基础:J-3
3.1 工程名称:工程一
3.2 地基承载力特征值
3.2.1 计算公式:《建筑地基基础设计规范》(GB 50007-2002)
fa = fak + ηb * γ * (b - 3) + ηd * γm * (d - 0.5) (式 5.2.4)
地基承载力特征值 fak = 110kPa 基础宽度的地基承载力修正系数 ηb = 0
基础埋深的地基承载力修正系数 ηd = 1 基础底面以下土的重度 γ = 18kN/m
基础底面以上土的加权平均重度 γm = 18kN/m 基础底面宽度 b = 2.8m
基础埋置深度 d = 1.3m
当 b = 2.8m < 3m 时,按 b = 3m
3.2.2 fa = 110+0*18*(3-3)+1*18*(1.3-0.5) = 124.4kPa
修正后的地基承载力特征值 fa = 124.4kPa
3.3 基本资料
3.3.1 柱子高度 hc = 600mm (X 方向) 柱子宽度 bc = 400mm (Y 方向)
3.3.2 基础底面宽度 b = 2800mm (X 方向) 底面长度 l = 4200mm (Y 方向)
基础根部高度 H = 800mm 端部高度 h1 = 200mm
3.3.3 柱边基础截面面积
X 轴方向截面面积 Acb = h1 * b + (b + hc + 2*0.05) * (H - h1) / 2 = 1.61m Y 轴方向截面面积 Acl = h1 * l + (l + bc + 2*0.05) * (H - h1) / 2 = 2.25m
3.3.4 基础顶面坡度斜率 i = 1 / 1.8 坡度 αx = 29.7° αy = 18°
3.3.5 基础宽高比
基础柱边宽高比: (b - hc) / 2H = 1.4; (l - bc) / 2H = 2.4
3.3.6 混凝土强度等级为 C20 fc = 9.554N/mm ft = 1.101N/mm
3.3.7 钢筋强度设计值 fy = 300N/mm 纵筋合力点至近边距离 as = 50mm
3.3.8 荷载的综合分项系数 γz = 1.35 永久荷载的分项系数 γG = 1.2
3.3.9 基础底面积 A = l * b = 4.2*2.8 = 11.76m
顶部面积 At = (hc + 2*0.05) * (bc + 2*0.05) = (0.6+2*0.05)*(0.4+2*0.05)
= 0.35m
底部体积 Vjc1 = Ab * h1 = 11.76*0.2 = 2.352m
顶部体积 Vjc2 = [b * l + (b + hc + 2*0.05) * (l + bc + 2*0.05) + (hc
+ 2*0.05) * (bc + 2*0.05)] * (H - h1) / 6 = 2.856m
基础体积 Vjc = Vjc1 + Vjc2 = 2.352+2.856 = 5.208m
3.3.10 基础自重和基础上的土重
基础混凝土的容重 γc = 25kN/m 基础顶面以上土的容重 γs = 20kN/m
顶面上覆土厚度 ds = 1300mm
Gk = Vjc * γc + [A * (H + ds) - Vjc - bc * hc * ds] * γs = 513.7kN
基础自重和基础上的土重设计值 G = γG * Gk = 616.5kN 柱下扩展
3.3.11 基础上的竖向附加荷载标准值 Fk' = 0kN
3.4 控制内力
Nk ----------- 相应于荷载效应标准组合时,柱底轴向力值(kN );
Fk ----------- 相应于荷载效应标准组合时,作用于基础顶面的竖向力值(kN ); Fk = Nk + Fk'
Vkx 、Vky ---- 相应于荷载效应标准组合时,作用于基础顶面的剪力值(kN ); Mkx'、Mky' --- 相应于荷载效应标准组合时,作用于基础顶面的弯矩值(kN ·M ); Mkx 、Mky ---- 相应于荷载效应标准组合时,作用于基础底面的弯矩值(kN ·M ); Mkx = Mkx' - Vky * H、 Mky = Mky' + Vkx * H
F、Mx 、My --- 相应于荷载效应基本组合时,竖向力、弯矩设计值(kN 、kN ·M ); F = γz * Fk、 Mx = γz * Mkx、 My = γz * Mky
3.4.1 Nk = 37.5; Mkx'= -340.5; Mky'= 0; Vkx = -21.3; Vky = 0
Fk = 37.5; Mkx = -340.5; Mky = -17.1
F = 50.6; Mx = -459.7; My = -23
3.5 轴心荷载作用下
