### 2.43 Campbell (1984) & K.W. Campbell (1988) reported in Joyner and Boore (1988)

• Ground-motion model is:
where y is in g, a = -2.817, b = 0.702, d = -1.20, h1 = 0.0921, h2 = 0.584, e1 = 0.32, e2 = 0.52, e3 = 0.41, e4 = -0.85, e5 = -1.14, e6 = 0.87, e7 = 0.068 and σ = 0.30.8
• Uses two site categories:
K3 = 1
Soils 10m deep.
K3 = 0
Other.
• Uses three embedment categories:
K4 = 1, K5 = 0
Basements of buildings 39 storeys.
K5 = 1, K4 = 0
Basements of buildings 10 storeys.
K4 = 0, K5 = 0
Other.
• Selects data using these criteria:
1.
Largest horizontal component of peak acceleration was 0.02g [0.2ms2].
2.
Accelerograph triggered early enough to record strongest phase of shaking.
3.
Magnitude of earthquake was 5.0.
4.
Closest distance to seismogenic rupture was < 30 or < 50km, depending on whether magnitude of earthquake was < 6.25 or > 6.25.
5.
Shallowest extent of seismogenic rupture was 25km.
6.
Recording site located on unconsolidated deposits.
• Excludes records from abutments or toes of dams.
• Derives two equations: unconstrained (coefficients given above) and constrained which includes a anelastic decay term kr which allows equation to be used for predictions outside near-source zone (assumes k = -0.0059 for regression, a value appropriate for region of interest should be chosen).
• Uses two source mechanism categories:
K1 = 0
Strike-slip.
K1 = 1
Reverse.
• Uses two directivity categories:
K2 = 1
Rupture toward site.
K2 = 0
Other.

8Thenhaus et al. (1989) summarise a model by K.W. Campbell (1984, 1987) where: a = -3.303, b = 0.85, d = -1.25, h1 = 0.0872, h2 = 0.678, e1 = 0.34 and includes an anelastic term -0.0059r (σ is not reported), which they use for western Saudi Arabia.