根据下图所示水准路线中的数据，计算P、Q点的高程。 (1)计算高差闭合差：(2)若高差闭合差fh不超过fh允即|fh|<|fh允|,(3)计算改正后的高差的高程
答：(1)△h = HBM2 - HBM1 = 157.732 – 163.751 = -6.019 m∑h = -3.001 – 4.740 + 1.719 = = - 6.022m
fh = ∑h - △h = -6.022 – (-6.019) = -0.003m = -3mm
(2)分配闭合差，计算改正数
∑L = 1.4 + 6.3 + 3.5 = 11.2 km
v1 = - (L1/∑L) * fh = 0mm
v2 = - (L2/∑L) * fh = 2mm
v3 =- (L3/∑L) * fh =1mm
∑v=-fh(检核)
(3)HP = HBM1 + h1 + v1 = 163.751 – 3.001 + 0 = 160.750m
HQ = HP + h2 + v2 = 160.750 – 4.740 + (0.002) = 160.750 – 4.738 = 156.012m
或HQ = HBM2+ (h3 + v3) = 157.732 – 1.719 –0.001 = 160.750 – 4.738 = 156.012m
HBM2 = HQ +(h3 + v3)=157.732m(检核)
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