pk = (Fk + Gk) / A (式 5.2.2-1)
pk = (37.5+513.7)/11.76 = 46.9kPa ≤ fa = 124.4kPa,满足要求。
3.6 偏心荷载作用下
pkmax = (Fk + Gk) / A + Mk / W (式 5.2.2-2)
pkmin = (Fk + Gk) / A - Mk / W (式 5.2.2-3)
双向偏心荷载作用下
pkmax = (Fk + Gk) / A + Mkx / Wx + Mky / Wy
pkmin = (Fk + Gk) / A - Mkx / Wx - Mky / Wy
基础底面抵抗矩 Wx = b * l * l / 6 = 2.8*4.2*4.2/6 = 8.232m
基础底面抵抗矩 Wy = l * b * b / 6 = 4.2*2.8*2.8/6 = 5.488m
Mkx = 340.5kN·m Mky = 17.1kN·m
pkmax = (37.5+513.7)/11.76+340.5/8.232+17.1/5.488
= 91.3kPa ≤ 1.2fa = 149.3kPa,满足要求。
pkmin = (37.5+513.7)/11.76-340.5/8.232-17.1/5.488 = 2.4kPa ≥ 0,满足要求。 偏心矩 ex = Mky / (Fk + Gk) = 17.1/(37.5+513.7) = 0.031m
pkmaxX = (37.5+513.7)/11.76+17.1/5.488
= 50.0kPa ≤ 1.2fa = 149.3kPa,满足要求。
pkminX = (37.5+513.7)/11.76-17.1/5.488 = 43.8kPa
偏心矩 ey = Mkx / (Fk + Gk) = 340.5/(37.5+513.7) = 0.618m
pkmaxY = (37.5+513.7)/11.76+340.5/8.232
= 88.2kPa ≤ 1.2fa = 149.3kPa,满足要求。
pkminY = (37.5+513.7)/11.76-340.5/8.232 = 5.5kPa
3.7 冲切验算
Fl ≤ 0.7 * βhp * ft * am * Ho (式 8.2.7-1)
am = (at + ab) / 2 (式 8.2.7-2)
Fl = pj * Al (式 8.2.7-3)
3.7.1 基底净反力 pj
pmax = γz * 91.3 = 123.3kPa
pj = pmax - G / A = 123.3-616.5/11.76 = 70.9kPa
3.7.2 X 方向(b 方向)
因 b > hc + 2Ho 且 l - bc > b - hc 有:
Alx = 0.5 * (b - hc + 2bc + 2Ho) * [(b - hc) / 2 - Ho]
= 0.5*(2.8-0.6+2*0.4+2*0.75)*[(1-12)-2-0.75] = 0.79m
ab = Min{bc + 2Ho,l} = Min{0.4+2*0.75,4.2} = 1.900m
amx = (bc + ab) / 2 = (0.4+1.9)/2 = 1.150m
Flx = pj * Alx = 70.9*0.79 = 55.8kN
0.7 * βhp * ft * amx * Ho = 0.7*1*1101*1.15*0.75 = 664.9kN
≥ Flx = 55.8kN,满足要求。
3.7.3 Y 方向(l 方向)
因 l > bc + 2Ho、b > hc + 2Ho 且 b - hc ≤ l - bc 有:
Aly = 0.5(b + hc + 2Ho) * (b - hc - 2Ho) / 2 + b * (l - bc - b + hc) / 2 = 0.5*(2.8+0.6+2*0.75)*(2.8-0.6-2*0.75)/2+2.8*(4.2-0.4-2.8+0.6)/2 = 3.10m
ab = Min{hc + 2Ho,b} = Min{0.6+2*0.75,2.8} = 2.100m
amy = (hc + ab) / 2 = (0.6+2.1)/2 = 1.350m
Fly = pj * Aly = 70.9*3.1 = 219.6kN
0.7 * βhp * ft * amy * Ho = 0.7*1*1101*1.35*0.75 = 780.5kN
≥ Fly = 219.6kN,满足要求。
3.8 剪切验算
V ≤ 0.7 * βh * ft * bo * Ho (混凝土规范式 7.5.3-1)
3.8.1 X 方向(b 方向)
