos. If too much water was. This wood sheeting, which should also be stronger than average, will act as a subfloor. 84 m; grid. For live loads of about 50 psf (2. And a cross-sectional area of 0. An example is shown in Fig. Concrete doesn't dry out; it undergoes a chemical curing process that creates a dry, solid mass. Use wire mesh for driveways that are 4 to 5 inches thick, and rebar for those that are 5 inches or more. Kim Min-Koo et al. 53 m). These slabs are supported directly by the columns and have a completely flat soffit. #construction #Philippines #staircase #stair #stairs #stairsPhilippines#steelbar #rebar #stairrebarRebar details for stairs and slab ThicknessAmerican Concrete Institute—there's not much available free from ACI, but if you want the best information on concrete and concrete parking lots, ACI has it. ** For alternate steel schedules and/or slab thickness determine As (end area of steel, in2) as shown below and use USDA NRCS Standard Drawing ES-46 to select bar size = and spacing that meets or exceeds the computed end area of steel. 5 kPa), column spacing typically ranges from 15 to 25 ft (4. We would like to show you a description here but the site won’t allow us. This is one of the types of concrete slabs. LL = 6. 2—Slabs-on-ground 5. g. For slabs of septic tanks, you usually use #3 and #4 bars. Determine the rebar gauge. 🕑 Reading time: 1 minute The design of reinforced concrete (RC) column is carried out by following certain procedures. #3 is most commonly used for patios and driveways, #4 for columns and walls, and #5 for foundations and footers. Also, a small hole in the concrete will be totally fine, given the fact that there is a rebar grid. 4 rebar in the lower part of the foundation. longer than the length of the slab. ACI 330R-08, Guide for the Design and Construction of Concrete Parking Lots is. Learn More. make sure rebar is in the center of the slab, or close to it. Rebar size and spacing is dependent on the strength required. Use 2” rebar chairs to support the rebar in the center strata of the pad. Penetrations in PT slabs are possible when observing proper methods. 4 rebar in the upper part and one piece of No. Most homeowners can expect to pay between $4. Once the wood sheeting is down, add a covering of plastic. 15. Thank ForSubscribeLikesShare. Rebar Spacing. 5" 3,000 PSI / 28 Day Aging. For areas where heavy vehicles or equipment may be placed, our independent third-party engineers will specify rebar reinforcement for concrete slabs on grade. S. Design beams B1, B2, B3, B4, and B5. #4 rebar is commonly specified to reinforce the thickened edge. For corrosion protection, however, most specifications require a minimum depth of concrete cover that usually ranges from 1 inch to 2 inches. Wood blocks should never be used for this purpose. Note: Cut the two side form boards 3 in. Common Rebar Sizes. Ilang Araw Ang Pagbuhos Ng Simento? In this video, I'm sharing you the process of concrete pouring and sizes/spacing of rebars for the beams and slab concrete for the. (i) The maximum spacing between two parallel main reinforcing bars shall be 3dor 300mm or whichever is less, and. ( W) Width of the slab. Once you have determined that the foundation of the house is strong enough to sustain a concrete floor, lay down wood sheeting. (a) A flat plate which is a two-way slab supported on a column grid without the use of beams. 00 m to 6. The slab will be 3" thick with 2. The suspended reinforced concrete slab is tied into the external capping beam. It is possible to pour a concrete garage floor without installing rebar for reinforcement. 23 Total factored load = 6. Prices for your concrete slab will vary. Insert plate. First, Get The Number Of Required Bars. 2 cm) from the bottom of the concrete, and side clearances range from 2 to 4. Calculate how much rebar you need to reinforce a concrete slab. In this video i will show you about 2nd Floor Slab Rebar. for concrete floor construction are found in ACI 360R for slabs-on-ground, ACI 223R for shrinkage-compensating concrete floors, and ACI 421. Here: Bar Tying Requirements. REBAR SPACING: GP‐7 SERIES MODELS: 4‐1/​4" 3000 PSI / 28 Day Aging #6 Rebar:. Sunitha K Nayar, gives the grouping of slabs-on-grade based on the design philosophies and a brief overview of the different design methods, the commonalities between design strategies in terms of the input parameters, assumed and estimated parameters, and the relevance of each. What Size Rebar for Concrete Slab? This usually depends on the intended workload. Rebar Development Length Calculator is a web application that supports the design of post-installed rebar in concrete applications by calculating the necessary tension and compression development lengths required in accordance with ACI 318-19 / ACI 318-14. Normally, it is assumedchanges in deck slabs, and sloped slabs over beams. Rebar spacing in a slab footer will depend on the size of the slab, the load it will support, and local codes. Commonly called “rebar,” these 1/2-inch-diameter steel rods are embedded in the center of the slab to create a grid that extends lengthwise and crosswise to help the concrete better resist pulling and bending forces. Maximum spacing of bars for slabs • Main bars: 3h ≤ 400mm. S. Our calculator will instantly calculate the quantity of rebar required. x 20. 