计算宽度 Lo = {1 - 0.5 * [1 - (bc + 2*50) / l] * (Ho - h1) / Ho} * l = 2843mm Vx = pj * Ax = pj * (b - hc) * 2l
Vx = 70.9*(2.8-0.6)*4.2/2 = 327.6kN
0.7 * βh * ft * Lo * Ho = 0.7*1*1101*2.843*0.75
= 1643.9kN ≥ Vx = 327.6kN,满足要求。
3.8.2 Y 方向(l 方向)
计算宽度 Bo = {1 - 0.5 * [1 - (hc + 2*50) / b] * (Ho - h1) / Ho} * b = 2030mm Vy = pj * Ay = pj * (l - bc) * 2b
Vy = 70.9*(4.2-0.4)*2.8/2 = 377.2kN
0.7 * βh * ft * Bo * Ho = 0.7*1*1101*2.03*0.75
= 1173.7kN ≥ Vy = 377.2kN,满足要求。
3.9 抗弯计算
3.9.1 弯矩计算
MⅠ按地基规范式 8.2.7-4 计算:
MⅠ = a1 ^ 2 * [(2l + a') * (pmax + p - 2G / A) + (pmax - p) * l] / 12 X 方向(b 方向)柱边(绕 Y 轴):
MⅠ = (b - hc) ^ 2 * [(2l + bc) * (pmaxX + pX - 2G / A)
+ (pmaxX - pX) * l] / 48
pX = pminX + (pmaxX - pminX) * (b + hc) / 2b
= 59.1+(67.5-59.1)*(2.8+0.6)/2.8/2 = 64.2kPa
MⅠ = (2.8-0.6)^2*[(2*4.2+0.4)*(67.5+64.2-2*616.5/11.76)+(67.5-64.2)*4.2]/48 = 25.2kN·m
Y 方向(l 方向)柱边(绕 X 轴):
MⅡ = (l - bc) ^ 2 * [(2b + hc) * (pmaxY + pY - 2G / A)
+ (pmaxY - pY) * b] / 48
pY = pminY + (pmaxY - pminY) * (l + bc) / 2l
= 7.4+(119.1-7.4)*(4.2+0.4)/4.2/2 = 68.6kPa
MⅡ = (4.2-0.4)^2*[(2*2.8+0.6)*(119.1+68.6-2*616.5/11.76)+(119.1-68.6)*2.8]/48 = 197.1kN·m
3.9.2 配筋计算
MⅠmax = 25.2kN·m MⅡmax = 197.1kN·m
①号筋 AsⅠ = 114mm (x = 7mm) 相对受压区高度 ξ = 0.009
as = 62mm 配筋率 ρ = 0.01%
ρmin = 0.15% AsⅠmin = 3375mm 33Φ12@125 (As = 3732)
②号筋 AsⅡ = 899mm (x = 37mm) 相对受压区高度 ξ = 0.049
as = 50mm 配筋率 ρ = 0.06%
ρmin = 0.15% AsⅡmin = 2415mm 22Φ12@125 (As = 2488)
3.10 柱下局部受压承载力计算
Fl ≤ ω * βl * fcc * Al (混凝土规范式 A.5.1-1)
局部荷载设计值 Fl = 50.6kN
混凝土局部受压面积 Al = bc * hc = 240000mm
基础在柱下局部受压时的计算底面积按下列公式计算:
Ab = (bx + 2c) * (by + 2c)
c = Min{Cx, Cy, bx, by} = Min{50,50,600,400} = 50mm
Ab = (600+2*50)*(400+2*50) = 350000mm
混凝土局部受压时的强度提高系数 βl = (Ab / Al) ^ 0.5 = (0.35/0.24)^0.5 = 1.208
ω * βl * fcc * Al = 1.0*1.208*0.85*9554*0.24 = 2353.7kN
≥ Fl = 50.6kN,满足要求。
__________________________________________________________________________________
【MorGain 结构快速设计程序 V2004.15.1162.0】 Date:2011-03-18 15:20:35
______________________________http://www.MorGain.com______________________________
基础:J-3
3.1 工程名称:工程一
3.2 地基承载力特征值
3.2.1 计算公式:《建筑地基基础设计规范》(GB 50007-2002)
fa = fak + ηb * γ * (b - 3) + ηd * γm * (d - 0.5) (式 5.2.4)
地基承载力特征值 fak = 110kPa 基础宽度的地基承载力修正系数 ηb = 0
基础埋深的地基承载力修正系数 ηd = 1 基础底面以下土的重度 γ = 18kN/m
基础底面以上土的加权平均重度 γm = 18kN/m 基础底面宽度 b = 2.8m
基础埋置深度 d = 1.3m
当 b = 2.8m < 3m 时,按 b = 3m
3.2.2 fa = 110+0*18*(3-3)+1*18*(1.3-0.5) = 124.4kPa
修正后的地基承载力特征值 fa = 124.4kPa
3.3 基本资料
3.3.1 柱子高度 hc = 600mm (X 方向) 柱子宽度 bc = 400mm (Y 方向)
3.3.2 基础底面宽度 b = 2800mm (X 方向) 底面长度 l = 4200mm (Y 方向)
基础根部高度 H = 800mm 端部高度 h1 = 200mm
3.3.3 柱边基础截面面积
X 轴方向截面面积 Acb = h1 * b + (b + hc + 2*0.05) * (H - h1) / 2 = 1.61m Y 轴方向截面面积 Acl = h1 * l + (l + bc + 2*0.05) * (H - h1) / 2 = 2.25m
3.3.4 基础顶面坡度斜率 i = 1 / 1.8 坡度 αx = 29.7° αy = 18°
3.3.5 基础宽高比
基础柱边宽高比: (b - hc) / 2H = 1.4; (l - bc) / 2H = 2.4
3.3.6 混凝土强度等级为 C20 fc = 9.554N/mm ft = 1.101N/mm
3.3.7 钢筋强度设计值 fy = 300N/mm 纵筋合力点至近边距离 as = 50mm
3.3.8 荷载的综合分项系数 γz = 1.35 永久荷载的分项系数 γG = 1.2
3.3.9 基础底面积 A = l * b = 4.2*2.8 = 11.76m
顶部面积 At = (hc + 2*0.05) * (bc + 2*0.05) = (0.6+2*0.05)*(0.4+2*0.05)
= 0.35m
底部体积 Vjc1 = Ab * h1 = 11.76*0.2 = 2.352m
顶部体积 Vjc2 = [b * l + (b + hc + 2*0.05) * (l + bc + 2*0.05) + (hc
+ 2*0.05) * (bc + 2*0.05)] * (H - h1) / 6 = 2.856m
基础体积 Vjc = Vjc1 + Vjc2 = 2.352+2.856 = 5.208m
3.3.10 基础自重和基础上的土重
基础混凝土的容重 γc = 25kN/m 基础顶面以上土的容重 γs = 20kN/m
顶面上覆土厚度 ds = 1300mm
Gk = Vjc * γc + [A * (H + ds) - Vjc - bc * hc * ds] * γs = 513.7kN
基础自重和基础上的土重设计值 G = γG * Gk = 616.5kN 柱下扩展
3.3.11 基础上的竖向附加荷载标准值 Fk' = 0kN
3.4 控制内力
Nk ----------- 相应于荷载效应标准组合时,柱底轴向力值(kN );
Fk ----------- 相应于荷载效应标准组合时,作用于基础顶面的竖向力值(kN ); Fk = Nk + Fk'
Vkx 、Vky ---- 相应于荷载效应标准组合时,作用于基础顶面的剪力值(kN ); Mkx'、Mky' --- 相应于荷载效应标准组合时,作用于基础顶面的弯矩值(kN ·M ); Mkx 、Mky ---- 相应于荷载效应标准组合时,作用于基础底面的弯矩值(kN ·M ); Mkx = Mkx' - Vky * H、 Mky = Mky' + Vkx * H
F、Mx 、My --- 相应于荷载效应基本组合时,竖向力、弯矩设计值(kN 、kN ·M ); F = γz * Fk、 Mx = γz * Mkx、 My = γz * Mky
3.4.1 Nk = 37.5; Mkx'= -340.5; Mky'= 0; Vkx = -21.3; Vky = 0
Fk = 37.5; Mkx = -340.5; Mky = -17.1