50 m span joist, beams, & girder soffit under 3. Added to that, the forms shall be properly cleaned and oiled but not in such amount as to run. Reading time: 4 minutes. ) slabs are plate elements used to form the floors of buildings. Generally, rebar spacing in slab footings ranges from 12 to 24 inches, both for horizontal and vertical bars. For footings that are poured before the slab, two #4 horizontal pieces of rebar are required – one 3” from the top and the other 3” from the bottom. 00 m span 3. Unit 571 New Smyrna Beach, FL 32128 386-882-EZCE(3923). . The main reinforcement of the slab panel “A” is marked as (1). 74 sq feet 5000/2. In this video, you will learn the Spacing between the Main and Distribution steel bar. Vibratory loads. 600-2 DETERMINATION OF BUILDING WIDTH A. Unfortunately, rebar can cause extensive damage to construction tools if you are performing coring or concrete cutting work. These large slabs are stre n. L. the slab joint spacing should be the same as for an un-reinforced slab. I was thinking of going with the same spacing. -Multishearing. Such applications usually involve the placement of large numbers of bars with close spacing. 006 inch; 0. Essentially a early age concrete shrinkage problem (cement paste not reaching full strength/bond with aggregate and restraint on the concrete member due to rebar. Select the unit of dimension like meter, feet inch, etc. 2 and 9. • Edge beams act as L-beams, and interior. Annex. x 20 in. Pour 6" fiber reinforced concrete over it. However, this is the absolute minimum and applies only when there is no load on the concrete slab at all. vided in the slab under the net. Stainless steel rebar. Spacing of mechanical shear transferring devices, s, where variable from one profile to another; and . Lower composite deck-slab weight than 3WxH-36 for the specified concrete thickness 8 inch on center low flute spacing to allow for bearing wall studs to be at 16 inches on center Non-composite deck 7⁄ 8 inch depth, 32 inch coverage 2 foot to 7 foot Span Range No Acustadek® Options Good for short span conditions1. The movements of these structural elements are likely different than those of a slab-on-grade due toWhen operated by our highly trained Project Managers, GPR’s typical accuracy is +/- ¼” to the center of the object in concrete we locate: conduit, post tension cables, and rebar. If your two slabs have different spacing for their rebar mats, measure and mark so your dowels fall in the middle of the spacing of the second slab. If Steel grade 60 is to be used, the minimum slab thickness is taken as L/20 where L is the span of slab. 1: Calculate The Main bars. In this video, you will learn the Spacing between the. Dosage amounts shall be from 0. 1 For longerfloor slab rebar' • ~ #4 19 mk402 "rll ~ ii i i i i i i i i i i i i i i i i i i i k '&y ih:' ii~. For Greece, the maximum aggregate grains dimension for usual concrete, is 32 mm and for self-compacting. 3% (100As/bd < 0. These new concrete slabs do not account for second floor installations or installations in a ground floor with a basement beneath. 2. )(100)/(6 in. less than around 0. last quarter of 2014, the prices i got for the rebars (12m lenght) are: 9mm deformed rebar - P110 10mm - P138 12mm - P205 16mm - P385. Understanding the Importance of 2nd Floor Slab Thickness for Building Safety and Stability in the Philippines The safety and stability of a building depend on various factors, and one of the most crucial is the thickness of the second-floor slab. . 2-way slab rebar arrangement method 1-way slab rebar arrangement method Slab main bar arrangement type classification Bent bar type. 6 Pedestrian Circulation--Stairs and. , S. I'm in the process of designing a elevated composite concrete and metal deck floor slab for a warehouse. Generally, a 4-inch slab will not need a rebar if the slab is used for a normal purpose. Build the wall full height, place concrete continuously in 4-foot lifts, and consolidate each lift. So, pathway slabs go under heavy loads continuously. Fiber length shall be 1 / 2 inch to 2. Most residential slabs contain. For slabs reinforced with rebar or wire mesh, this is considered fairly routine. The slab will have 1/4" vinyl applied to the top, and we were thinking of casting the slab without control joints to prevent curling at the joints. 5 Slabs on Grade - “the purpose of isolation joints in slabs on grade is to allow horizontal and vertical movement between the slab and adjoining structures such as walls, columns, footings, or specially loaded areas (machinery bases). 1) for con-c r ete cover over re i n f o rc e m e n t h a v e not been consistent. Divide your result by the spacing measurement: 180 in / 14 in = 12. Calculation Method For Find Out The Overlapping Length Of Beam, Column And Slab; Bar Bending Schedule For Slab And Estimation Of Steel Reinforcement In Slab; Calculation steps. The building code requires a minimum of No. 8. In either case, blocks should be used under the reinforcement to keep centered. You can use the concrete Rebar calculations to find the amount of. Wire mesh. 2: Repeat and continue to draw complete (closed) shape. 2. Narrow panels Fig. 3. It has a foot print of four tires about 10 inches by 10 inches time 4. 1 Storey Building: Typically, smaller diameter rebars like 10mm or 12mm might be suitable, depending on the specific design requirements. 1 can be used for these purposes. 1 of ACI 318-111 identifies a two-way slab as a slab system designed for flexure in more than one direction. If consolidation of plastic soils is determined to be a potential problem a suspended slab may be the only effective solution, in which. Advertise Here. A slab with this joint spacing may be reinforced with bars (ASTM A 615, A 616, A 617, or A 706) or WWF (ASTM A 185 or A 497). ˘ ˘ˇ Spacing (Rebar) A-7 4-1/2” 4000 psi with 28 day aging #6 rebar 12 in. If your concrete will be stamped, ask about the best ways to avoid interrupting the pattern. Thickness of concrete slab depends on loads and size of the slab. A good GPR survey and interpretation should give you the rebar spacing and pattern. R403. Place rebar in a grid pattern with a spacing between bars of approximately 12 inches. Max Bending Check. All floor elements were brought in as DECK elements. Metallic and non-metallic pipes and conduits. I maintain a concrete cover of 40 MM. Input all the dimensions in the input section of the above calculator. 4. Input the number of mesh in slab rebar. 3. 4. European, which is a carbon/steel/manganese alloy. ASCE, SECB COURSE CONTENT Slab on Grades Construction: Introduction Concrete slabs on grade are a very common type of concrete construction. The openings are square in shape and range in size from 2 ft to 5 ft. Finite elements 1st example 2nd example 3rd example. Prior to the placement of reinforcement for concrete floor slab construction, inspect and check forms to confirm that the dimensions and the location of the concrete members conform to the structural plans. Concrete slab reinforcement design and code checks can be performed based on the following codes: ACI 318-19. Matthew Stuart, P. 12% for HYSD bars and 0. Purpose. 561 kg/m. This new slab design does not account for second floor installations or installations in a ground floor with a basement beneath. reinforcing bars. Ch. Where the bar used is Grade 60 and the size specified in the table, the actual spacing in the wall shall not exceed a whole-number multiple of 12 inches (i. Secondly, the type and diameter of steel bar used for a concrete slab’s rebar depends on the design specifications’ load-bearing capacity. Go check out the park in Bellingham to see how Custom Concrete’s rebar and concrete installation is supporting that 400,000-pound piece of artwork! Rebar, or reinforcing bar, is a common feature of many concrete applications. I can't believe after being in this business for 12 years I've yet to pour a very long re-inforced concrete slab. Concrete slab-on-ground floors shall be designed and constructed in accordance with the provisions of this section or ACI 332. Total Volume of concrete in cubic yards. Often it is necessary to cut holes in concrete floor slabs. 5h ≤ 450mm (in areas of concentrated loads 3h ≤ 400mm) Where h is the thickness of. 530 m Therefore, gross area of building = 201. The minimum column size should not be less than 9 "x9". 3rd. The size of the rebar depends on the specific application, but typically #4, #5, #6, and #8 rebar are used. ˘ ˘ˇSpacing (Rebar) A-7 4-1/2” 4000 psi with 28 day aging #6 rebar 12 in. 3 Slabs-on-ground with turned-down footings. The slab is constructed on well compacted granular fill, crushed stone or marl. 34 and $7. 2130605 2 = second floor B = beam member 06 = 6/8- or 3/4-inch (1.