F = 50.6; Mx = -459.7; My = -23
3.5 轴心荷载作用下
pk = (Fk + Gk) / A (式 5.2.2-1)
pk = (37.5+513.7)/11.76 = 46.9kPa ≤ fa = 124.4kPa,满足要求。
3.6 偏心荷载作用下
pkmax = (Fk + Gk) / A + Mk / W (式 5.2.2-2)
pkmin = (Fk + Gk) / A - Mk / W (式 5.2.2-3)
双向偏心荷载作用下
pkmax = (Fk + Gk) / A + Mkx / Wx + Mky / Wy
pkmin = (Fk + Gk) / A - Mkx / Wx - Mky / Wy
基础底面抵抗矩 Wx = b * l * l / 6 = 2.8*4.2*4.2/6 = 8.232m
基础底面抵抗矩 Wy = l * b * b / 6 = 4.2*2.8*2.8/6 = 5.488m
Mkx = 340.5kN·m Mky = 17.1kN·m
pkmax = (37.5+513.7)/11.76+340.5/8.232+17.1/5.488
= 91.3kPa ≤ 1.2fa = 149.3kPa,满足要求。
pkmin = (37.5+513.7)/11.76-340.5/8.232-17.1/5.488 = 2.4kPa ≥ 0,满足要求。 偏心矩 ex = Mky / (Fk + Gk) = 17.1/(37.5+513.7) = 0.031m
pkmaxX = (37.5+513.7)/11.76+17.1/5.488
= 50.0kPa ≤ 1.2fa = 149.3kPa,满足要求。
pkminX = (37.5+513.7)/11.76-17.1/5.488 = 43.8kPa
偏心矩 ey = Mkx / (Fk + Gk) = 340.5/(37.5+513.7) = 0.618m
pkmaxY = (37.5+513.7)/11.76+340.5/8.232
= 88.2kPa ≤ 1.2fa = 149.3kPa,满足要求。
pkminY = (37.5+513.7)/11.76-340.5/8.232 = 5.5kPa
3.7 冲切验算
Fl ≤ 0.7 * βhp * ft * am * Ho (式 8.2.7-1)
am = (at + ab) / 2 (式 8.2.7-2)
Fl = pj * Al (式 8.2.7-3)
3.7.1 基底净反力 pj
pmax = γz * 91.3 = 123.3kPa
pj = pmax - G / A = 123.3-616.5/11.76 = 70.9kPa
3.7.2 X 方向(b 方向)
因 b > hc + 2Ho 且 l - bc > b - hc 有:
Alx = 0.5 * (b - hc + 2bc + 2Ho) * [(b - hc) / 2 - Ho]
= 0.5*(2.8-0.6+2*0.4+2*0.75)*[(1-12)-2-0.75] = 0.79m
ab = Min{bc + 2Ho,l} = Min{0.4+2*0.75,4.2} = 1.900m
amx = (bc + ab) / 2 = (0.4+1.9)/2 = 1.150m
Flx = pj * Alx = 70.9*0.79 = 55.8kN
0.7 * βhp * ft * amx * Ho = 0.7*1*1101*1.15*0.75 = 664.9kN
≥ Flx = 55.8kN,满足要求。
3.7.3 Y 方向(l 方向)
因 l > bc + 2Ho、b > hc + 2Ho 且 b - hc ≤ l - bc 有:
Aly = 0.5(b + hc + 2Ho) * (b - hc - 2Ho) / 2 + b * (l - bc - b + hc) / 2 = 0.5*(2.8+0.6+2*0.75)*(2.8-0.6-2*0.75)/2+2.8*(4.2-0.4-2.8+0.6)/2 = 3.10m
ab = Min{hc + 2Ho,b} = Min{0.6+2*0.75,2.8} = 2.100m
amy = (hc + ab) / 2 = (0.6+2.1)/2 = 1.350m
Fly = pj * Aly = 70.9*3.1 = 219.6kN
0.7 * βhp * ft * amy * Ho = 0.7*1*1101*1.35*0.75 = 780.5kN
≥ Fly = 219.6kN,满足要求。
3.8 剪切验算
V ≤ 0.7 * βh * ft * bo * Ho (混凝土规范式 7.5.3-1)
3.8.1 X 方向(b 方向)
计算宽度 Lo = {1 - 0.5 * [1 - (bc + 2*50) / l] * (Ho - h1) / Ho} * l = 2843mm Vx = pj * Ax = pj * (b - hc) * 2l
Vx = 70.9*(2.8-0.6)*4.2/2 = 327.6kN
0.7 * βh * ft * Lo * Ho = 0.7*1*1101*2.843*0.75
= 1643.9kN ≥ Vx = 327.6kN,满足要求。
3.8.2 Y 方向(l 方向)
计算宽度 Bo = {1 - 0.5 * [1 - (hc + 2*50) / b] * (Ho - h1) / Ho} * b = 2030mm Vy = pj * Ay = pj * (l - bc) * 2b
Vy = 70.9*(4.2-0.4)*2.8/2 = 377.2kN
0.7 * βh * ft * Bo * Ho = 0.7*1*1101*2.03*0.75
= 1173.7kN ≥ Vy = 377.2kN,满足要求。
3.9 抗弯计算
3.9.1 弯矩计算
MⅠ按地基规范式 8.2.7-4 计算:
MⅠ = a1 ^ 2 * [(2l + a') * (pmax + p - 2G / A) + (pmax - p) * l] / 12 X 方向(b 方向)柱边(绕 Y 轴):
MⅠ = (b - hc) ^ 2 * [(2l + bc) * (pmaxX + pX - 2G / A)
+ (pmaxX - pX) * l] / 48
pX = pminX + (pmaxX - pminX) * (b + hc) / 2b
= 59.1+(67.5-59.1)*(2.8+0.6)/2.8/2 = 64.2kPa
MⅠ = (2.8-0.6)^2*[(2*4.2+0.4)*(67.5+64.2-2*616.5/11.76)+(67.5-64.2)*4.2]/48 = 25.2kN·m
Y 方向(l 方向)柱边(绕 X 轴):
MⅡ = (l - bc) ^ 2 * [(2b + hc) * (pmaxY + pY - 2G / A)
+ (pmaxY - pY) * b] / 48
pY = pminY + (pmaxY - pminY) * (l + bc) / 2l
= 7.4+(119.1-7.4)*(4.2+0.4)/4.2/2 = 68.6kPa
MⅡ = (4.2-0.4)^2*[(2*2.8+0.6)*(119.1+68.6-2*616.5/11.76)+(119.1-68.6)*2.8]/48 = 197.1kN·m
3.9.2 配筋计算
MⅠmax = 25.2kN·m MⅡmax = 197.1kN·m
①号筋 AsⅠ = 114mm (x = 7mm) 相对受压区高度 ξ = 0.009
as = 62mm 配筋率 ρ = 0.01%
ρmin = 0.15% AsⅠmin = 3375mm 33Φ12@125 (As = 3732)
②号筋 AsⅡ = 899mm (x = 37mm) 相对受压区高度 ξ = 0.049
as = 50mm 配筋率 ρ = 0.06%
ρmin = 0.15% AsⅡmin = 2415mm 22Φ12@125 (As = 2488)
3.10 柱下局部受压承载力计算
Fl ≤ ω * βl * fcc * Al (混凝土规范式 A.5.1-1)
局部荷载设计值 Fl = 50.6kN
混凝土局部受压面积 Al = bc * hc = 240000mm
基础在柱下局部受压时的计算底面积按下列公式计算:
Ab = (bx + 2c) * (by + 2c)
c = Min{Cx, Cy, bx, by} = Min{50,50,600,400} = 50mm
Ab = (600+2*50)*(400+2*50) = 350000mm
混凝土局部受压时的强度提高系数 βl = (Ab / Al) ^ 0.5 = (0.35/0.24)^0.5 = 1.208
ω * βl * fcc * Al = 1.0*1.208*0.85*9554*0.24 = 2353.7kN
≥ Fl = 50.6kN,满足要求。
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【MorGain 结构快速设计程序 V2004.15.1162.0】 Date:2011-03-18 15:20:35
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